XOMA CORP /DE/
10-K, 1998-03-19
PHARMACEUTICAL PREPARATIONS
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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10-K

[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934

                                       OR

[  ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934 

For the fiscal year ended
December 31, 1997                                Commission File No. 0-14710

                                XOMA CORPORATION
             (Exact name of registrant as specified in its charter)

         DELAWARE                                    94-2756657
 (State of Incorporation)               (I.R.S. Employer Identification No.)
   2910 Seventh Street,
   Berkeley, California                                94710
  (Address of principal                              (Zip Code)
    executive offices)

               Registrant's telephone number, including area code:
                                 (510) 644-1170

           Securities registered pursuant to Section 12(b) of the Act:
                                      None

           Securities registered pursuant to Section 12(g) of the Act:
                         Common Stock, $.0005 par value
                         Preferred Stock Purchase Rights

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes X No ______

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

     The aggregate market value of voting stock held by nonaffiliates of the
registrant, as of February 28, 1998: $200,005,539.

     Number of shares of Common Stock outstanding as of February 28, 1998:
40,524,221.

                       DOCUMENTS INCORPORATED BY REFERENCE

     Portions of the Company's Proxy Statement for the Company's 1998 Annual
Meeting of Stockholders are incorporated by reference into Part III of this
Report.


<PAGE>

                                     PART I


Item 1.        Business

     General

     XOMA Corporation ("XOMA" or the "Company") is a biopharmaceutical company
developing products to treat infections, infectious complications of traumatic
injury and surgery, and immunologic and inflammatory disorders. The Company's
current product development programs include:

     Neuprex(TM) (rBPI21), a modified recombinantly-derived fragment of human
bactericidal/permeability-increasing protein ("BPI") and XOMA's lead BPI-derived
product, which is currently in Phase III efficacy clinical trials in two
indications and in earlier-stage clinical trials in three additional
indications.

     I-PREX(TM), a proprietary topical formulation of rBPI21 for the treatment
of ophthalmic disorders, which is undergoing preclinical testing as a treatment
for corneal injuries, including ulcerations and transplants.

     Mycoprex(TM), a fungicidal peptide compound derived from BPI that is
currently in preclinical product development.

     hu1124 (anti-CD11a), a humanized monoclonal antibody product being
developed in collaboration with Genentech, Inc. ("Genentech"), which originally
discovered the antibody and characterized it as anti-CD11a. The hu1124 product
is in Phase II clinical trials for psoriasis. Other indications are under
review.

     In April 1997, XOMA and Pfizer Inc. ("Pfizer") decided to discontinue the
U.S. clinical trial of the Company's E5(R) monoclonal antibody product as a
treatment for gram-negative sepsis. In June 1997, the Company announced that
Pfizer had decided to end its marketing arrangement for E5(R).

     Product Areas

     The following describes XOMA's more significant therapeutic product
development and clinical activities:

The BPI Product Platform

     The Company's current programs are primarily focused on developing novel
therapeutic products from bactericidal/permeability-increasing protein ("BPI").
BPI is a naturally-occurring human host-defense protein found in white blood
cells (neutrophils). BPI kills certain bacteria. It also binds to and
neutralizes endotoxins, molecular components of the cell walls of gram-negative
bacteria that can trigger severe complications in infected patients.
Furthermore, BPI inhibits angiogenesis (growth of new blood vessels) by binding
to and neutralizing heparin, a natural protein involved in blood vessel
formation. Angiogenesis is an essential component of inflammation and solid
tumor growth.

     BPI was discovered in 1978 by Peter Elsbach, M.D., Professor of Medicine,
and Jerrold Weiss, Ph.D., Professor of Microbiology, both at New York University
School of Medicine. XOMA has collaborated with NYU since 1991 to extend and
apply BPI-related research to the commercial development of pharmaceutical
products. Since March 1993, the U.S. Patent and Trademark Office ("Patent
Office") has issued four patents and a Notice of Allowance relating to BPI to
NYU, and the Company is the exclusive licensee of these 



                                       2
<PAGE>

patents and the Notice of Allowance. See "Patents and Trade Secrets". XOMA has
an agreement with New York University ("NYU") relating to its rBPI products. See
"Research and License Agreements".

     XOMA has adopted the BPI molecule as a platform for developing multiple
pharmaceutical products. In 1991 XOMA scientists developed a modified
recombinant fragment of the BPI molecule, called rBPI21, which is potent and
stable and can be manufactured at commercially viable yields. This modified
fragment is the basis for the Company's Neuprex(TM) and I-PREX(TM) products. In
1994 XOMA scientists discovered three functional domains in the BPI molecule
with pharmacologically-desirable activities. Based on this discovery, XOMA is
developing peptides from these domains into additional therapeutic products,
including the Mycoprex(TM) antifungal peptide product.

Neuprex(TM)

     In December 1992, XOMA submitted an investigational new drug application
("IND") to the U.S. Food and Drug Administration ("FDA") to begin Phase I human
testing of Neuprex(TM). In March 1993, the Company began Phase I human safety
and pharmocokinetic testing under the IND. Beginning in 1995, the Company
initiated five clinical efficacy studies evaluating Neuprex(TM) as a treatment
for primary infections and major complications of infectious diseases, traumatic
injury and surgery. These indications are:

     Severe pediatric meningococcemia: a deadly bacterial infection that usually
afflicts children. In August 1996, FDA's Center for Biologics Evaluation and
Research ("CBER") granted XOMA a Subpart E designation for Neuprex(TM) for the
treatment of severe pediatric meningococcemia following favorable results in an
open label Phase I/ II pilot study. This designation is intended to expedite the
development of treatments for life-threatening illnesses. The Company
subsequently began a Phase III pivotal trial for the indication in October 1996
in the United States and Canada. In the first quarter of 1997, XOMA added a
trial site in the United Kingdom to increase patient accrual. The company
enrolled additional U.K. sites in late 1997 and early 1998.

     Hemorrhage due to trauma: accidents or injuries that cause acute blood loss
may trigger serious complications in up to 40% of patients who survive the
initial trauma and surgery. These patients may be infected by bacteria and their
endotoxins translocated from the gastrointestinal tract into the bloodstream. A
placebo-controlled, double-blinded Phase II study in 401 patients began in June
1995 and was completed in October 1996. A follow-on single-blinded Phase II
pharmacokinetics study explored alternative dosing regimens in 169 patients.
Based on data from the Phase II studies, XOMA initiated in the fourth quarter of
1997 a Phase III pivotal trial, designed to enroll 1650 patients in 40 centers,
testing Neuprex(TM) to prevent serious pulmonary complications in trauma
patients.

     Partial hepatectomy: surgical removal of part of the liver, usually to
remove an isolated tumor temporarily impairs liver function. Since the liver
normally clears bacteria and their endotoxins, these patients are at risk for
infectious complications. The double-blinded, placebo-controlled Phase II study
in 35 patients began in mid-1995 and was concluded at the end of 1997. Review
and analysis of results is in progress.

     Severe intra-abdominal infections: in 1996, the Company began a Phase I/II
open-label dose-ranging study testing Neuprex(TM) with conventional antibiotics
to treat patients with serious abdominal infections that required surgery.

     Cystic fibrosis (CF): in the third quarter of 1997, XOMA initiated a
program to test Neuprex(TM) in CF patients whose genetic disorder predisposes
them to recurring bacterial lung infections (exacerbations). Over repeated
antibiotic treatments, the infecting bacteria often become resistant to
antibiotic treatment. A natural history study in the second half of 1997 tested
rBPI21, alone and in combina-



                                       3
<PAGE>

tion with antibiotics, against bacterial cultures collected from CF patients. A
Phase I safety and pharmacokinetics study began in the fourth quarter of 1997.

     There can be no assurance that any of the continuing trials will yield data
that will result in licensure of Neuprex(TM) in the U.S.

I-PREX(TM)

     XOMA has developed a proprietary topical formulation of rBPI21 for the
treatment of ophthalmic infections. Although standard antibiotics fight
bacterial infections, they do not inhibit the growth of new blood vessels in the
cornea that may be associated with these infections. This neovascularization can
lead to scarring and permanently impaired vision. In preclinical testing, the
I-PREX(TM) product has shown both anti-ineffective and anti-angiogenic
(inhibition of blood vessel growth) properties in the treatment of corneal
injury and associated infection. The use of I-PREX(TM) to treat corneal
injuries, including ulcers and other corneal diseases, could eliminate the need
for current anti-inflammatory therapies, such as corticosteroids, which have
undesirable side effects.

Mycoprex(TM)

     XOMA scientists discovered that certain peptide sequences derived from BPI
display potent fungicidal activity. Further research demonstrated that many of
these compounds not only kill strains of Candida, the most common fungi to cause
systemic illness, but also show activity against other strains of fungi,
including those resistant to the currently available drugs. Based on these
findings, the Company is conducting a program to develop compounds with a broad
spectrum of fungicidal activity and a better safety profile than
currently-available fungicidals.

LBP Assay

     In the first quarter of 1997, the Company granted to BioSite Diagnostics
Incorporated of San Diego, California an exclusive U.S. license to make, use and
sell certain non-automated, point-of-care diagnostic and prognostic products for
measuring Lipopolysaccharide Binding Protein ("LBP") to detect bacterial
endotoxin exposure in patients with endotoxemia or sepsis. A non-exclusive
license was granted to SRL, Inc., a Japanese company, to make, use and sell
certain automated diagnostic and prognostic products for centralized laboratory
use in Japan.

hu1124 (anti-CD11a) Monoclonal Antibody Product

     In April 1996, XOMA and Genentech entered into an agreement to co-develop
Genentech's anti-CD11a humanized monoclonal antibody product (hu1124). In late
1996, the Company started a Phase I trial in moderate to severe psoriasis
patients. In the second quarter of 1997, in response to findings that hu1124 was
active at smaller doses, XOMA started additional Phase I studies at lower doses.
XOMA announced a Phase II efficacy study in Canadian psoriasis patients in
February 1998. Other indications are under review by XOMA and Genentech.

Additional Product Areas

     XOMA continues to seek opportunities to realize value from products and
technologies outside its core research efforts, including immunoconjugates,
immunofusions, mammalian and microbial cell expression technologies,
osteoinductive proteins for bone repair, and non-cariogenic proteins for
low-calorie flavor enhancement. Various licenses and sublicenses have been
entered into in these areas. Discussions are ongoing with other entities that
have expressed interest in these products and technologies. No assurance can be
given that any agreement or agreements will be reached as a result of the
ongoing discussions.



                                       4
<PAGE>

     In 1996, XOMA received a $2.2 million payment related to the sale of its
T-cell receptor ("TCR") technology to Connective Therapeutics, Inc., now called
Connetics Corporation ("Connetics"). Connetics is using the technology in its
TCR vaccines in development for treatment of multiple sclerosis (MS) and
rheumatoid arthritis. XOMA is entitled to royalties on future sales of these
products. In December 1997, Connetics successfully completed a Phase I/II study
of their MS TCR vaccine.

     In 1996, XOMA also received a $3.0 million payment for an exclusive license
to Genentech, including a sublicense to IDEC Pharmaceuticals Corporation
("IDEC"), to intellectual property covering the use of chimeric IgG1 antibodies
specific to the CD20 antigen on the surface of human B-cells. XOMA was entitled
to royalties on the sale of products employing the anti-CD20 technology that are
sold in the United States and in other countries where XOMA held relevant
patents. In December 1997, XOMA assigned these anti-CD20 antibody patents and
royalty rights to Pharmaceutical Partners, LLC for $17.0 million.

     XOMA has granted licenses to a number of biotechnology and pharmaceutical
companies for use of patented and proprietary technologies relating to a
bacterial expression system used to manufacture recombinant pharmaceutical
products. Licensees include: Affymax Research Institute, Cantab Pharmaceuticals
Research Ltd, Eli Lilly and Company, Enzon, Inc., the Hoechst Group, ICOS
Corporation, Invitrogen Corporation, Pasteur Merieux Serums & Vaccins, and The
Pharmacia & Upjohn Group.

     Genimune(TM) is XOMA's humanized immunofusion product that targets T
lymphocytes (white blood cells that attack foreign cells) in autoimmune disease
therapy. For several years, the Company developed and evaluated several
proprietary variants of genetically-engineered proteins and targeted
immunofusions ("TIF"). In mid-1993 the Company selected a lead immunofusion
compound designated Genimune(TM). In December 1993, XOMA entered into
cross-license agreements with Research Development Foundation concerning
recombinant DNA-derived gelonin ("r-gelonin"), a plant-derived cytotoxic enzyme
used as a TIF component. In the fourth quarter of 1994, XOMA terminated further
internal development of Genimune(TM) and is attempting to outlicense the
product, but no assurance can be given that it will successfully do so.

     Thaumatin, a flavor-enhancing protein developed by XOMA, was classified as
generally recognized as safe ("GRAS") by the Flavor and Extract Manufacturer's
Association ("FEMA"). GRAS designation permits the use of this ingredient as a
flavor enhancer in food without additional regulatory approval. Thaumatin is the
first flavoring ingredient produced through biotechnology to be granted GRAS
status. The Company is seeking to outlicense this technology, but no assurance
can be given that it will successfully do so.

     Manufacturing

     XOMA is currently producing its Neuprex(TM) and hu1124 products for
clinical trial and other testing needs at its Berkeley manufacturing facility,
pursuant to a drug manufacturing license obtained from the State of California.

     The Company's manufacturing capability is based on recombinant DNA
technology, with production of therapeutic proteins from either mammalian or
microbial cells. XOMA has fermentation capacity for up to 5500 liters with
associated isolation and purification systems in place. The Company does its own
formulation for final sterile filling and finishing and has the capacity to do
its own small-scale filling.

     Development and Marketing Arrangements

     The Company has developed a strategy of entering into arrangements with
established pharmaceutical company partners in order to facilitate and finance
the development and marketing of its products. Assuming timely regulatory
approval, which cannot be assured, the successful commercialization of XOMA's
products will be dependent to a large extent upon the marketing capabilities of
any pharmaceutical partners.



                                       5
<PAGE>

Neuprex(TM)

     The Company is seeking one or more strategic alliances with respect to its
Neuprex(TM) product. Discussions have taken place with several entities
regarding such a product alliance. The Company cannot predict whether or when
any such alliance(s) will be consummated.

hu1124 (antiCD11a)

     In April 1996, XOMA and Genentech entered into an agreement whereby XOMA
agreed to co-develop Genentech's humanized monoclonal antibody product,
originally called anti-CD11a. Under the terms of the agreement Genentech
purchased 1.5 million shares of XOMA common stock at $5.90/share and is funding
development through Phase II by making a series of convertible subordinated
loans. XOMA is manufacturing the product, now called hu1124, for clinical trial
use and managing clinical trials through Phase II. In April and December 1996
respectively, Genentech loaned $5.0 million and $8.5 million to fund 1996 and
1997 development costs. In December 1997, Genentech loaned an additional $10.0
million to fund 1998 development costs.

E5(R) Monoclonal Antibody Product

     In 1987, XOMA and Pfizer entered into agreements relating to a potentially
wide range of monoclonal antibody-based products for the treatment of
gram-negative sepsis. Pfizer paid XOMA an initial license fee and made payments
based on development progress. In June 1997, the Company announced that Pfizer
had decided to end its development and marketing agreements with XOMA. See
"Regulatory Process".

Other

     From time to time, the Company reviews development opportunities with other
biotechnology companies with a view toward providing process scale-up,
regulatory and/or clinical services to them.

     Competition

     The biotechnology and pharmaceutical industries are subject to continuous
and substantial technological change. Competition in the areas of recombinant
DNA-based and monoclonal antibody-based technologies is intense and expected to
increase as established biotechnology firms and large chemical and
pharmaceutical companies advance in the field. A number of these large
pharmaceutical and chemical companies have enhanced their capabilities by
entering into arrangements with or acquiring biotechnology companies or entering
into business combinations with other large pharmaceutical companies. Many of
these companies have significantly greater financial resources, larger research
and development and marketing staffs and larger production facilities than those
of XOMA. Moreover, certain of these companies have extensive experience in
undertaking preclinical testing and human clinical trials. These factors may
enable other companies to develop products and processes competitive with or
superior to those of the Company. In addition, a significant amount of research
in biotechnology is being carried out in universities and other non-profit
research organizations. These entities are becoming increasingly interested in
the commercial value of their work and may become more aggressive in seeking
patent protection and licensing arrangements. There can be no assurance that
developments by others will not render the Company's products or technologies
obsolete or uncompetitive.

     The Company is aware of an agreement between Genentech and Incyte
Pharmaceuticals, Inc. ("Incyte") pursuant to which Incyte claims to hold
worldwide rights to all Incyte and Genentech technology related to BPI. In
addition, it is possible that another company may be developing one or more
products based on BPI, and there can be no assurance that such product(s) will
not prove to be more effective than or receive regulatory approval prior to
Neuprex(TM).



                                       6
<PAGE>

     Regulatory Process

     XOMA's products are subject to comprehensive preclinical and clinical
testing requirements and to approval processes by FDA and similar authorities in
other countries. The Company's products are primarily regulated on a
product-by-product basis under the U.S. Food, Drug and Cosmetic Act and Section
351(a) of the Public Health Service Act. Most of the Company's human therapeutic
products are or will be classified as biologic products and would be subject to
regulation by CBER. Approval of a biologic for commercialization requires
licensure of the product and the manufacturing facilities.

     The FDA regulatory process is carried out in several phases. Prior to
beginning clinical testing of a proposed new biologic product, an IND is filed
with FDA. This document contains scientific information on the proposed product,
including results of testing of the product in animal and in vitro or laboratory
models. Also included is information on manufacture of the product and studies
on toxicity in animals, and a clinical protocol outlining the initial
investigation in humans.

     The initial stage of clinical testing, Phase I, ordinarily encompasses
safety, pharmacokinetics and pharmacodynamic evaluations. Phase II testing
encompasses investigation in specific disease states designed to provide
preliminary efficacy data and additional information on safety. Phase III
studies are designed to further establish clinical safety and efficacy and to
provide information allowing proper labeling of the product following approval.
Phase III studies are most commonly multicenter, randomized, placebo-controlled
trials in which rigorous statistical methodology is applied to clinical results.
Other designs may also be appropriate in specific circumstances.

     Following completion of clinical trials, a BLA (Biologics License
Application) is submitted to FDA to request marketing approval. Internal FDA
committees are formed which evaluate the application, including scientific
background information, animal and in vitro or laboratory efficacy studies,
toxicology, manufacturing facility and clinical data. During the review process,
a dialogue between FDA and the applicant is established in which FDA questions
are raised and additional information is submitted. During the final stages of
the approval process, FDA generally requests presentation of clinical or other
data before an FDA advisory committee. Also, during the later stages of review,
FDA conducts an inspection of the manufacturing facility to establish that the
product is made in conformity with good manufacturing practice. If all
outstanding issues are satisfactorily resolved and labeling established, FDA
issues a license for the product and for the manufacturing facility, thereby
authorizing commercial distribution.

     In December 1992, the Company filed an IND with FDA to begin Phase I human
testing of its Neuprex(TM) product and, in March 1993, began the testing.
Eighteen randomized, double-blind, placebo-controlled Phase I studies have been
completed and three Phase II efficacy studies were initiated in 1995. Two other
Phase II studies were initiated in 1996 and 1997.

     In August 1996, the FDA granted XOMA a Subpart E designation for the
Neuprex(TM) product for severe pediatric meningococcemia. Subpart E designation
is intended to expedite the development, evaluation and marketing of new
therapies for life-threatening and debilitating illnesses. In October 1996, XOMA
started a Phase III pivotal clinical trial to test the drug for this indication
in multiple medical centers in the United States and Canada. In January 1997,
the trial was expanded to include sites in the United Kingdom. See "Product
Areas - Neuprex(TM)".

     In November 1997, XOMA initiated a randomized, placebo-controlled,
double-blind Phase III pivotal trial to test Neuprex(TM) in patients suffering
severe hemorrhage caused by traumatic injury and a Phase I study in CF patients
who suffer recurring bacterial lung infections (exacerbations). See "Product
Areas - Neuprex(TM)".



                                       7
<PAGE>

     Other potential XOMA products will require significant additional
development, including extensive clinical testing. There can be no assurance
that any of the products under development by the Company will be developed
successfully, obtain the requisite regulatory approval or be successfully
manufactured or marketed.

     XOMA's product for the treatment of gram-negative sepsis, E5(R), was a
murine monoclonal antibody that binds and assists the body to clear bacterial
endotoxins. XOMA completed two double-blind, placebo-controlled, Phase III
studies of E5(R) involving nearly 1300 patients. In March 1989, XOMA filed a
Product License Application ("PLA") for FDA licensure of E5(R). In June 1992,
FDA informed XOMA that E5(R) was not approvable without further clinical
testing. In June 1993, a third Phase III clinical trial began with narrower
entry criteria than previous trials. In April 1997, XOMA and Pfizer decided to
discontinue this trial. In June 1997, the Company announced that Pfizer had
decided to end its marketing arrangement for E5(R).

     FDA has substantial discretion in the product approval process and it is
not possible to predict at what point, or whether, FDA will be satisfied with
the Company's submissions or whether FDA will raise questions which may delay or
preclude product approval. As additional clinical data are accumulated, they
will be submitted to FDA and may have a material impact on the FDA product
approval process. Given that regulatory review is an interactive and continuous
process, the Company has adopted a policy of limiting announcements and comments
upon the specific details of the ongoing regulatory review of its products,
subject to its obligations under the securities laws, until definitive action is
taken.

     Patents and Trade Secrets

     As a result of its ongoing activities, the Company holds and is in the
process of applying for a number of patents in the United States and abroad to
protect its products and important processes. The Company also has obtained or
has the right to obtain exclusive licenses to certain patents and applications
filed by others. However, the patent position of biotechnology companies
generally is highly uncertain and no consistent policy regarding the breadth of
allowed claims has emerged from the actions of the Patent Office with respect to
biotechnology patents. Accordingly, no assurance can be given that the Company's
patents will afford protection against competitors with similar technologies, or
that others will not obtain patents claiming aspects similar to those covered by
the Company's patent applications.

     During the period from September 1994 to December 1997, the U.S. Patent and
Trademark Office (the "Patent Office") issued twenty-one patents to the Company
related to its BPI-based products. These BPI-related patents include four
directed to novel compounds and compositions, one directed to manufacturing
methods, two directed to improved formulations and methods, three directed to
BPI and LBP assays and eleven directed to therapeutic uses of BPI protein
products, including uses of BPI in conjunction with antibiotics for the
treatment of gram-negative and gram-positive bacterial infections. U.S. Patent
No. 5,420,019 issued to the Company relates to novel recombinant amino terminal
fragments and fragment analogs of BPI and methods for their recombinant
production. The Company believes that this patent will provide comprehensive
protection for the manufacture, use and sale of its BPI-derived Neuprex(TM) and
I-PREX(TM) products in the U.S. The Company has received nine additional Notices
of Allowance from the Patent Office and has more than twenty patent applications
pending worldwide related to its BPI-based products.

     In addition to the thirty BPI-related U.S. patents and Notices of Allowance
issued to the Company, the Company is the exclusive licensee of BPI-related
patents and applications owned by NYU. These include four issued U.S. patents
and one additional U.S. Notice of Allowance, directed to novel BPI-related
protein and DNA compositions, as well as their production and uses. U.S. Patent
No. 5,198,541 issued to NYU relates to the recombinant production of BPI. The
Company believes that this patent has substantial value because it covers
certain production methodologies that allow production of commercial-scale
quantities of BPI for human use. In addition, the European Patent Office granted
to NYU, EP 375724, with claims to N-terminal BPI fragments and their use, alone
or in conjunction with antibiotics, for the treatment of conditions associated
with bacterial infections.



                                       8
<PAGE>

     Between 1992 and 1996, the Patent Office issued six patents related to BPI
to Incyte. Four of these patents originate from one initially-filed application
and are directed to endotoxin-associated uses of BPI, one patent is directed to
BPI/lipid carrier compositions and one patent relates to uses of BPI with
polymannuronic acid. Based on the opinion of its U.S. patent counsel, Marshall,
O'Toole, Gerstein, Murray & Borun, the Company believes that it does not
infringe any valid claims of any of the Incyte patents. The Company is aware
that the European Patent Office granted to Cornell and Rockefeller Universities
EP 272489 related to certain neutrophil-derived antimicrobial proteins and the
Company believes that Incyte may control this patent. The Company is aware of an
agreement between Genentech and Incyte pursuant to which Incyte claims to hold
worldwide rights to all Incyte and Genentech technology related to BPI.

     During the period from July 1991 to December 1997, the Patent Office issued
seven patents and one Notice of Allowance to the Company related to its
bacterial expression technology, including claims to novel promoter sequences,
secretion signal sequences, compositions and methods for expression and
secretion of recombinant proteins from bacteria, including immunoglobulin gene
products. U.S. Patent No. 5,028,530 issued to the Company is directed to
expression vehicles containing an AraB promoter, host cells and processes for
regulated expression of recombinant proteins. U.S. Patent No. 5,576,195 is
related to DNA encoding a pectate lyase signal sequence, recombinant vectors,
host cells and methods for production and externalization of recombinant
proteins. U.S. Patent Nos. 5,595,898, 5,698,435 and 5,618,920 address secretable
immunoglobulin chains, DNA encoding the chains and methods for their recombinant
production. U.S. Patent Nos. 5,693,493 and 5,698,417 relate to methods for
recombinant production/secretion of functional immunoglobulin fragments.
Numerous foreign patents have been granted which, along with additional pending
foreign patent applications, correspond to the patents issued and allowed in the
U.S.

     If certain patents issued to others are upheld or if certain patent
applications filed by others issue and are upheld, the Company may require
certain licenses from others in order to develop and commercialize certain
potential products incorporating the Company's technology. There can be no
assurance that such licenses, if required, will be available on acceptable
terms.

     Research and License Agreements

     XOMA has contracted with a number of academic and institutional
collaborators to conduct certain research and development. Under these
agreements the Company generally funds either the research and development or
evaluation of products, technologies or both, will own or obtain an exclusive
license to products or technologies developed, and will pay royalties on sales
of products covered by the license. The rates and durations of such royalty
payments vary by product and institution, and range generally for periods from
five years to indefinite duration. Aggregate expenses of the Company under all
of its research agreements totaled $0.2 million, $0.3 million and $0.4 million
in 1997, 1996 and 1995, respectively. The Company has entered into certain
license agreements with respect to the following products:

Bactericidal/Permeability Increasing Protein (BPI)

     In August 1990, XOMA entered into a research collaboration and license
agreement with NYU whereby XOMA obtained an exclusive license to patent rights
for DNA materials and genetic engineering methods for the production of BPI and
fragments thereof. BPI is part of the body's natural defenses against
gram-negative bacteria and XOMA is exploring the use of its Neuprex(TM) and
I-PREX(TM) products, based on BPI, for various indications. XOMA has obtained an
exclusive, worldwide license for the development, manufacture, sale and use of
BPI products for all therapeutic and diagnostic uses, and it has paid a license
fee and will make milestone payments and pay royalties to NYU on the sale of
such products. The license becomes fully-paid upon the later of the expiration
of the relevant patents or fifteen years after the first commercial sale,
subject to NYU's right to terminate for certain events of default.



                                       9
<PAGE>

Recombinant Technology

     XOMA has obtained licenses under certain Stanford University and University
of California patents relating to certain basic processes of recombinant DNA
technology. The Stanford agreement provides that the Company will pay an annual
fee and both agreements provide for royalties on sales of products should
processes used in making those product(s) come under the licensed patents.

E5(R) Monoclonal Antibody Product

     In conjunction with the decision to discontinue the Phase III E5(R)
clinical trial and the termination of Pfizer's marketing agreement with XOMA,
the Company's license agreement with the Regents of the University of California
has been terminated.

     Employees

     As of December 31, 1997 XOMA employed 160 full-time employees at its
Berkeley and Santa Monica, California facilities. The Company's employees are
engaged in clinical, manufacturing, quality assurance and control, research and
product development activities, and in executive, finance and administrative
positions. The Company considers its employee relations to be excellent.

     The Company was incorporated in Delaware in 1981. The principal executive
offices of XOMA are located at 2910 Seventh Street, Berkeley, California 94710
(telephone 510-644-1170).

Item 2.        Properties

     XOMA's principal product development and manufacturing facilities are
located in Berkeley, California. The Company leases 83,000 square feet of space
in Berkeley including approximately 35,000 square feet of research and
development laboratories, 32,000 square feet of production and production
support facilities and 16,000 square feet of office space. An additional 3,000
square feet of office space has been subleased to a third party. Separately, a
16,500 square foot production facility in Berkeley is owned by XOMA.

     XOMA also maintains offices, laboratories and a manufacturing facility
occupying approximately 15,000 square feet in leased space in Santa Monica,
California. An additional 6,000 square foot leased facility for scale-up of the
Neuprex(TM) product was completed in May 1993. The Company also owns an
approximately 6,750 square foot parking lot in Santa Monica.

Item 3.        Legal Proceedings

     In the securities class action lawsuit Warshaw, et al. v. XOMA Corporation,
et al., the defendants and plaintiffs reached an agreement on March 14, 1997 to
settle all claims for $3.75 million in cash and $2.25 million in XOMA common
stock. By order entered September 8, 1997, the United States District Court for
the Northern District of California approved the settlement. All of the cash
portion of the settlement has been paid by insurance into a settlement fund
administered by an escrow agent. The claims administration process was deemed
complete as of December 16, 1997, and on January 7, 1998, XOMA directed its
stock transfer agent to issue and distribute to authorized claimants 344,168
shares of XOMA common stock in accordance with the terms of the court-approved
settlement agreement.

Item 4.        Submission of Matters to a Vote of Security Holders

     None.



                                       10
<PAGE>

Officers

     The officers of the Company are as follows:

Name                                  Age        Title
- ----                                  ---        -----

John L. Castello                      61         Chairman  of  the  Board,
                                                   President  and  Chief
                                                   Executive Officer

Patrick J. Scannon, M.D., Ph.D.       50         Chief Scientific and Medical 
                                                   Officer and Director

Clarence L. Dellio                    51         Senior Vice President, 
                                                   Operations

Stephen F. Carroll, Ph.D.             46         Vice President, Preclinical 
                                                   Research

Peter B. Davis                        51         Vice  President, Finance
                                                   and  Chief  Financial
                                                   Officer

Marvin J. Garrett                     47         Vice President, Clinical and 
                                                   Regulatory Affairs

Bernardus Machielse                   37         Vice President, Quality 
                                                   Assurance  and Quality
                                                   Control

Christopher J. Margolin               51         Vice President, General 
                                                   Counsel and Secretary

W. C. McGregor, Ph.D.                 56         Vice President, Technical 
                                                   Development and Santa
                                                   Monica Operations

     Officers serve at the discretion of the Board of Directors. There is no
family relationship among any of the officers or directors.




                                       11
<PAGE>

                                     PART II

Item 5. Market for Registrant's Common Equity and Related Stockholder Matters

     The Company's Common Stock trades on the Nasdaq National Market under the
symbol "XOMA". The following table sets forth the quarterly range of high and
low reported sale prices of the Company's Common Stock on the Nasdaq National
Market for the periods indicated.

                                                       Price Range
                                                  High               Low
1996:
First Quarter                                 $  5-3/4          $  3-3/8
Second Quarter                                   8-1/8             3-7/8
Third Quarter                                    7-5/8            4-1/16
Fourth Quarter                                   5-7/8            3-1/16

1997:
First Quarter                                 $  7-1/4          $4-15/16
Second Quarter                                 5-11/16             3-1/8
Third Quarter                                    8-1/2             4-5/8
Fourth Quarter                                   8-1/2             4-7/8

1998:
First Quarter (through February 28, 1998)      $ 6-1/2          $  4-7/8

     On February 28, 1998, there were approximately 5,014 record holders of
XOMA's Common Stock.

     The Company has not paid dividends on its common stock. The Company
currently intends to retain any earnings for use in the development and
expansion of its business. The Company, therefore, does not anticipate paying
cash dividends on its common stock in the foreseeable future (see Note 4 to the
Financial Statements, "CAPITAL STOCK").





                                       12
<PAGE>

Item 6.        Selected Financial Data

     The following table contains selected financial information including
statement of operations and balance sheet data of XOMA for the years 1993
through 1997. The selected financial information has been derived from the
audited Financial Statements of XOMA. The selected financial information should
be read in conjunction with the Financial Statements and notes thereto set forth
beginning on page 22 of this report and "Management's Discussion and Analysis of
Financial Condition and Results of Operations" contained in Item 7 below.

<TABLE>
<CAPTION>

                                                              Year Ended December 31,
                                -------------------------------------------------------------------------------------
                                      1997             1996             1995             1994            1993
                                      ----             ----             ----             ----            ----
                                                      (In thousands, except per share amounts)
<S>                                  <C>             <C>              <C>               <C>            <C>

Statement of
Operations Data
Total revenues (1)                   $  18,383        $   3,604        $   1,165        $   1,729       $     571
Total operating costs and
     expenses(2)                        35,552           31,826           27,469           38,460          35,259
Other income or loss,
     net(3)                             (1,404)            (888)           3,832            2,104           3,381
Net loss                             $ (15,765)       $ (29,110)       $ (22,472)       $ (34,627)      $ (31,307)
                                     =========        =========        =========        =========       =========
Basic and diluted loss per
     common share                    $   (0.44)       $   (0.90)       $   (0.97)       $   (1.54)      $   (1.46)
                                     =========        =========        =========        =========       =========
Balance Sheet Data
Cash(4)                              $  55,146        $  46,982        $  26,633        $  39,985       $  70,787
Total assets                            64,776           57,675           40,878           62,429          94,131
Long-term debt (5)                      24,773           14,516            7,692              120             425
Accumulated deficit                   (354,526)        (337,195)        (307,905)        (284,847)       (249,439)
Stockholders' equity                    31,240           34,748           26,836           43,461          78,397

</TABLE>

(1)  In 1997, includes $17.0 million from the assignment of patent and royalty
     rights to Pharmaceutical Partners LLC.

(2)  In 1994, includes $2.5 million related to employee termination benefits
     associated with a restructuring.

(3)  In 1996, includes a non-recurring expense ($2.5 million) relating to a
     securities class action lawsuit settlement. Other income in 1995
     principally consists of interest income ($1.9 million), a one-time gain of
     $4.3 million related to a modification of the funding arrangement with
     Pfizer for the E5(R) clinical trial, and a $2.4 million loss related to
     write-down of property and equipment.

(4)  Includes cash, cash equivalents, short-term investments, and interest
     receivable.



                                       13
<PAGE>

     Excludes current portion. In 1997 and 1996, includes $23.5 million and
$13.5 million, respectively, aggregate principal amount of convertible
subordinated notes due to Genentech in 2005. In 1995, includes $6.5 million
aggregate principal amount of convertible debentures due 1998. As of December
31, 1996 all of the convertible debentures had been converted into 2,054,224
shares of Common Stock.

Item 7. Management's Discussion and Analysis of Financial Condition and Results
        of Operations

     Overview

     XOMA is a biopharmaceutical company developing products to treat
infections, infectious complications of traumatic injury and surgery, and
immunologic and inflammatory disorders. The Company's primary focus is on
products derived from BPI. The first BPI-derived product, Neuprex(TM) is in
Phase III pivotal trials in two indications, and earlier stage clinical trials
in additional indications. Other BPI-derived products in preclinical testing
include I-PREX(TM) a topical ophthalmic product, and Mycoprex(TM), a peptide
product targeting systemic fungal infections.

     XOMA is also developing the hu1124 humanized monoclonal antibody product
under a collaboration agreement with Genentech. The product is in Phase II
clinical testing for psoriasis. Other indications are under review. Genentech is
providing funding for development and clinical trials through a series of
long-term convertible loans.

     The Company incurred a net loss in each of the past three years and is
expected to continue to operate at a loss until regulatory approval and
commencement of commercial sales of its products. The timing of product
approvals is uncertain, and there can be no assurance that approvals will be
granted or that revenues from product sales will be sufficient to attain
profitability.

     Revenues

     Total revenues were $18.4 million in 1997, compared with $3.6 million in
1996 and $1.2 million in 1995. Revenues for 1997 consisted of $17.0 million from
the assignment of anti-CD20 antibody patents and royalty rights to
Pharmaceutical Partners, LLC and $1.4 million for various licensing
transactions. Revenues for 1996 included $3.0 million for licensing of
intellectual property related to anti-CD20 antibodies to Genentech, and for 1995
included $0.8 million in partial consideration for the sale of the Company's T
cell receptor technology.

     Costs and Expenses

     In 1997, research and development expenses increased by $3.5 million, (13%)
versus 1996, following a $4.3 million (19%) increase from 1995 to 1996. These
increases reflect higher spending on clinical trials and preparing for
regulatory applications and inspections for Neuprex(TM) and the initiation of
development work and clinical trials for hu1124. The Company anticipates
research and development expenditures to continue at similar or higher levels
throughout 1998.

     General and administrative expenses increased by $0.2 million (4%) from
1996 to 1997, following an increase of $0.1 million (1%) from 1995 to 1996.

     Annual investment income has essentially remained unchanged through the
period 1995 - 1997, as improved average cash balances each successive year have
been offset by lower prevailing interest rates. Other expense in 1997 included
interest on the convertible notes due to Genentech in 2005, which accrues
interest at six-months LIBOR plus 1%. Interest expense in 1996 included interest
on the Genentech note and also on the Company's 4% Convertible Subordinated
Debentures.



                                       14
<PAGE>

     Other Income (Expense)in 1996 included a provision of $2.5 million for
legal fees and settlement costs reflecting an agreement reached with plaintiff's
attorney in a class action law suit. An offsetting gain of $0.3 million was
realized in 1997 reflecting an adjustment to the value of the settlement. Other
Income in 1995 included a one-time gain of $1.9 million related to a
modification of the funding arrangement with Pfizer for the E5(R) clinical trial
and a write-down of property and equipment. Due to the termination of E5(R)
development, the contingent $22.4 million liability to Pfizer has been
eliminated.

     Liquidity and Capital Resources

     Cash, cash equivalents and short-term investments increased by $8.2 million
to $55.1 million at December 31, 1997. Financing activities of $21.7 million
included a $10.0 million advance from Genentech under a long-term credit
arrangement to fund 1998 development costs of hu1124, and $12.1 million net
proceeds from a private placement partially offset by principal payments under
capital lease obligations. The Company's cash, cash equivalents and short-term
investments are expected to continue to decrease while the Company pursues FDA
licensure, except to the extent the Company is able to secure additional
funding.

     Net cash used in operating activities was $12.0 million in 1997, compared
with $22.4 million in 1996 and $24.7 million in 1995. The improvement in
operating cash flows in 1997 and 1996 is due primarily to cash from licensing
transactions, which there can be no assurance will continue. Capital
expenditures for 1997, 1996 and 1995 were $1.5 million, $1.1 million and $0.4
million, respectively. A second 2750-liter fermentor train was added to XOMA's
Berkeley facility in 1997 to provide additional capacity for Neuprex(TM) and
hu1124. The Company intends to continue to fund capital spending from internal
cash resources supplemented by capital financing where appropriate and
available.

     The Company's cash position and resulting investment income are sufficient
to finance the Company's currently anticipated needs for operating expenses,
working capital, equipment and current research projects, for in excess of one
year. The Company continues to evaluate strategic alliances, potential
partnerships and financing arrangements which would further strengthen its
competitive position and provide additional funding. The Company cannot predict
whether or when any such alliance(s), partnership(s) or financing(s) will be
consummated or whether additional funding will be available when required.

     Although operations are influenced by general economic conditions, the
Company does not believe that inflation had a material impact on financial
results for the periods presented. The Company believes that it is not dependent
on materials or other resources that would be significantly impacted by
inflation or changing economic conditions in the foreseeable future.

     The Company is currently reviewing its computer systems in order to
evaluate necessary modifications for the year 2000. The Company does not
currently anticipate that it will incur material expenditures to complete any
such modifications. The Company can provide no assurance that there will be no
year 2000 impact through third parties, such as suppliers of raw materials for
manufacturing and clinical research organizations.

     Forward-Looking Statements

     Certain statements contained herein that are not related to historical
facts may constitute "forward-looking" information, as that term is defined in
the Private Securities Litigation Reform Act of 1995. Such statements are based
on the Company's current beliefs as to the outcome and timing of future events,
and actual results may differ materially from those projected or implied in the
forward-looking statements. Further, certain forward-looking statements are
based upon assumptions of future events which may not prove accurate. The
forward-looking statements involve risks and uncertainties including, but not
limited to, results of pending or future clinical trials, actions by the U.S.
Food and Drug Administration, changes in the status of the Company's
collaborative relationships, and future actions by the U.S. Patent and Trademark
Office, as well as 



                                       15
<PAGE>

more general risks and uncertainties related to regulatory approvals, product
efficacy and development, the Company's financing needs and opportunities,
scale-up and marketing capabilities, intellectual property protection,
competition, stock price volatility and other risk factors referred to herein
and in other of the Company's Securities and Exchange Commission filings.

Item 7a.      Quantitative and Qualitative Disclosures About Market Risk.

     Not applicable until the Company's 1998 fiscal year.

Item 8.        Financial Statements and Supplementary Data

     The following consolidated financial statements of the registrant, related
notes, and report of independent public accountants are set forth beginning on
page 21 of this report.

         Report of Independent Public Accountants
         Balance Sheets
         Statements of Operations
         Statements of Stockholders' Equity
         Statements of Cash Flows
         Notes to Financial Statements

Item 9.        Change in Accountants

     On March 19, 1998, the Company appointed Ernst & Young, LLP ("Ernst &
Young") to serve as the Company's independent accountants for 1998, the
ratification of which appointment will be submitted to the stockholders at the
Company's 1998 annual meeting.

     From fiscal 1983 through fiscal 1997, Arthur Andersen, LLP ("Arthur
Andersen") acted as the Company's independent accountants. Arthur Andersen was
dismissed on March 19, 1998. The decision to change accountants was approved by
the audit committee of the Board of Directors. The reports of Arthur Andersen on
the financial statements of the Company for the two most recent fiscal years did
not contain any adverse opinion or disclaimer of opinion and were not qualified
or modified as to uncertainty, audit scope or accounting principles. During the
Company's two most recent fiscal years and all subsequent interim periods
preceding such dismissal, there were no disagreements with Arthur Andersen on
any matter of accounting principles or practices, financial statement
disclosure, or auditing scope or procedure, which disagreements, if not resolved
to the satisfaction of Arthur Andersen, would have caused it to make a reference
to the subject matter of disagreements in connection with its reports; nor has
Arthur Andersen ever presented a written report, or otherwise communicated in
writing to the Company or Board of Directors or the audit committee thereof the
existence of any "disagreement" or "reportable event" within the meaning of Item
304 of Regulation S-K.

     The Company has authorized Arthur Andersen to respond fully to the
inquiries of Ernst & Young. The letter from Arthur Andersen addressed to the
Securities and Exchange Commission (the "SEC"), as required by Item 304 (a) (3)
of Regulation S-K, will be filed as an exhibit to this Annual Report on Form
10-K by amendment.





                                       16
<PAGE>

                                    PART III

Item 10.       Directors and Executive Officers of the Registrant

     The section labeled "Proposal 1 -- Election of Directors" appearing in the
Company's proxy statement for the 1998 annual meeting of stockholders is
incorporated herein by reference. Information concerning the Company's executive
officers is set forth in Part I of this Report on Form 10-K.

Item 11.       Executive Compensation

     The section labeled "Compensation of Executive Officers" appearing in the
Company's proxy statement for the 1998 annual meeting of stockholders is
incorporated herein by reference.

Item 12.       Security Ownership of Certain Beneficial Owners and Management

     The section labeled "Stock Ownership" appearing in the Company's proxy
statement for the 1998 annual meeting of stockholders is incorporated herein by
reference.

Item 13.       Certain Relationships and Related Transactions

     The section labeled "Certain Transactions" appearing in the Company's proxy
statement for the 1998 annual meeting of stockholders is incorporated herein by
reference.





                                       17
<PAGE>

                                     PART IV

Item 14. Exhibits, Financial Statement Schedules and Reports on Form 8-K

          (a) List of documents filed as part of this Report.

               (1) Financial Statements:

                    All financial statements of the registrant referred to in
                    Item 8 of this Report on Form 10-K.

               (2)  Financial Statement Schedules:

                    All financial statements schedules have been omitted because
                    the required information is included in the financial
                    statements or the notes thereto or is not applicable or
                    required.

               (3)  Exhibits:

                    See "Index to Exhibits".

          (b)  Reports on Form 8-K.

               Current Report on Form 8-K filed with the SEC on August 18, 1997.

               Current Report on Form 8-K filed with the SEC on January 9, 1998.





                                       18
<PAGE>

                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, on this 19th day of
March, 1998.

                                 XOMA CORPORATION


                                 By /s/ JOHN L. CASTELLO
                                    --------------------------------------
                                        John L. Castello,
                                        Chairman of the Board, President
                                        and Chief Executive Officer

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
registrant and in the capacities and on the dates indicated.

<TABLE>
<CAPTION>

Signature                                   Title                                 Date
- ---------                                   -----                                 ----
<S>                                         <C>                                   <C>

/s/ JOHN L. CASTELLO                        Chairman of the Board, President      March 19, 1998
- -----------------------------               and Chief Executive Officer

/s/ PATRICK J. SCANNON                      Chief Scientific and Medical          March 19, 1998
- -----------------------------               Officer and Director

/s/ PETER B. DAVIS                          Vice President, Finance and Chief     March 19, 1998
- -----------------------------               Financial Officer (Principal
                                            Financial and Accounting Officer)

/s/ JAMES G. ANDRESS                        Director                              March 19, 1998
- -----------------------------
(James G. Andress)

/s/ WILLIAM K. BOWES, JR.                   Director                              March 19, 1998
- -----------------------------
(William K. Bowes, Jr.)

/s/ ARTHUR KORNBERG                         Director                              March 19, 1998
- -----------------------------
(Arthur Kornberg)

/s/ STEVEN C. MENDELL                       Director                              March 19, 1998
- -----------------------------
(Steven C. Mendell)

/s/ W. DENMAN VAN NESS                      Director                              March 19, 1998
- -----------------------------
(W. Denman Van Ness)

</TABLE>



                                       19
<PAGE>

                          INDEX TO FINANCIAL STATEMENTS
                                                                 Page

Report of Independent Public Accountants......................    21
Balance Sheets................................................    22
Statements of Operations......................................    23
Statements of Stockholders' Equity............................    24
Statements of Cash Flows......................................    25
Notes to Financial Statements.................................    26





                                       20
<PAGE>

                    REPORT OF INDEPENDENT PUBLIC ACCOUNTANTS

To XOMA Corporation:

     We have audited the accompanying balance sheets of XOMA Corporation (a
Delaware corporation) as of December 31, 1997 and 1996 and the related
statements of operations, stockholders' equity and cash flows for each of the
three years in the period ended December 31, 1997. These financial statements
are the responsibility of the Company's management. Our responsibility is to
express an opinion on these financial statements based on our audits.

     We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also includes
assessing the accounting principles used and significant estimates made by
management, as well as evaluating the overall financial statement presentation.
We believe that our audits provide a reasonable basis for our opinion.

     In our opinion, the financial statements referred to above present fairly,
in all material respects, the financial position of XOMA Corporation as of
December 31, 1997 and 1996, and the results of its operations and its cash flows
for each of the three years in the period ended December 31, 1997 in conformity
with generally accepted accounting principles.


     San Francisco, California                       ARTHUR ANDERSEN LLP 
     February 3, 1998





                                       21
<PAGE>

<TABLE>
<CAPTION>
                                               XOMA CORPORATION

                                                BALANCE SHEETS
                                 (In thousands, except par and share amounts)

                                               ASSETS
                                                                                       December 31
                                                                                       -----------
                                                                                1997                 1996
                                                                                ----                 ----
<S>                                                                           <C>                   <C>

CURRENT ASSETS:
  Cash and cash equivalents                                                   $  37,225             $  1,213
  Short-term investments                                                         17,921               45,769
  Related party receivables                                                         263                  253
  Other receivables                                                                  88                  548
  Prepaid expenses and other                                                        142                  219
    Total current assets                                                         55,639               48,002
                                                                              ---------             --------
NON-CURRENT ASSETS:
Property and equipment, net
  Assets held for sale                                                            4,442                4,442
  Deposits and other                                                                131                  133
                                                                              ---------             --------
                                                                              $  64,776             $ 57,675
                                                                              =========             ========
                                LIABILITIES AND STOCKHOLDERS' EQUITY

CURRENT LIABILITIES:
  Accounts payable                                                            $   1,644            $   1,778
  Accrued liabilities                                                             6,412                6,144
  Capital lease obligations due within one year                                     707                  489
                                                                              ---------            ---------
    Total current liabilities                                                     8,763                8,411
                                                                              ---------            ---------
NON-CURRENT LIABILITIES:
  Capital lease obligations due after one year                                       --                  703
  Convertible notes                                                              24,773               13,813
                                                                              ---------            ---------
    Total non-current liabilities                                                24,773               14,516
                                                                              ---------            ---------
COMMITMENTS AND CONTINGENCIES (Note 6)
STOCKHOLDERS' EQUITY:
     Preferred stock, $.05 par value, 1,000,000 shares authorized, 1,167 and 0
         outstanding (liquidation preference $11,670 and $0) at December 31,
         1997 and
         1996, respectively                                                          --                   --
     Common stock, $.0005 par value, 70,000,000 shares
         authorized, 39,891,104 and 39,609,275 outstanding at
         December 31, 1997 and 1996, respectively                                    20                   20
  Paid-in capital                                                               385,746              371,923
  Accumulated deficit
                                                                               (354,526)            (337,195)
                                                                              ---------            ---------
    Total stockholders' equity                                                   31,240               34,748
                                                                              ---------            ---------
                                                                              $  64,776            $  57,675
                                                                              =========            =========
</TABLE>

   The accompanying notes are an integral part of these financial statements.




                                       22
<PAGE>
<TABLE>
<CAPTION>

                                               XOMA CORPORATION

                                           STATEMENTS OF OPERATIONS
                                   (In thousands, except per share amounts)

                                                                              Years ended December 31
                                                              --------------------------------------------------------
                                                                    1997               1996               1995
                                                                    ----               ----               ----
<S>                                                              <C>                <C>               <C>

REVENUES:
  Product sales and royalties                                     $     56           $     61         $     87
  Research and development fees
     Collaborative agreements                                          250                 --               --
     License fees                                                   18,077              3,543            1,078
                                                                  --------           --------         --------
        Total revenues                                              18,383              3,604            1,165
                                                                  --------           --------         --------
OPERATING COSTS AND EXPENSES:
  Research and development                                          29,878             26,371           22,086
  General and administrative                                         5,674              5,455            5,383
                                                                  --------           --------         --------
     Total operating costs and expenses                             35,552             31,826           27,469
                                                                  --------           --------         --------
     Loss from operations                                          (17,169)           (28,222)         (26,304)
OTHER INCOME (EXPENSE):
  Investment income                                                  2,120              2,011            1,934
  Litigation settlement                                                 --             (2,500)              --
  Other income(expense)                                               (716)              (399)           1,898
                                                                  --------                            --------
      Net loss                                                    $(15,765)          $(29,110)        $(22,472)
                                                                  =========          ========         ========
BASIC AND DILUTED NET LOSS PER COMMON                             $  (0.44)          $  (0.90)        $  (0.97)
  SHARE                                                           =========          ========         ========
WEIGHTED AVERAGE COMMON SHARES
  OUTSTANDING                                                       39,679             32,493           23,671
                                                                  =========          ========         ========
</TABLE>

   The accompanying notes are an integral part of these financial statements.





                                       23
<PAGE>

<TABLE>
<CAPTION>
                                XOMA CORPORATION
                       STATEMENTS OF STOCKHOLDERS' EQUITY
                                 (In thousands)

                                                                                                                         Total
                                                                                             Paid-in    Accumulated   Stockholders'
                                                Common Stock          Preferred Stock        Capital     Deficit        Equity
                                            Shares        Amount    Shares       Amount

<S>                                         <C>           <C>        <C>         <C>       <C>         <C>            <C>

BALANCE, DECEMBER 31, 1994                    22,174       $11         16         $ 1    $328,296     $(284,847)   $ 43,461
   Exercise of stock options                      25        --         --          --          11            --          11
   Contributions to 401(k) and management
     incentive plans                             149        --         --          --         434            --         434
   Sale of common stock                          471         1         --          --         717            --         718
   Amortization of deferred compensation          --        --         --          --         214            --         214
   Sale of preferred stock                        --        --          5          --       4,143            --       4,143
   Conversion of preferred stock               4,230         2        (13)         (1)         (1)           --          --
   Exercise of warrants                            1        --         --          --           7            --           7
   Unrealized gain (loss) on investments          --        --         --          --         125            --         125
   Dividends on preferred stock                  253        --         --          --         781          (586)        195
   Net loss                                       --        --         --          --          --       (22,472)    (22,472)
                                              ------       ---        ---         ---    --------     ---------    --------
BALANCE, DECEMBER 31, 1995                    27,303        14          8          --     334,727      (307,905)     26,836

   Exercise of stock options                      72        --         --          --         207            --         207
   Contributions to 401(k) and management
     incentive plans                              90        --         --          --         395            --         395
   Sale of common stock                        2,123         1         --          --      10,651            --      10,652
   Amortization of deferred compensation          --        --         --          --          37            --          37
   Sale of preferred stock                        --        --          7          --      18,966            --      18,966
   Issuance of warrants                           --        --         --          --         800            --         800
   Conversion of preferred stock               7,914         4        (15)         --          (4)           --          --
   Conversion of debentures                    2,054         1         --          --       5,919            --       5,920
   Unrealized gain (loss) on investments          --        --         --          --          45            --          45
   Dividends on preferred stock                   53        --         --          --         180          (180)         --
   Net loss                                       --        --         --          --          --       (29,110)    (29,110)
                                              ------       ---        ---         ---    --------     ---------    --------
BALANCE, DECEMBER 31, 1996                    39,609        20         --          --     371,923      (337,195)     34,748

   Exercise of stock options                      53        --         --          --         143            --         143
   Contributions to 401(k) and management
     incentive plans                              57        --         --          --         319            --         319
   Sale of preferred stock                        --        --          1          --      10,936            --      10,936
   Conversion of preferred stock                 169        --         --          --          --            --          --
  Issuance of warrants                            --        --         --          --       1,125            --       1,125
   Unrealized gain (loss) on investments          --        --         --          --         (42)           --         (42)
   Dividends on preferred stock                    3        --         --          --       1,342        (1,566)       (224)
   Net loss                                       --        --         --          --          --       (15,765)    (15,765)
                                              ------       ---        ---         ---    --------     ---------    --------
BALANCE, DECEMBER 31, 1997                    39,891       $20          1         $--    $385,746     $(354,526)   $ 31,240
                                              ======       ===        ===         ===    ========     =========    ========
</TABLE>

   The accompanying notes are an integral part of these financial statements.




                                       24
<PAGE>
<TABLE>
<CAPTION>

                                XOMA CORPORATION
                            STATEMENTS OF CASH FLOWS
                                 (In thousands)

                                                                         Years ended December 31,
                                                         ------------------------------------------------------
                                                             1997               1996                 1995
                                                             ----               ----                 ----
<S>                                                        <C>                 <C>                 <C>

 CASH FLOWS FROM OPERATING ACTIVITIES:
    Net loss                                               $(15,765)          $ (29,110)           $(22,472)
    Adjustments to reconcile net loss to net cash
      used in operating activities:
      Depreciation and amortization                           2,032               2,131               2,920
      Inventory reserve                                          --                  --               4,170
      Write-down of assets held for sale                         --                  --               2,400
      Deferred compensation expense                              --                  37                 214
      Loss (gain) on retirement of property and                  21                   2                (145)
      equipment
 Changes in assets and liabilities:
    Decrease (increase) in related party and                    450               1,742              (2,116)
      other receivables
    Decrease (increase) in prepaid expenses                      77                  (9)                612
    Decrease (increase) in deposits and other                     2                  --               1,350
      assets
    Increase (decrease) in accounts payable                    (134)               (342)                705
    Increase (decrease) in accrued liabilities                1,331               3,124              (3,921)
    Increase (decrease) in non-current liabilities              --                 --                (8,465)
                                                           --------           ---------            --------
         Total adjustments                                    3,779               6,685              (2,276)
                                                           --------           ---------            --------
         Net cash used in operating activities              (11,986)            (22,425)            (24,748)
                                                           --------           ---------            --------
 CASH FLOWS FROM INVESTING ACTIVITIES:
    Proceeds from sale of short-term investments            105,195              89,675              61,942
    Payments for purchase of short-term                     (77,389)           (129,073)            (31,641)
      investments
    Purchase of property and equipment, net of
      proceeds                                               (1,519)             (1,050)               (350)
                                                           --------           ---------            --------
      Net cash provided by (used in) investing               26,287             (40,448)             29,951
                                                           --------           ---------            --------
      activities
 CASH FLOWS FROM FINANCING ACTIVITIES:
    Proceeds from sale and leaseback                             --                  --               1,800
    Principal payments under capital lease                     (485)               (546)               (488)
      obligations
    Proceeds from issuance of debentures                      9,992              13,545               5,858
    Proceeds from issuance of common or preferred
      stock                                                  12,204              30,687               4,451
                                                           --------           ---------            --------
      Net cash provided by financing activities              21,711              43,686              11,621
                                                           --------           ---------            --------
      Net increase (decrease) in cash and cash
        equivalents                                          36,012             (19,187)             16,824
    Cash and cash equivalents at beginning of year            1,213              20,400               3,576
                                                           --------           ---------            --------
    Cash and cash equivalents at end of year               $ 37,225           $   1,213            $ 20,400
                                                           ========           =========            ========
</TABLE>

   The accompanying notes are an integral part of these financial statements.




                                       25
<PAGE>

                                XOMA CORPORATION
                          NOTES TO FINANCIAL STATEMENTS


1.       OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Business

     XOMA Corporation ("XOMA" or the "Company") is a biopharmaceutical company
developing products to treat infections, infectious complications of traumatic
injury and surgery, and immunologic and inflammatory disorders. The Company's
products are presently in various stages of development and all are subject to
regulatory approval before the Company can commercially introduce any products.
There can be no assurance that any of the products under development by the
Company will be developed successfully, obtain the requisite regulatory approval
or be successfully manufactured or marketed.

     The Company's cash position and resulting investment income are sufficient
to finance the Company's currently anticipated needs for operating expenses,
working capital, equipment and current research projects for in excess of one
year. The Company continues to evaluate strategic alliances, potential
partnerships, and financing arrangements which would further strengthen its
competitive position and provide additional funding. The Company cannot predict
whether or when any such alliance(s), partnership(s) or financing(s) will be
consummated or whether additional funding will be available when required.

Estimates

     The preparation of financial statements in conformity with generally
accepted accounting principles requires management to make estimates and
assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting period. Actual results could differ materially from those estimates.

Net Loss Per Common Share

     Net loss per common share is based on the weighted average number of common
shares outstanding in accordance with Financial Accounting Standard No. 128.





                                       26
<PAGE>

     Reconciliation of the numerator and the denominator of basic and diluted
net loss per share was derived as follows (in thousands, except per share
amounts):
<TABLE>
<CAPTION>

                                                                                                   Amount per
Year ended December 31                                     Loss                 Shares                share
<S>                                                     <C>                  <C>                    <C>


                      1997
Net loss                                                $(15,765)
Preferred stock dividends                                 (1,566)
                                                        --------
Basic and diluted loss available to common
shareholders                                            $(17,331)               39,679                $(0.44)
                                                        ========

                      1996
Net loss                                                $(29,110)
Preferred stock dividends                                   (180)
                                                        --------
Basic and diluted loss available to common
shareholders                                            $(29,290)               32,493                $(0.90)
                                                        ========

                      1995
Net loss                                                $(22,472)
Preferred stock dividends                                   (586)
                                                        --------
Basic and diluted loss available to common
shareholders                                            $(23,058)               23,671                $(0.97)
                                                        ========

     The following potentially dilutive outstanding securities were not
considered in the computation of basic and diluted loss per share because they
would be antidilutive for each of the years ended December 31:

Amount (in thousands):                                     1997                  1996                 1995
- ---------------------                                      ----                  ----                 ----

Weighted average options for shares of
   common stock                                            3,627                3,162                 2,992

Weighted average warrants for shares of
   common stock                                              295                   29                   983

Common shares issuable to satisfy obligations                344                   --                    --

Shares of convertible preferred stock                      1,167                   --                 7,807

Convertible notes, debentures, and related
   interest                                              $24,773              $13,813                $6,500

</TABLE>

     Subsequent to December 31, 1997 the Company issued 344,168 shares of common
stock in settlement of a securities class action lawsuit(see Note 6).

Cash and Cash Equivalents

     For the purpose of the statements of cash flows, the Company considers all
highly liquid debt instruments with maturities of three months or less at the
time the Company acquires them to be cash equivalents, except when such debt
instruments are part of a portfolio of investments managed by an independent,
outside investment manager, in which case these instruments are classified as
short-term investments.



                                       27
<PAGE>

Supplemental Cash Flow Information

     Cash paid for interest was $0.1 million, $0.2 million, and $0.1 million
during the years ended December 31, 1997, 1996, and 1995, respectively.

     In addition, during the years ended December 31, 1997, 1996 and 1995, the
Company had the following non-cash financing and investing activities (in
thousands):

<TABLE>
<CAPTION>
                                                                   1997             1996             1995
                                                                   ----             ----             ----

<S>                                                               <C>              <C>              <C>

Stock contribution to the 401(k) and management                   $  319            $  395          $  434
   incentive plans (Notes 4 and 9)
Stock issuance cost paid with common or preferred                     --                --               8
   stock (Note 4)
Unrealized loss(gain) on investments                                 (42)              (45)            125
Conversion of debentures to common stock                                                --           5,861
Interest paid in common stock                                         --                59              --
Conversion of preferred stock to common stock                        830            28,807          12,607
Dividends paid in common stock                                        15               180             781

</TABLE>

Property and Equipment

     Property and equipment, including equipment under capital leases, are
stated at cost. Equipment depreciation is calculated using the straight-line
method over the estimated useful lives of the assets (five to seven years).
Leasehold improvements, buildings, and building improvements are amortized and
depreciated using the straight-line method over the shorter of the lease terms
or the useful lives (one to seven years).

     Property and equipment consist of the following (in thousands):

                                                             December 31
                                                        1997            1996
                                                        ----            ----
Equipment                                              $15,545        $14,500
Leasehold and building improvements                     14,836         14,483
Construction-in-progress                                    97            208
                                                       -------        -------
                                                        30,478         29,191
Less accumulated depreciation and amortization          25,914         24,093
                                                       -------        -------
Property and equipment, net                            $ 4,564        $ 5,098
                                                       =======        =======

Assets held for sale                                   $ 4,442        $ 4,442
                                                       =======        =======


     The Company owns a facility originally intended for the production of CD5
Plus(TM) intermediates, which was re-classified as an asset held for sale in
1995 and written down to an estimated realizable value of $4.4 million resulting
in a charge to Other income and expense of $2.4 million. The amount the Company
will ultimately realize could differ materially from the amount assumed in
arriving at the realizable value.




                                       28
<PAGE>

Accrued Liabilities

     Accrued liabilities consist of the following (in thousands):

                                                       December 31
                                                  1997            1996
                                                  ----            ----

Accrued legal costs                              $  198          $  661
Accrued dividends                                   810             586
Accrued payroll costs                             1,986           1,573
Provision for litigation settlement               2,028           2,500
Clinical trial costs                              1,203             521
Other                                               187             303
                                                 ------          ------
                                                 $6,412          $6,144
                                                 ======          ======

     Activities through December 31, 1997 affecting the provision for litigation
settlement established in 1996 are as follows (in millions):

Original amount                                                 $2.5
Charges against the accrual                                      0.2
Adjustment to the accrual                                        0.3

     In December 1997, the Company elected to settle the claim through the
issuance of 344,168 shares of common stock which resulted in a $0.3 million
reduction in the accrual. The liability was eliminated in January 1998 upon
issuance of the shares.

Research and Development Fees

     Research and development fees are recognized as revenues as research
activities are performed or as development milestones are completed under the
terms of research and development agreements. The excess of total research and
development expense over revenues recognized under collaborative agreements
amounted to $29.9 million, $26.4 million, and $22.1 million for the years 1997,
1996, and 1995, respectively.

Reclassifications

     Certain reclassifications have been made to conform the prior years to the
1997 presentation.

New Accounting Standards

     In June 1997, the Financial Accounting Standards Board issued a final
statement on reporting comprehensive income. The adoption of the standard as
required on January 1, 1998 will not have a material impact on the Company's
financial statements.

2.       CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

     On December 31, 1997 and 1996, cash and cash equivalents consisted mostly
of money market mutual funds.

     The Company follows a policy of investing only in marketable debt
securities and holding them to maturity; however, since the Company has from
time to time sold certain securities to meet cash requirements or improve
investment diversification, the Company's short-term investments have been
categorized as available-for-sale.





                                       29
<PAGE>

     The aggregate fair values, amortized cost, gross unrealized holding gain,
and gross unrealized holding loss of the major types of debt securities at
December 31, 1997 were as follows (in millions):

<TABLE>
<CAPTION>
                                                                         Gross Unrealized Holding
                                            Fair           Amortized
                                            Value             Cost            Gain         Loss
<S>                                         <C>              <C>             <C>            <C>

U.S. Treasury Securities                    $9.5              $9.5           $ --           $ --
Corporate Bonds and Other                    8.4               8.4             --             --
</TABLE>

     The contractual maturities of the Company's debt securities as of December
31, 1997 were as follows (in millions):

Less than 1 year                                 $11.4
From 1 to 2 years                                  4.0
More than 2 years                                  2.5

     During the year ended December 31, 1997, gross realized losses on
available-for-sale securities were negligible and the net change in the
unrealized gain or loss was negligible. Gross realized gains were negligible.
Gains and losses are determined on a specific identification basis. As of
December 31, 1997, short-term investments included $0.1 million in certificates
of deposit which guaranteed a standby letter of credit.

3.       RESEARCH AND DEVELOPMENT AGREEMENTS

     In April 1996, the Company entered into a collaborative agreement with
Genentech, Inc. ("Genentech") to jointly develop hull24 (anti-CD11a), for
treatment of psoriasis and for organ transplant rejection. In connection
therewith, Genentech purchased 1.5 million shares of common stock for
approximately $9 million and has agreed to fund the Company's development costs
for hull24 until the completion of Phase II clinical trials through a series of
convertible subordinated notes. During 1996, Genentech made loans totaling $13.5
million ($5.0 and $8.5 million, respectively, for funding 1996 and 1997 clinical
trials and development costs) to XOMA under this arrangement. An additional loan
of $10.0 million was made in December 1997 to fund 1998 costs. Under the terms
of the agreement, the Company will scale up and develop hull24 and bring it
through Phase II clinical trials. After completion of Phase II trials, Genentech
will determine the product's future development strategy.

     In May 1996, the Company announced the granting of an exclusive license to
Genentech, including a sublicense to IDEC Pharmaceuticals Corporation, to
intellectual property covering the therapeutic use of chimeric IgG1 antibodies
specific to the CD20 antigen on the surface of human B-cells. The Company
received an initial cash payment of $3.0 million and the right to receive
royalties on the sale of products employing the anti-CD20 technology that are
sold in the United States and in other countries where the Company held relevant
patents. In December 1997, the Company assigned the related patents and royalty
rights to Pharmaceutical Partners, LLC for $17.0 million and recognized this
amount as license fee revenue.

     In June 1994, the Company assigned its exclusive worldwide rights in T cell
receptor ("TCR") peptide technology to Connetics. The Company received a
promissory note in the amount of $1.4 million and warrants to purchase 450,000
shares of Connetics. stock, and will receive milestone payments and royalties on
product sales. In 1995, the Company received an additional note in the amount of
$0.8 million pursuant to the terms of the original assignment. The notes were
paid in full in February 1996 and the warrants cancelled.

     In 1995, XOMA and Pfizer modified the funding arrangement of the then
current E5(R) clinical trial and of certain patent litigation costs. As a
result, the Company recorded a $4.3 million gain in Other income. 



                                       30
<PAGE>

In June 1997, the Company announced that Pfizer had ended its agreements with
the Company relating to monoclonal antibody-based products for the treatment of
gram-negative sepsis, which resulted in the elimination of the contingent $22.4
million liability to Pfizer.

     XOMA has granted licenses to a number of biotechnology and pharmaceutical
companies for use of patented and proprietary technologies relating to a
bacterial expression system used to manufacture recombinant pharmaceutical
products. Licensees include: Affymax Research Institute, Cantab Pharmaceuticals
Research Ltd, Eli Lilly and Company, Enzon, Inc., the Hoechst Group, ICOS
Corporation, Pasteur Merieux Serums & Vaccins, and The Pharmacia & Upjohn Group.

4.       CAPITAL STOCK

Common Stock

     In April 1996, Genentech purchased 1.5 million shares of common stock for
approximately $5.90 per share in connection with the collaborative agreement to
develop jointly Genentech's anti-CD11a monoclonal antibody product, hull24.

     In March 1996, the Company completed a private placement exempt from
registration under the Securities Act of 1933 in reliance on Regulation D
thereunder, issuing 606,061 shares of Common Stock for net proceeds of $1.9
million.

     In June and July 1995, the Company issued 470,859 shares of Common Stock in
reliance on Regulation S for net proceeds of $0.7 million.

Preferred Stock

     In August 1997, the Company completed a private placement exempt from
registration under the Securities Act of 1933 in reliance on Section 4(2)
thereof, issuing 1,250 shares in the form of 5% Convertible Preferred Stock,
Series G ("Series G Preferred") for proceeds of approximately $12.1 million net
of cash issuance costs. The same investors have also committed to provide
additional financing of up to $12.5 million at XOMA's option, subject to certain
conditions.

     Conversions of Series G Preferred will be based on the price of Common
Stock at the time of conversion. There is no initial discount on the conversion
price, but a discount of 2% will be added for each month the Series G Preferred
is held, up to a maximum discount of 14%, for which an additional $1.3 million
has been added to dividends and charged to Paid-in capital as of December 31,
1997. No conversions were permitted below a price of $7.80 for the first 60
days. The maximum conversion price for the first six months was $9.10. There are
certain restrictions on the volume of sales of underlying Common Stock by the
investors. The investors also received three-year warrants to purchase up to a
total of 432,000 common shares at a price of $10.00 per share. The additional
funding commitment also provides for limits on conversion price and trading, and
additional warrants, all based on the market price of Common Stock at the time
such funding is provided. Additional warrants to purchase 54,000 common shares
at the $10.00 price were issued to the placement agents.

     In September 1996, the Company completed a private placement exempt from
registration under the Securities Act of 1933 in reliance on Regulation D
thereunder, issuing 1,600 shares of its Convertible Preferred Stock, Series F
("Series F Preferred") for proceeds of approximately $15.0 million net of
issuance costs. As of December 31, 1996, all of the Series F Preferred, plus
accrued dividends, had been converted into 5,269,870 shares of Common Stock.



                                       31
<PAGE>

     In March 1996, the Company completed a private placement exempt from
registration under the Securities Act of 1933 in reliance on Regulation D
thereunder, issuing 5,000 shares of its Convertible Preferred Stock, Series D
("Series D Preferred") for proceeds of $4.8 million net of issuance costs. As of
September 30, 1996, all of the Series D Preferred, plus accrued dividends, had
been converted into 1,048,610 shares of Common Stock.

     In August 1995, the Company issued 4,799 shares of its Convertible
Preferred Stock, Series C ("Series C Preferred") to foreign investors in an
offering exempt from registration under the Securities Act of 1933 in reliance
on Regulation S thereunder. The offering yielded proceeds to the Company of $4.1
million net of issuance costs. As of December 31, 1995, all of the Series C
Preferred, plus accrued dividends, had been converted into 2,728,190 shares of
Common Stock.

     In December 1993, the Company issued 18,775 shares of Senior Convertible
Preferred Stock, Series B ("Series B Preferred") to two investors for proceeds
of $17.7 million net of issuance costs. Costs of the issue were approximately
$1.1 million. An additional 250 shares of Series B Preferred were issued to the
placement agent as part of the fee for investment banking services.

     In May 1994, the placement agent converted all 250 of its shares of
preferred stock into 47,595 shares of Common Stock. The amounts payable as
dividends at December 31, 1994 were paid with 252,745 shares of common stock in
January of 1995. During 1995, 7,808 shares of the Series B Preferred had been
converted into 1,501,731 shares of Common Stock. The remaining 7,807 shares were
converted into 1,648,115 shares of Common Stock in 1996 prior to the June 1996
dividend date.

     The Company has authorized 650,000 shares of Series A Cumulative Preferred
Stock of which none were outstanding at December 31, 1997, 1996 and 1995. (See
"Stockholder Rights Plan", below.)

Convertible Notes and Debentures

     Under the arrangement with Genentech (see Note 3) the Company receives
funding for development of hull24 in the form of convertible subordinated notes
due 2005 at interest rates of LIBOR plus 1% compounded and reset at the end of
June and December each year. Interest is payable at maturity. The Company has
received $5.0 million and $8.5 million of these loans, respectively, in April
and December of 1996, and a further $10.0 million in December 1997. The notes
are convertible into one share of Series E Preferred Stock (7,500 shares are so
designated) for each $10,000 in notes. The Series E Preferred Stock is
convertible into common stock. The cumulative amount of interest accrued was
$1.2 million and $0.3 million as of December 31, 1997 and 1996, respectively.

     In November 1995, the Company issued $6.5 million aggregate principal
amount of 4% Convertible Subordinated Debentures due in 1998 to foreign
investors in an offering exempt from registration under the Securities Act of
1933 in reliance on Regulation S thereunder. The offering yielded net proceeds
to the Company of $5.9 million net of issuance costs. During the first quarter
of 1996 all of the Debentures, plus accrued interest, were converted into
2,054,224 shares of Common Stock. Unamortized issuance costs of $0.6 million
were charged to Paid-in capital in connection with the conversions of the
Debentures.

Management Incentive Compensation Plan

     The Board of Directors of the Company established a Management Incentive
Compensation Plan effective July 1, 1993 (as amended, the "Incentive Plan"), in
which management employees (other than the Chief Executive Officer), as well as
certain additional discretionary participants chosen by the Chief Executive
Officer, are eligible to participate.



                                       32
<PAGE>

     Awards under the Incentive Plan vest over a three-year period with 50% of
each award payable on a date to be determined, expected to be in the first
quarter of the following fiscal year, and 25% payable on each of the next two
annual distribution dates, so long as the participant continues to participate
in the Incentive Plan.

     The amounts charged to expense under the Incentive Plan were $0.8 million,
$0.7 million and $0.6 million for the plan years 1997, 1996 and 1995
respectively.

Stockholder Rights Plan

     In October 1993, the Company's Board of Directors unanimously adopted a
Stockholder Rights Plan (the "Rights Plan"). Under the Rights Plan, Preferred
Stock Purchase Rights ("Rights") were distributed as a dividend at the rate of
one Right for each share of the Company's Common Stock held of record as of the
close of business on November 12, 1993. Each Right entitles the registered
holder of Common Stock to buy a fraction of a share of the new series of
Preferred Stock (the "Series A Preferred Stock") at an exercise price of $30.00,
subject to adjustment. The Rights will be exercisable, and will detach from the
Common Stock, only if a person or group acquires 20 percent or more of the
Common Stock, announces a tender or exchange offer that if consummated will
result in a person or group beneficially owning 20 percent or more of the Common
Stock, or if the Board of Directors declares a person or group owning 10 percent
or more of the outstanding shares of Common Stock to be an Adverse Person (as
defined in the Rights Plan). Once exercisable, each Right will entitle the
holder (other than the acquiring person) to purchase units of Series A Preferred
Stock (or, in certain circumstances, common stock of the acquiring person) with
a value of twice the Rights exercise price. The Company will generally be
entitled to redeem the Rights at $.001 per Right at any time until the close of
business on the tenth day after the Rights become exercisable. The Rights will
expire at the close of business on December 31, 2002.

5.       STOCK OPTIONS AND WARRANTS

     At December 31, 1997, the Company had three stock-based compensation plans,
which are described below. The aggregate number of shares of Common Stock that
may be issued under these plans is 5,300,000 shares.

Stock Option Plan

     Under the Company's amended 1981 Stock Option Plan (the "Option Plan"),
qualified and non-qualified options of the Company's Common Stock may be granted
to certain employees and other individuals as determined by the Board of
Directors at not less than the fair market value of the stock at the date of
grant. Options granted under the Option Plan may be exercised when vested and
expire five years and two months to ten years from the date of grant or three
months from the date of termination of employment. Options granted generally
vest over five years. The Option Plan will terminate on November 15, 2001. As of
December 31, 1997, options covering 3,132,386 shares of Common Stock were
outstanding under the Option Plan.

Restricted Stock Plan

     The Company also has a Restricted Stock Plan (the "Restricted Plan") which
provides for the issuance of options or the direct sale of Common Stock to
certain employees and other individuals as determined by the Board of Directors
at not less than 85% of fair market value of the Common Stock on the grant date.
Each option issued under the Restricted Plan will be a non-statutory option
under the federal tax laws and will have a term not in excess of ten years from
the grant date. Options granted generally vest over five years. The Restricted
Plan will terminate on December 15, 2003.



                                       33
<PAGE>

     The Company has granted options with exercise prices at 85% of fair market
value on the date of grant. Up to 1,200,000 shares are authorized for issuance
under the Restricted Plan. As of December 31, 1997, options covering 537,479
shares of Common Stock were outstanding under the Restricted Plan.

     The Company amortizes deferred compensation, which is the difference
between the issuance price or exercise price and the fair market value of the
shares as determined by the Board of Directors at the date of sale or grant over
the period benefited.

Directors Stock Option Plan

     In 1992, the stockholders approved a Directors Stock Option Plan (the
"Directors Plan") which provides for the issuance of options to purchase shares
of Common Stock to non-employee directors of the Company at 100% of the fair
market value of the stock on the date of the grant. Up to 150,000 shares are
authorized for issuance during the term of the Directors Plan. Options vest on
the date of grant and have a term of up to ten years. As of December 31, 1997,
options for 50,000 shares of Common Stock were outstanding under the Directors
Plan.

     The Company applies APB Opinion 25 and related interpretations in
accounting for its plans. Accordingly, the financial statements reflect
amortization of compensation resulting from options granted at exercise prices
which were below market price at the grant date. Had compensation cost for the
Company's stock-based compensation plans been based on the fair value at the
grant dates for awards under these plans consistent with the provisions of FASB
Statement 123, the Company's net loss and loss per share would have been
increased to the pro forma amounts indicated below for the years ended December
31 (in thousands except per share amounts):
<TABLE>
<CAPTION>

                                                     1997                   1996                    1995
                                                     ----                   ----                    ----
<S>                       <C>                     <C>                      <C>                    <C>

Net loss                  As reported             $(15,765)                $(29,110)              $(22,472)
                          Pro forma               $(17,639)                $(30,213)              $(23,953)

Net loss per share        As reported              $  (0.44)               $  (0.90)              $  (0.97)
                          Pro forma                $  (0.48)               $  (0.94)              $  (1.04)
</TABLE>

     The fair value of each option grant under these plans is estimated on the
date of grant using the Black-Scholes option-pricing model with the following
weighted-average assumptions used for grants during the years indicated below:

                                 1997            1996           1995
                                 ----            ----           ----
Dividend yield                    0%              0%             0%
Expected volatility              71%              73%            73%
Risk-free interest rate          6.3%            5.2%           7.6%
Expected life                  7 years          7 years        6 years





                                       34
<PAGE>

     A summary of the status of the Company's stock option plans as of December
31, 1997, 1996, and 1995, and changes during years ending on those dates is
presented below:

<TABLE>
<CAPTION>
                                      1997                        1996                          1995
                                      ----                        ----                          ----
OPTIONS:                       Shares        Price*      Shares**       Price*        Shares         Price*
                               ------        ------      --------       ------        ------         ------
<S>                           <C>           <C>         <C>           <C>           <C>          <C>

Outstanding at
   beginning of year          3,196,150     $ 4.50      2,847,017     $  4.50        3,000,692   $   10.33
Granted
              (1)                 1,750       5.36          2,500        4.84           34,000        2.29
              (2)               671,000       6.68        499,750        4.97        2,204,605        2.53
              (3)                    --        --         145,333        5.00            1,250        2.94
Exercised                       (52,422)      2.72        (67,132)       2.68           (5,315)       2.40
Forfeited, Expired
   or Canceled                  (96,613)      4.33       (231,318)       6.40       (2,388,215)       9.97
                              ---------                 ---------                   ----------
Outstanding at end
   of year                    3,719,865       4.92      3,196,150        4.50        2,847,017        4.50
                              =========                 =========                    =========
Exercisable at end
   of year                    2,317,321                 1,816,185                    1,310,938
                              =========                 =========                    =========
Weighted average
   fair value of
   options granted
              (1)                             3.89                       2.71                         1.92
              (2)                             4.78                       3.09                         1.51
              (3)                              --                        1.59                         0.99

</TABLE>

*    Weighted-average exercise price
**   Includes cancellation and granting of 1,820,385 new options 
(1)  Option price less than market price on date of grant
(2)  Option price equal to market price on date of grant
(3)  Option price greater than market price on date of grant


The Company adjusts for forfeitures as they occur.

     The following table summarizes information about stock options outstanding
at December 31, 1997:
<TABLE>
<CAPTION>

                                          Options Outstanding                        Options Exercisable
         Range of                Number                                           Number
         --------                ------                                           ------
     Exercise Prices           Outstanding        Life*         Price**         Exercisable         Price**
     ---------------           -----------        ----          -----           -----------         -----
     <S>                       <C>                <C>         <C>               <C>                <C>

     $ 1.70 - 2.38                329,646          7.1         $ 2.36              184,472         $  2.36
       2.55 - 3.81              1,561,058          7.0           2.57            1,193,839            2.57
       4.06 - 5.94                620,413          6.6           4.79              281,273            4.80
       6.06 - 7.50                976,083          5.9           7.09              472,739            7.38
       7.56 -13.25                 75,700          7.9           8.92               28,033           10.98
      16.36 - 22.75               154,965          2.8          18.68              154,965           18.68
      26.50 - 26.50                 2,000          3.3          26.50                2,000           26.50
     --------------             ---------          ---         ------            ---------         -------

     $ 1.70 - 26.50             3,719,865          6.5         $ 4.92            2,317,321          $ 5.01
</TABLE>

*    Weighted-average Remaining Contractual Life
**   Weighted-average Exercise Price



                                       35
<PAGE>

Warrants

     Warrants to purchase 486,000 shares of Common Stock were issued in
conjunction with the issuance of the Series G Preferred in August 1997, all of
which expire in August 2000, at an exercise price of $10.00 per share. These
warrants were valued at $1.1 million in paid-in capital.

     The Company issued warrants valued at $0.8 million in Paid-in capital to
purchase 109,739 shares of Common Stock in conjunction with the issuance of the
Series F Preferred, one-half of which expire on March 24, 1998 and the remainder
expiring on September 24, 1999, at an exercise price of $7.29 per share.

     Warrants to purchase 1,810,980 shares of Common Stock issued in conjunction
with the issuance of the Series B Preferred Stock in December 1993 expired on
December 19, 1995. These warrants were valued at $3.0 million in paid-in
capital.

     Warrants with an aggregate value of $3.0 million at the time of issuance
were issued during the second quarter of 1993 to conclude the settlement of
certain stockholder and derivative litigation brought in 1991. A total of
2,214,633 warrants were issued, and warrants for 2,213,476 shares of Common
Stock expired unexercised in June of 1995.

6.       COMMITMENTS AND CONTINGENCIES

Clinical Trial

     Due to the termination of E5(R) development in mid-1997, the contingent
$22.4 million in future reduced royalties from Pfizer has been eliminated.

Collaborative Agreements and Royalties

     As of December 31, 1997, the Company has commitments under research
agreements with universities and other research institutions that require the
Company to fund research in the amount of $0.1 million through August 1998.
Research and development expenses include research agreement expenses of
approximately $0.2 million, $0.3 million, and $0.4 million for the years ended
December 31, 1997, 1996 and 1995, respectively. The Company is also obligated to
pay royalties, ranging generally from 1.5% to 5% of the selling price of the
licensed component and up to 25% of sublicense fee income, to various
universities and other research institutions based on future sales or licensing
of products that incorporate certain products and technologies developed by
those institutions.

Leases

     As of December 31, 1997, the Company leased administrative, research
facilities, certain laboratory and office equipment under operating and capital
leases expiring on various dates through 2008.





                                       36
<PAGE>

         Future minimum lease commitments are as follows (in thousands):

                                              Capital Leases   Operating Leases

1998                                               $ 753            $ 2,427
1999                                                  --              2,413
2000                                                  --              2,439
2001                                                  --              2,239
2002                                                  --              2,239
Thereafter                                            --             12,378
                                                   -----            -------
Net minimum lease payments                           753            $24,135
                                                                    =======
Less--Amount representing interest expense            46
                                                   -----
Present value of net minimum lease payments          707
Less--Current maturities                             707
                                                   -----
Long-term capital lease obligations                $  --
                                                   =====

     Total rental expense was approximately $2.0 million, $2.0 million, and $2.3
million for the years ended December 31, 1997, 1996, and 1995, respectively.

Legal Proceedings

     In the securities class action lawsuit Warshaw, et al. v. XOMA Corporation,
et al., the defendants and plaintiffs reached an agreement on March 14, 1997 to
settle all claims for $3.75 million in cash and $2.25 million in Common Stock.
By order entered September 8, 1997, the United States District Court for the
Northern District of California approved the settlement. All of the cash portion
of the settlement has been paid by insurance into a settlement fund administered
by an escrow agent. The claims administration process was deemed complete as of
December 16, 1997, and on January 7, 1998, XOMA directed its stock transfer
agent to issue and distribute to authorized claimants 344,168 shares of Common
Stock in accordance with the terms of the court-approved settlement agreement.

Liability Insurance

     The testing and marketing of medical and food additive products entails an
inherent risk of allegations of product liability. XOMA believes that its
product liability insurance levels are adequate for its clinical trial activity.
XOMA will seek to obtain additional insurance, if needed, if and when the
Company's products are commercialized; however, there can be no assurance that
adequate insurance coverage will be available or be available at acceptable
costs or that a product liability claim would not materially adversely affect
the business or financial condition of the Company.

     The Company insures and indemnifies its directors and officers against
actions brought against them as a result of their management of the Company's
operations. There can be no assurance that adequate directors and officers
insurance coverage will be available or be available at acceptable costs or that
a claim against the directors and officers would not materially adversely affect
the business or financial condition of the Company.





                                       37
<PAGE>

7.       INCOME TAXES

     The significant components of net deferred tax assets and liabilities as of
December 31, are as follows (in millions):

                                                1997                 1996

Property and equipment                       $    2.3              $   2.3
Purchased technology                              5.0                  5.7
Capitalized R&D expense                          62.8                 50.8
Accrued liabilities and other                     2.3                  1.4
Net operating loss carryforwards                 61.7                 66.8
R&D and other credit carryforwards               14.1                 13.0
Valuation allowance                            (148.2)              (140.0)
                                              -------              -------
Total deferred tax asset                      $    --              $    --
                                              =======              =======

     The net change in the valuation allowance was a $8.2 million and a $13.1
million increase for the years ended December 31, 1997 and 1996, respectively.

     XOMA's accumulated federal and state tax net operating losses ("NOLs") and
credits as of December 31, 1997 are as follows: 

                                       Amounts                Expiration
                                    (in millions)               Dates
Federal
   NOLs                               $ 186.4                 2001-2013
   Credits                               10.3                 1998-2013

State
   NOLs                                  26.5                 1998-2003
   Credits                                3.8                 2005-2013

     For the year ended December 31, 1997 the Company had taxable income of
$12.5 million and $11.1 million for Federal income tax and State tax,
respectively. Except for the impact of Federal alternative minimum tax, which
was not material, these taxable income amounts were offset by NOL and tax credit
carryforwards. These amounts are subject to audit by federal and state tax
authorities and could change.

     Certain future changes in the ownership of significant shareholders could
limit utilization of the Company's tax NOLs and credits.

8.       RELATED PARTY TRANSACTIONS

     In 1993, the Company granted a short-term, secured loan to an officer,
director and stockholder of the Company.

9.       DEFERRED SAVINGS PLAN

     Under section 401(k) of the Internal Revenue Code of 1986, the Board of
Directors adopted, effective June 1, 1987, a tax-qualified deferred compensation
plan for employees of the Company. Participants may make contributions which
defer up to 14% of their total salary, up to a maximum for 1997 of $9,500. The
Company may, at its sole discretion, make contributions each plan year, in cash
or in shares of the Company's Common Stock in amounts which match up to 50% of
the salary deferred by the participants. The expense of these contributions was
$233,000, $243,000, and $326,000, for the years ended December 31, 1997, 1996
and 1995, respectively.




                                       38
<PAGE>

                                INDEX TO EXHIBITS

Exhibit
Number

3.1     Restated Certificate of Incorporation, as amended.

3.1A    Certificate of Amendment of Restated Certificate of Incorporation
        (Exhibit 4.2).1

3.2     Amended and Restated Bylaws.

3.3     Stockholder Rights Agreement dated October 27, 1993 between the Company
        and First Interstate Bank of California, as Rights Agent, including
        Certificate of Designation of Preferences and Rights of Series A
        Cumulative Preferred Stock (Exhibit 1).2

3.4     Certificate of Designation of Preferences and Rights of Senior
        Convertible Preferred Stock, Series B.

3.5     Certificate of Designation of Preferences and Rights of Convertible
        Preferred Stock, Series C (Exhibit 3.4).3

3.6     Certificate of Designations of Non-Voting Cumulative Convertible
        Preferred Stock, Series D (Exhibit 4.4).4

3.7     Certificate of Designation of Convertible Preferred Stock, Series E
        (Exhibit 4.5).4

3.8     Amended Certificate of Designation of Convertible Preferred Stock,
        Series E (Exhibit 4.7).1

3.9     Certificate of Designations of Non-Voting Cumulative Convertible
        Preferred Stock, Series F (Exhibit 4.8).1

3.10    Form of Common Stock Purchase Warrant issued in connection with offering
        of Series F Preferred Stock (Exhibit 4.9).1

3.11    Certificate of Designation of Convertible Preferred Stock, Series G
        (Exhibit 2).5

3.12    Form of Common Stock Purchase Warrant issued in connection with offering
        of Series G Preferred Stock (Exhibit 3).5

10.1    1981 Stock Option Plan as amended and restated.

10.1A   Form of Stock Option Agreement for 1981 Stock Option Plan.

10.2    Restricted Stock Plan as amended and restated.

10.2A   Form of Stock Option Agreement for Restricted Stock Plan.

10.2B   Form of Restricted Stock Purchase Agreement for Restricted Stock Plan.

10.3    1985 Non-Qualified Stock Option Plan and form of Stock Option Agreement.

10.3A   Form of Assumption Agreement for 1985 Non-Qualified Stock Option Plan.



                                       39
<PAGE>

10.3B   Amendment to 1985 Non-Qualified Stock Option Plan.

10.4    1992 Directors Stock Option Plan as amended and restated.

10.4A   Form of Stock Option Agreement for 1992 Directors Stock Option Plan
        (initial grants).

10.4B   Form of Stock Option Agreement for 1992 Directors Stock Option Plan
        (subsequent grants).

10.5    Management Incentive Compensation Plan.

10.6    Form of indemnification agreement for officers.

10.7    Form of indemnification agreement for employee directors.

10.8    Form of indemnification agreement for non-employee directors.

10.9    Employment Agreement dated April 29, 1992 between the Company and John
        L. Castello.

10.10   Employment Agreement dated April 1, 1994 between the Company and Peter
        B. Davis (Exhibit 10.47).6

10.11   Employment Agreement dated March 29, 1997 between the Company and
        Patrick J. Scannon, M.D., Ph.D.

10.12   Lease of premises at 890 Heinz Street, Berkeley, California dated as of
        July 22, 1987.

10.13   Lease of premises at Building E at Aquatic Park Center, Berkeley,
        California dated as of July 22, 1987 and amendment thereto dated as of
        April 21, 1988.

10.14   Lease of premises at Building C at Aquatic Park Center, Berkeley,
        California dated as of July 22, 1987 and amendment thereto dated as of
        August 26, 1987.

10.15   Letter of Agreement regarding CPI adjustment dates for leases of
        premises at Buildings C, E and F at Aquatic Park Center, Berkeley,
        California dated as of July 22, 1987.

10.16   Lease of premises at 2910 Seventh Street, Berkeley, California dated
        March 25, 1992.

10.17   Lease dated June 22, 1992, between the Company and Richard B. Gomez,
        Josephine L. Gomez, TTEE-U/A/D, 10,31-90, FBO Gomez Family Trust.

10.18   Sublease dated January 20, 1997, between the Company and UroGenesys,
        Inc.

10.19   Lease dated October 2, 1992, between the Company and Virginia Merritt,
        as Trustee of the Bowman Merritt and Virginia Merritt Trust.

10.19A  First Extension of Lease dated April 23, 1997, between the Company and
        Virginia Merritt and Kim Merritt Campot, as Trustees of the Bowman
        Merritt and Virginia Merritt 1987 Trust.

10.20   License Agreement dated September 3, 1986 between the Company and the
        Regents of the University of California (with certain confidential
        information deleted).



                                       40
<PAGE>

10.21   Research, Development and Option Agreement, License Agreement, Supply
        Agreement, and Security Agreement all dated as of June 9, 1987 between
        the Company and Pfizer, Inc. (with certain confidential information
        deleted).

10.22   Manufacturing Agreement dated as of January 1, 1991 between the Company
        and Pfizer, Inc.

10.23   Letter Agreement dated July 14, 1993 between the Company and Pfizer,
        Inc. (with certain confidential information deleted) (Exhibit 10.41).7

10.24   Letter Agreement dated November 7, 1995 between the Company and Pfizer,
        Inc. (with certain confidential information deleted) (Exhibit 10.48).3

10.25   Settlement Agreement for Litigation with Centocor dated July 28, 1992
        (with certain confidential information deleted).

10.26   Supply Agreement effective February 27, 1989 between the Company and
        Charles River Biotechnical Services, Inc. (with certain confidential
        information deleted).

10.26A  Amendment Agreement dated as of October 17, 1991 between the Company and
        Charles River Laboratories, Inc. (with certain confidential information
        deleted).

10.27   License Agreement dated as of August 31, 1988 between the Company and
        Sanofi (with certain confidential information deleted).

10.28   Amended and Restated Research and License Agreement dated September 1,
        1993 between the Company and New York University (with certain
        confidential information omitted, which omitted information is the
        subject of a confidential treatment request and has been filed
        separately with the Securities and Exchange Commission).

10.28A  Third Amendment to License Agreement dated June 12, 1997 between the
        Company and New York University (with certain confidential information
        omitted, which omitted information is the subject of a confidential
        treatment request and has been filed separately with the Securities and
        Exchange Commission).

10.29   Cross License Agreement dated December 15, 1993 between Research
        Development Foundation and the Company (with certain confidential
        information deleted) (Exhibit 10.42).7

10.30   Cross License Agreement dated December 15, 1993 between the Company and
        Research Development Foundation (with certain confidential information
        deleted) (Exhibit 10.43).7

10.31   Technology Acquisition Agreement dated June 3, 1994 between Connective
        Therapeutics, Inc. (now called Connetics Corporation) and the Company
        (with certain confidential information deleted) (Exhibit 10.46).6

10.32   Collaboration Agreement, dated as of April 22, 1996, between the Company
        and Genentech, Inc. (with certain confidential information omitted,
        which omitted information is the subject of a confidential treatment
        request and has been filed separately with the Securities and Exchange
        Commission (Exhibit 10.1).1

10.33   Common Stock and Convertible Note Purchase Agreement, dated as of April
        22, 1996, between the Company and Genentech, Inc. (with certain
        confidential information omitted, which omitted information is the
        subject of a confidential treatment request and has been filed
        separately with the Securities and Exchange Commission) (Exhibit 10.2).1

10.33   Convertible Subordinated Note Agreement, dated as of April 22, 1996,
        between the Company and Genentech, Inc. (with certain confidential
        information omitted, which omitted 



                                       41
<PAGE>

          information is the subject of a confidential treatment request and has
          been filed separately with the Securities and Exchange Commission)
          (Exhibit 10.3).1

10.33A  Amendment to Convertible Subordinated Note Agreement, dated as of June
        13, 1996, between the Company and Genentech, Inc. (with certain
        confidential information omitted, which omitted information is the
        subject of a confidential treatment request and has been filed
        separately with the Securities and Exchange Commission) (Exhibit 10.4).1

10.34   Form of Preferred Stock Subscription Agreement by and between the
        Company and the purchasers of Series F Preferred Stock (Exhibit 10.5).1

10.35   Form of Registration Rights Agreement by and between the Company and the
        purchasers of Series F Preferred Stock (Exhibit 10.6).1

10.36   Form of Convertible Preferred Stock Purchase Agreement by and between
        the Company and the purchasers of Series G Preferred Stock (Exhibit 4).5

10.37   Form of Registration Rights Agreement by and between the Company and the
        purchasers of Series G. Preferred Stock (Exhibit 5).5

10.38   Patent and Exclusive License Purchase Agreement by and between
        Pharmaceutical Partners, L.L.C. and the Company dated as of December 30,
        1997 (Exhibit 2).8

16.1    Letter re: change of certifying accountant.9

23.1    Consent of Independent Public Accountants.

27.1    Financial Data Schedule.

- -------------------------

Footnotes

1    Incorporated by reference to the referenced exhibit to the Company's
     Registration Statement on Form S-3 filed June 28, 1996 (File No.
     333-07263).

2    Incorporated by reference to the referenced exhibit to the Company's
     Current Report on Form 8-K dated October 27, 1993 (File No. 0-14710).

3    Incorporated by reference to the referenced exhibit to the Company's Annual
     Report on Form 10-K for the fiscal year ended December 31, 1995 (File No.
     0-14710).

4    Incorporated by reference to the referenced exhibit to the Company's
     Registration Statement on Form S-3 filed April 12, 1996 (File 333-02493).

5    Incorporated by reference to the referenced exhibit to the Company's
     Current Report on Form 8-K dated August 13, 1997 (File No. 0-14710).



                                       42
<PAGE>

6    Incorporated by reference to the referenced exhibit to the Company's Annual
     Report on Form 10-K for the fiscal year ended December 31, 1994 (File No.
     0-14710).

7    Incorporated by reference to the referenced exhibit to the Company's Annual
     Report on Form 10-K for the fiscal year ended December 31, 1993 (File No.
     0-14710).

8    Incorporated by reference to the referenced exhibit to the Company's
     Current Report on Form 8-K dated December 30, 1997 (File No. 0-14710).

9    To be filed by amendment.





                                       43




                                    RESTATED
                          CERTIFICATE OF INCORPORATION
                               OF XOMA CORPORATION

         Xoma Corporation, a corporation organized and existing under the laws
of the State of Delaware, hereby certifies as follows:

         1. The name of the corporation is XOMA CORPORATION. This name was
adopted on May 14, 1981. Previously the Corporation had been called Zoma
corporation. The original Certificate of Incorporation of the Corporation was
filed with the Secretary of State of Delaware on February 24, 1981.

         2. This Restated Certificate of Incorporation ("Certificate") was duly
adopted by the Board of directors of the Corporation on December 18, 1986, and
approved by the stockholders of the Corporation at the Corporation's Annual
Meeting of Stockholders on May 13, 1987 in accordance with the provisions of
Sections 242 and 245 of the General Corporation Law of the State of Delaware.
The text of the Certificate of Incorporation as amended and restated shall be
read in full as follows:

                                       I.
                                      NAME

     The name of the Corporation is XOMA CORPORATION.

                                       II.
                                     ADDRESS

     The address of its registered office in the State of Delaware is 1209
Orange Street, in the City of Wilmington, County of New Castle. The name of its
registered agent at such address is The Corporation Trust Company.

                                      III.
                                    BUSINESS

     The nature of the business or purposes to be conducted or promoted is to
engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware. The Corporation is to have
perpetual existence.

                                       IV.
                                 STOCK STRUCTURE

     The Corporation shall be authorized to issue two classes of stock to be
designated, respectively, "preferred stock" and "common stock": the total number
of shares of both classes of stock authorized to be issued by the Corporation
shall be Twenty-One Million (21,000,000) shares. Such shares shall have no
preemptive or preferential rights of subscription concerning further issuance or
authorization of any of the Corporation's shares.

     A. Common Stock

     The total number of shares of common stock authorized to be issued by the
corporation shall be Twenty million (10,000,000) shares and each such share of
common stock shall have a par value of $.0005. The common stock may be issued
from time to time in one or more series.

                                       A-1
<PAGE>
B.  Preferred Stock

     The total number of shares of preferred stock authorized to be issued by
the corporation shall be One Million (1,000,000) shares and each such share of
preferred stock shall have a par value of $.05. The number of authorized shares
of preferred stock may be increased or decreased (but not below the number of
shares thereof then outstanding) by the affirmative vote of the holders of a
majority of the shares of preferred stock and common stock then outstanding,
voting as a single class.

                                       V.
                       RIGHTS, PREFERENCES, PRIVILEGES AND
                         RESTRICTIONS OF PREFERRED STOCK

     The preferred stock may be issued from time to time in one or more series
consisting of such number of shares (which number may be increased or decreased,
but not below the number of shares thereof then outstanding) and with such
distinctive serial designations as shall be stated and expressed in the
resolution or resolutions creating such series adopted by the Board of
Directors; and such series (a) may have such voting powers, full or limited, or
may be without voting powers; (b) may be redeemable for cash, property or
rights, and with such adjustment; (c) may be entitled to receive dividends
(which may be cumulative or non-cumulative) at such rate or rates, on such
conditions, and at such times, and payable in preference and priority to the
common stock and on a par with, or in such relation to, the dividends payable on
any other class or classes or series of stock (but not in preference or priority
to the preferred stock); (d) may have such rights upon the dissolution of, or
upon any distribution of the assets of, the corporation, including the right to
receive such distribution in preference to the common stock, and on a par with,
or in such relation to, the distribution to any other class or classes or series
of stock (but not in preference or priority to the preferred stock);(e) may be
made convertible into, or exchangeable for, at the option of either the holder
or the Corporation or upon the happening of a specified event, shares or any
other class or classes or any other series or the same or any other class or
classes of stock of the corporation, at such price or prices or at such rate or
rates of exchange, and with such adjustment; and (f) may have such other powers,
preferences and relative, participating, optional or special rights and
qualifications, limitations or restrictions thereof, all as shall hereafter be
stated and expressed in the resolution or resolutions providing for the creation
of each such series of preferred stock from time to time adopted by the Board of
directors pursuant to authority so to do which is hereby expressly vested in the
Board of Directors.

                                       VI.
                        LIMITATION ON DIRECTOR LIABILITY

     A Director of this Corporation shall not be personally liable to this
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability (i) for any breach of the director's
duty of loyalty to this corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the Director derived any improper
personal benefit. If the Delaware General Corporation law is hereafter amended
to authorize, with the approval of a corporation's stockholders, further
reductions in the liability of the corporation's directors for breach of
fiduciary duty, then a Director of this Corporation shall not be liable for any
such breach to the fullest extent permitted by the Delaware General Corporation
Law as so amended. Any repeal or modification of the foregoing provisions of
this Article Sixth by the stockholders of this Corporation shall not adversely
affect any right or protection of a Director of this Corporation existing at the
time of such repeal or modification.

                                       A-2
<PAGE>
                                      VII.
                                     BYLAWS

     In furtherance and not in limitation of the powers conferred by statute,
the Board of Directors is expressly authorized to make, alter, or repeal the
bylaws of the Corporation.

     Elections of directors need not be by written ballot unless the bylaws of
the Corporation shall so provide.

     Meetings of stockholders may be held within or without the State of
Delaware, as the bylaws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the bylaws of the Corporation.

                                      VIII.
                    AMENDMENT OF CERTIFICATE OF INCORPORATION

     Subject to the provision of Section 242 of the General Corporation Law of
the State of Delaware, The Corporation reserves the right to amend, alter,
change, or repeal any provision contained in this Certificate in the manner now
or hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.

     IN WITNESS WHEREOF, XOMA CORPORATION has caused its corporate seal to be
hereunto affixed and this Certificate to be signed by Steven C. Mendell, its
Chairman of the Board of Directors and Chief Executive officer, and attested by
David G. Koncelik, its Secretary, this 7 day of April, 1988.

                                        XOMA CORPORATION

                                        By /s/ Steven C. Mendell
                                        Steven C. Mendell
                                        Chairman of the Board of
                                        Directors and Chief
                                        Executive Officer

(SEAL)
Attest: /s/ David G. Koncelik
David C. Koncelik, Secretary

                                       A-3


<PAGE>


                       CERTIFICATE OF OWNERSHIP AND MERGER
                                     MERGING
                     INTERNATIONAL GENETIC ENGINEERING, INC.
                                      INTO
                                XOMA CORPORATION

     XOMA CORPORATION, a corporation organized and existing under the laws of
the State of Delaware,

     DOES HEREBY CERTIFY:

     FIRST: That this corporation was incorporated on the 24th day of February,
1981, pursuant to the General Corporation Law of the State of Delaware.

     SECOND: That this corporation owns all of the outstanding shares of the
stock of International Genetic Engineering, Inc., a corporation incorporated on
the 17th day of December, 1980,pursuant to the General Corporation Law of the
State of California.

     THIRD: That this corporation, by the following resolutions of its Board of
Directors, duly adopted by the unanimous written consent of its members, filed
with the minutes of the Board of Directors, determined to and did merge into
itself said International Genetic Engineering, Inc.:

          RESOLVED, that XOMA Corporation merge Inter national Genetic
     Engineering, Inc. into itself, and assume all of its obligations; and

          FURTHER RESOLVED, that the merger shall be effective upon the date of
     filing with the Secretary of State of Delaware; and
<PAGE>

          RESOLVED FURTHER, that the proper officers of the corporation be and
     they hereby are directed to make and execute a Certificate of Ownership and
     Merger setting forth a copy of the resolutions to merge International
     Genetic Engineering, Inc. and assume its liabilities and obligations, and
     the date of adoption thereof, and to cause the same to be filed with the
     Secretary of State and a certified copy recorded in the office of the
     Recorder of Deeds of new Castle County and to do all acts and things
     whatsoever, whether within or without the State of Delaware, which may be
     in any way necessary or proper to effect said merger.

     FOURTH: Anything herein or elsewhere to the contrary notwithstanding this
merger may be amended or terminated and abandoned by the board of directors of
XOMA Corporation at any time prior to the date of filing the merger with the
Secretary of State.

     IN WITNESS WHEREOF, XOMA Corporation has caused this certificate to be
signed by Steven C. Mendell, its Chairman of the Board and chief Executive
officer, and attested by Martin H. Goldstein, its vice President, General
Counsel and Secretary, this 15th day of May, 1990.

                                      XOMA CORPORATION

                                      By /s/ Steven C. Mendell
                                      Steven C. Mendell,
                                      Chairman of the Board and
                                      Chief Executive Officer

ATTEST:
By /s/ Martin H. Goldstein
         Martin H. Goldstein
         Vice President, General
         Counsel and Secretary






<PAGE>

STATE OF DELAWARE
SECRETARY OF STATE
DIVISION OF CORPORATIONS
FILES 04:30 PM 02/22/191
731053049 - 908874

BK 1122 PG 0111

                           CERTIFICATE OF AMENDMENT OF
                    RESTATED CERTIFICATE OF INCORPORATION OF
                                XOMA CORPORATION

     XOMA Corporation, a corporation organized and existing under and by virtue
of the General Corporation Law of the State of Delaware (the "Corporation"),
does hereby certify:

     FIRST: That the Board of Directors of the Corporation, at a meeting duly
held, adopted the following resolution:

     RESOLVED: that this Board deems it advisable to amend, and hereby does
amend, Article IV of the Corporation's Restated Certificate of Incorporation to
read in its entirety as follows:

                                       IV
                                 STOCK STRUCTURE

         The Corporation shall be authorized to issue two classes of stock to be
         designated, respectively, "preferred stock" and "common stock"; the
         total number of shares of both classes of stock authorized to be issued
         by the Corporation shall have no preemptive or preferential rights of
         subscription concerning further issuance or authorization of any of the
         Corporation's shares.

         A.  Common Stock.

         The total number of shares of common stock authorized to be issued by
         the Corporation shall be Forty Million (40,000,000) shares and each
         such share of common stock shall have a par value of $.0005. The common
         stock may be issued from time to time in one or more series.

         B.  Preferred Stock.

         The total number of shares of preferred stock authorized to be issued
         by the Corporation shall be One Million (1,000,000) shares and

                                      - 1 -
<PAGE>
BK 1122 PG 0112

         each such share of preferred stock shall have a par value of $.05. The
         number of authorized shares of preferred stock may be increased or
         decreased (but not below the number of shares thereof then outstanding)
         by the affirmative vote of the holders of a majority of the shares of
         preferred stock and common stock then outstanding, voting as a class."

     SECOND: That said amendment has been duly adopted by the stockholders of
this Corporation at a meeting duly held in accordance with the applicable
provisions of Sections 222 and 242 of the General Corporation Law of the State
of Delaware.

     THIRD: That said amendment has been duly adopted in accordance with the
applicable provisions of Section 242 of the General Corporation Law of the State
of Delaware.

     IN WITNESS WHEREOF, XOMA Corporation has caused this Certificate of
Amendment to be signed by Steven C. Mendell, its Chairman of the Board and Chief
Executive Officer, and Martin H. Goldstein, its Secretary, on this 22nd day of
February, 1991.

                                XOMA CORPORATION

                                By /s/Steven C. Mendell
                                      Steven C. Mendell
                                      Chairman of the Board
                                      Chief Executive Officer

Attest:

/s/Martin H. Goldstein
Martin H. Goldstein, Secretary

                                      - 2 -



                                   AMENDED AND
                                    RESTATED
                                     BYLAWS
                               AS OF OCTOBER 1993
                                XOMA CORPORATION

                                    ARTICLE I
                                     OFFICES

     Section 1. The registered office shall be in the City of Wilmington, County
of New Castle, State of Delaware.

     Section 2. The corporation may also have offices at such other places both
within and without the State of Delaware as the Board of Directors may from time
to time determine or the business of the corporation may require.

                                   ARTICLE II
                            MEETINGS OF STOCKHOLDERS

         Section 1. All meetings of the stockholders, whether for the election
of directors or for any other purpose, shall be held at such time and place,
either within or without the State of Delaware, as shall be designated from time
to time by the Board of Directors and stated in the notice of the meeting or in
a duly executed waiver of notice thereof.


<PAGE>

                                      -2-

     Section 2. At annual meetings of stockholders, the stockholders shall elect
by a plurality vote a Board of Directors, and transact such other business as
may properly be brought before the meeting.

     Section 3. Written notice of the annual meeting stating the place, date and
hour of the meeting shall be given to each stockholder entitled to vote at such
meeting not less than ten (10) nor more than sixty (60) days before the date of
the meeting.

     Section 4. The officer who has charge of the stock ledger of the
corporation shall prepare and make, or cause to be prepared and made, at least
ten days before every meeting of stockholders, a complete list of the
stockholders entitled to vote at the meeting, arranged in alphabetical order,
and showing the address of each stockholder and the number of shares registered
in the name of each stockholder. Such list shall be open to the examination of
any stockholder, for any purpose germane to the meeting, during ordinary
business hours, for a period of at least ten days prior to the meeting, either
at a place within the city where the meeting is to be held, which place shall be
specified in the notice of the meeting, or, if not so specified, at the place
where the meeting is to be held. The list shall also be produced and kept at the
time

<PAGE>
                                      -3-


and place of the meeting during the whole time thereof, and may be inspected by
any stockholder who is present.

     Section 5. Special meetings of the stockholders, for any purpose or
purposes, unless otherwise prescribed by statute or by the Certificate of
Incorporation, may be held at any place, within or without the State of
Delaware, and may be called by the Chief Executive Officer and shall be called
by the Chief Executive Officer or Secretary at the request in writing of a
majority of the Board of Directors. Such request shall state the purpose or
purposes of the proposed meeting.

     Section 6. Written notice of a special meeting stating the place, date and
hour of the meeting and the purpose or purposes for which the meeting is called
shall be given not less than ten (10) nor more than sixty (60) days before the
date of the meeting, to each stockholder entitled to vote at such meeting.

     Section 7. Business transacted at any special meeting of stockholders shall
be limited to the purposes stated in the notice.

     Section 8. The holders of a majority of the stock issued and outstanding
and entitled to vote thereat, present in person or represented by proxy, shall
constitute a quorum at

<PAGE>

                                      -4-

all meetings of the stockholders for the transaction of business except as
otherwise provided by statute or by the Certificate of Incorporation. If,
however, such quorum shall not be present or represented at any meeting of the
stockholders, the stockholders entitled to vote thereat, present in person or
represented by proxy, shall have the power to adjourn the meeting from time to
time, without notice other than announcement at the meeting, until a quorum
shall be present or represented. At such adjourned meeting at which a quorum
shall be present or represented, any business may be transacted which might have
been transacted at the meeting as originally notified. If the adjournment is for
more than thirty (30) days, or if after the adjournment a new record date is
fixed for the adjourned meeting, a notice of the adjourned meeting shall be
given to each stockholder of record entitled to vote at the meeting.

     Section 9. When a quorum is present at any meeting, the vote of the holders
of a majority of the stock present in person or represented by proxy and
entitled to vote thereat shall decide any question brought before such meeting,
unless the question is one upon which by express provision of the statues or of
the Certificate of Incorporation, a different vote is required, in which case
such express provision shall govern and control the decision of such question.

<PAGE>

                                      -5-

     Section 10. Unless otherwise provided in the Certificate of Incorporation
each stockholder shall at every meeting of the stockholders be entitled to one
vote in person or by proxy for each share of the stock entitled to vote thereat
held by such stockholder, but no proxy shall be voted on after three years from
its date, unless the proxy provides for a longer period.

     Section 11. Unless otherwise provided in the Certificate of Incorporation,
any action required to be taken at any annual or special meeting of stockholders
of the corporation, or any action which may be taken at any annual or special
meeting of such stockholders, may be taken without a meeting, without prior
notice and without a vote, if a consent in writing, setting forth the action so
taken, shall be signed by the holders of outstanding stock having not less than
the minimum number of votes that would be necessary to authorize or take such
action at a meeting at which all shares entitled to vote thereon were present
and voted. Prompt notice of the taking of the corporate action without a meeting
by less than unanimous written consent shall be given to those stockholders who
have not consented in writing.

     Section 12. At each meeting of stockholders, the chairman of the meeting
shall fix and announce the date and


<PAGE>

                                      -6-


time of the opening and the closing of the polls for each matter upon which the
stockholders will vote at the meeting and shall determine the order of business
and all other matters of procedure. Except to the extent inconsistent with any
such rules and regulations as adopted by the Board of Directors, the chairman of
the meeting may establish rules to maintain order and safety and for the conduct
of the meeting. Without limiting the foregoing, he may:

     (a) restrict attendance at any time to bona fide stockholders of record and
their proxies and other persons in attendance at the invitation of the chairman;

     (b) restrict dissemination of solicitation materials and use of audio or
visual recording devices at the meeting;

     (c) establish seating arrangements;

     (d) adjourn the meeting without a vote of the stockholders, whether or not
there is a quorum present; and

     (e) make rules governing speeches and debate including time limits and
access to microphones.

     The chairman of the meeting acts in his absolute discretion and his rulings
are not subject to appeal.

<PAGE>

                                      -7-


     Section 13. The Board of Directors, either directly or through its
designees, shall, in advance of any meeting of stockholders, appoint one or more
inspectors to act at the meeting and make a written report thereof. The Board of
Directors may designate one or more persons as alternate inspectors to replace
any inspector who fails to act. If no inspector or alternate is able to act at a
meeting of stockholders, the chairman of the meeting shall appoint one or more
inspectors to act at the meeting. Each inspector, before entering upon the
discharge of his duties, shall take and sign an oath faithfully to execute the
duties of inspector with strict impartiality and according to the best of his
ability.

     The inspectors shall:

     (a) ascertain the number of shares outstanding and the voting power of
each;

     (b) determine the shares represented at a meeting and the validity of
proxies and ballots;

     (c) count all votes and ballots;

     (d) determine and retain for a reasonable period a record of the
disposition of any challenges made to any determination by the inspectors; and

<PAGE>

                                      -8-

     (e) certify their determination of the number of shares represented at the
meeting, and their count of all votes and ballots.

The inspectors may appoint or retain other persons or entities to assist them in
the performance of their duties.

     No ballot, proxies or votes, nor any revocations thereof or changes
thereto, shall be accepted by the inspectors after the closing of the polls
unless the Court of Chancery upon application by a stockholder shall determine
otherwise.

     In determining the validity and counting of proxies and ballots, the
inspectors shall be limited to an examination of the proxies, any envelopes
submitted with those proxies, any information provided in accordance with
Section 212(c)(2) of the Delaware General Corporation Law, or a comparable
provision thereof, as then in effect, ballots and the regular books and records
of the corporation, except that the inspectors may consider other reliable
information for the limited purpose of reconciling proxies and ballots submitted
by or on behalf of banks, brokers, their nominees or similar persons which
represent more votes than the holder of a proxy is authorized by the record
owner to cast or more votes than the stockholder holds of record. If the
inspectors consider other reliable information for the limited purpose permitted
herein, they at

<PAGE>

                                      -9-

the time they make their certification shall specify the precise information
considered by them including the person or persons from whom they obtained the
information, when the information was obtained, the means by which the
information was obtained and the basis for the inspectors' belief that such
information is accurate and reliable.

                                   ARTICLE III
                                    DIRECTORS

     Section 1. The number of directors which shall constitute the whole board
shall be eight (8). The directors shall be elected at the annual meeting of the
stockholders, except as provided in Section 2 of this Article, and each director
elected shall hold office until his successor is elected and qualified, unless
sooner removed. Directors need not be stockholders. Nominations for the election
of directors may be made by the Board of Directors or a committee or person
appointed by the Board of Directors or by any stockholder entitled to vote in
the election of directors generally. However, any stockholder entitled to vote
in the election of directors generally may nominate one or more persons for
election as directors at an annual meeting only pursuant to the corporation's
notice of such meeting or if written notice of such stockholder's intent to make
such nomination or

<PAGE>

                                      -10-

nominations has been received by the Secretary of the corporation not less than
sixty nor more than ninety days prior to the first anniversary of the preceding
year's annual meeting; provided, however, that in the event that the date of the
annual meeting is advanced by more than thirty days or delayed by more than
sixty days from such anniversary, notice by the stockholder to be timely must be
so received not earlier than the ninetieth day prior to such annual meeting and
not later than the close of business on the later of (1) the sixtieth day prior
to such annual meeting or (2) the tenth day following the day on which notice of
the date of the annual meeting was mailed or public disclosure thereof was made
by the corporation, whichever first occurs. Each such notice shall set forth:
(a) the name and address of the stockholder who intends to make the nomination
and of the person or persons to be nominated; (b) a representation that the
stockholder is a holder of record of stock of the corporation entitled to vote
at such meeting and intends to appear in person or by proxy at the meeting to
nominate the person or persons specified in the notice; (c) a description of all
arrangements or understandings between the stockholder and each nominee and any
other person or persons (naming such person or persons) relating to the
nomination or nominations; (d) the class and number of shares of the corporation
which are beneficially owned by such

<PAGE>

                                      -11-

stockholder and the person to be nominated as of the date of such stockholder's
notice and by any other stockholders known by such stockholder to be supporting
such nominees as of the date of such stockholder's notice; (e) such other
information regarding each nominee proposed by such stockholder as would be
required to be included in a proxy statement filed pursuant to the proxy rules
of the Securities and Exchange Commission; and (f) the consent of each nominee
to serve as a director of the corporation if so elected. No person shall be
eligible for election as a director of the Corporation unless nominated in
accordance with the procedures set forth in this Article III, Section 1. The
presiding officer of the meeting shall, if the facts warrant, determine and
declare to the meeting that a nomination was not made in accordance with the
procedures prescribed by this Article III, Section 1, and if he or she should so
determine, the defective nomination shall be disregarded.

     Section 2. Vacancies and newly created directorships resulting from any
increase in the authorized number of directors may be filled by a majority of
the directors then in office, though less than a quorum, or by a sole remaining
director, and the directors so chosen shall hold office until the next annual
election and until their successors are duly elected and shall qualify, unless
sooner removed. If there are

<PAGE>

                                      -12-

no directors in office, then an election of directors may be held in the manner
provided by statute. If, at the time of filling any vacancy or any newly created
directorship, the directors then in office shall constitute less than a majority
of the whole board (as constituted immediately prior to any such increase), the
Court of Chancery may, upon application of any stockholder or stockholders
holding at least ten percent (10%) of the total number of the shares at the time
outstanding having the right to vote for such directors, summarily order an
election to be held to fill any such vacancies or newly created directorships,
or to replace the directors chosen by the directors then in the office.

     Section 3. The business of the corporation shall be managed by or under the
direction of its Board of Directors, which may exercise all such powers of the
corporation and do all such lawful acts and things as are not by statute or by
the Certificate of Incorporation or by these Bylaws directed or required to be
exercised or done by the stockholders.

                       MEETINGS OF THE BOARD OF DIRECTORS

     Section 4. The Board of Directors of the corporation may hold meetings,
both regular and special, either within or without the State of Delaware.


<PAGE>

                                      -13-

     Section 5. The first meeting of each newly elected Board of Directors shall
be held at such time and place as shall be fixed by the vote of the stockholders
at the annual meeting and no notice of such meeting shall be necessary to the
newly elected directors in order legally to constitute the meeting, provided a
quorum shall be present. In the event of the failure of the stockholders to fix
the time or place of such first meeting of the newly elected Board of Directors,
or in the event such meeting is not held at the time and place so fixed by the
stockholders, the meeting may be held at such time and place as shall be
specified in a notice given as hereinafter provided for special meetings of the
Board of Directors, or as shall be specified in a written waiver signed by all
of the directors.

     Section 6. Regular meetings of the Board of Directors may be held without
notice at such time and at such place as shall from time to time be determined
by the Board of Directors.

     Section 7. Special meetings of the Board of Directors may be called by the
Chairman of the Board on five days' notice to each director by mail or one day's
notice to each director either personally or by telegram or telecopier
transmission; special meetings shall be called by the Chairman

<PAGE>

                                      -14-

of the Board or Secretary in like manner and on like notice on the written
request of two directors unless the Board of Directors consists of only one
director, in which case special meetings shall be called by the Chairman of the
Board or Secretary in like manner and on like notice on the written request of
the sole director.

     Section 8. At all meetings of the Board of Directors, a majority of
directors then in office shall constitute a quorum for the transaction of
business and the act of a majority of the directors present at any meeting at
which there is a quorum shall be the act of the Board of Directors, except as
may be otherwise specifically provided by statute or by the Certificate of
Incorporation. If a quorum shall not be present at any meeting of the Board of
Directors, the directors present thereat may adjourn the meeting from time to
time, without notice other than announcement at the meeting, until a quorum
shall be present.

     Section 9. Unless otherwise restricted by the certificate of Incorporation
or these Bylaws, any action required or permitted to be taken at any meeting of
the Board of Directors or of any committee thereof may be taken without a
meeting, if all members of the Board of Directors or committee thereof, as the
case may be, consent thereto in writing, and

<PAGE>

                                      -15-

the writing or writings are filed with the minutes of proceedings of the Board
of Directors or a committee thereof.

     Section 10. Unless otherwise restricted by the Certificate of Incorporation
or these Bylaws, members of the Board of Directors, or any committee designated
by the Board of Directors, may participate in a meeting of the Board of
Directors, or any committee, by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other, and such participation in a meeting shall
constitute presence in person at the meeting.

                             COMMITTEES OF DIRECTORS

     Section 11. The Board of Directors may, by resolution passed by a majority
of the whole Board, designate one or more committees, each committee to consist
of one or more of the directors of the corporation. The Board of Directors may
designate one or more directors as alternate members of any committee, who may
replace any absent or disqualified member at any meetings of the committee.

     In the absence or disqualification of a member of a committee, the member
or members thereof present at any meeting and not disqualified from voting,
whether or not he or they

<PAGE>

                                      -16-

constitute a quorum, may unanimously appoint another member of the Board of
Directors to act at the meeting in the place of any such absent or disqualified
member.

     Any such committee, to the extent provided in the resolution of the Board
of Directors, shall have and may exercise all the powers and authority of the
Board of Directors in the management of the business and affairs of the
corporation, and may authorize the seal of the corporation to be affixed to all
papers which may require it; but no such committee shall have the power or
authority in reference to: amending the Certificate of Incorporation (except
that a committee may, to the extent authorized in the resolution or resolutions
providing for the issuance of shares of stock adopted by the Board of Directors
as provided in subsection (a) of Section 151 of the Delaware General Corporation
Law, or a comparable provision, as then in effect, fix the designations and any
of the preferences or rights of such shares relating to dividends, redemption,
dissolution, any distribution of assets of the corporation or the conversion
into, or the exchange of such shares for, shares of any other class or classes
or any other series of the same or any other class or classes of stock of the
corporation or fix the number of shares of any series of stock or authorize the
increase or decrease of the shares of any series); adopting an agreement of
merger or consolidation

<PAGE>

                                      -17-

under Section 251 or 252 of the Delaware General Corporation Law, or comparable
provisions thereof, as then in effect; recommending to the stockholders the
sale, lease or exchange of all or substantially all of the corporation's
property and assets; recommending to the stockholders a dissolution of the
corporation or a revocation of a dissolution; or amending these Bylaws of the
corporation; and, unless the resolution or the Certificate of Incorporation
expressly so provides, no such committee shall have the power or authority to
declare a dividend, to authorize the issuance of stock or to adopt a certificate
of ownership and merger pursuant to Section 253 of the Delaware General
Corporation Law,

or a comparable provision thereof, as then in effect. Such committee or
committees shall have such name or names as may be determined from time to time
by resolution adopted by the Board of Directors.

     Section 12. There shall be a committee of the Board of Directors designated
the "Compensation Committee." The Compensation Committee shall be comprised of
one or more directors of the corporation. The Compensation Committee shall have
the authority as a committee of the Board of Directors as provided in Section 11
including, but not limited to, administering all provisions of the corporation's
Stock Option

<PAGE>

                                      -18-

Plan and Restricted Stock Plan (the "Plans"), for so long as the membership of
the Compensation Committee meet the requirements of the Plans, and issuing
capital stock necessary to perform as the "Committee" and the "Plan
Administrator" (as defined in the Plans). The Compensation Committee may
administer such other plans as determined and authorized by the Board of
Directors from time to time.

     Section 13. Each committee shall keep regular minutes of its meetings and
report the same to the Board of Directors when required.

                            COMPENSATION OF DIRECTORS

     Section 14. Unless otherwise restricted by the Certificate of Incorporation
or these Bylaws, the Board of Directors shall have the authority to fix the
compensation of directors. The directors may be paid their expenses, if any, of
attendance at each meeting of the Board of Directors and may be paid a fixed sum
for attendance at each meeting of the Board of Directors and/or a stated salary
as director. No such payment shall preclude any director from serving the
corporation in any other capacity and receiving compensation therefor. Members
of special or standing committees may be allowed like compensation for attending
committee meetings.

<PAGE>

                                      -19-

                                   ARTICLE IV
                                     NOTICES

     Section 1. Whenever, under the provisions of the statutes or of the
Certificate of Incorporation or of these Bylaws, notice is required to be given
to any director or stockholder, it shall not be construed to require personal
notice, but such notice may be given in writing, by mail, addressed to such
director or stockholder, at his address as it appears on the records of the
corporation, with postage thereon prepaid, and such notice shall be deemed to be
given at the time when the same shall be deposited in the United States mail.
Notice to directors may also be given by telegram or telecopier transmission.

     Section 2. Whenever any notice is required to be given under the provisions
of the statutes or of the Certificate of Incorporation or of these Bylaws, a
waiver thereof in writing, signed by the person or persons entitled to said
notice, whether before or after the time stated therein, shall be deemed
equivalent thereto.

     Section 3. Timely written notice of any stockholder proposal (including for
the election of directors) shall be given to the Board of Directors before any
annual meeting of

<PAGE>

                                      -20-

stockholders. To be timely, a stockholder's notice must be received not less
than sixty days nor more than ninety days prior to the first anniversary of the
preceding year's annual meeting; provided, however, that in the event that the
date of the annual meeting is advanced by more than thirty days or delayed by
more than sixty days from such anniversary, notice by the stockholder to be
timely must be so received not earlier than the ninetieth day prior to such
annual meeting and not later than the close of business on the later of (1) the
sixtieth day prior to such annual meeting or (2) the tenth day following the
date on which notice of the date of the annual meeting was mailed or public
disclosure thereof was made, whichever first occurs. Each such notice shall set
forth as to each matter the stockholder proposes to bring before the annual
meeting: (a) a brief description of the business desired to be brought before
the annual meeting and the reasons for conducting such business at the meeting,
(b) the name and address, as they appear on the corporation's books, of the
stockholder proposing such business, (c) the class, series and number of shares
of the corporation which are beneficially owned by the stockholder and (d) any
material interest of the stockholder in such business. To be properly brought
before a special meeting, business must be (i) specified in the notice of
meeting (or any supplement thereto) given by or at the

<PAGE>

                                      -21-

direction of the Board of Directors or (ii) otherwise properly brought before
the meeting by or at the direction of the Board of Directors. No business shall
be conducted at any meeting of the stockholders except in accordance with the
procedures set forth in this Article IV, Section 3. The presiding officer of the
meeting shall, if the facts warrant, determine and declare to the meeting that
business was not properly brought before the meeting and in accordance with the
provisions of this Article IV, Section 3, and if he or she should so determine,
any such business not properly brought before the meeting shall not be
transacted. Nothing herein shall be deemed to affect any right of stockholders
to request inclusion of proposals in the corporation's proxy statement pursuant
to Rule 14a-8 under the Securities Exchange At of 1934, as amended.

                                    ARTICLE V
                                    OFFICERS

     Section 1. The officers of the corporation shall be chosen by the Board of
Directors and shall be a Chief Executive Officer, a Chairman of the Board, a
President, a Secretary and a Treasurer. The Board of Directors may also choose
one or more Executive Vice Presidents, Senior Vice Presidents, Vice Presidents,
Assistant Secretaries and Assistant Treasurers. Any number of offices may be
held by the same person, unless

<PAGE>

                                      -22-

the Certificate of Incorporation or these Bylaws otherwise provide.

     Section 2. The Board of Directors at its first meeting after each annual
meeting of stockholders shall choose a Chief Executive Officer, a Chairman of
the Board, a President, a Secretary, and a Treasurer.

     Section 3. The Board of Directors may appoint such other officers and
agents as it shall deem necessary, including, but not limited to, a Chief
Operating Officer, a Chief Financial Officer and a General Counsel, all of whom
shall hold their offices for such terms and shall exercise such powers and
perform such duties as shall be determined from time to time by the Board of
Directors.

     Section 4. The salaries of all officers of the corporation shall be fixed
by the Board of Directors.

     Section 5. The officers of the corporation shall hold office until their
successors are elected and qualify. Any officer elected or appointed by the
Board of Directors may be removed at any time by the affirmative vote of a
majority of the Board of Directors. Any vacancy occurring in any office of the
corporation shall be filled by the Board of Directors.

<PAGE>

                                      -23-

                           THE CHIEF EXECUTIVE OFFICER

     Section 6. The Chief Executive Officer shall have and may exercise such
powers as are, from time to time, assigned to him by the Board of Directors and
as may be provided by law, and shall preside at all meetings of the Board of
Directors or stockholders in the event that the Chairman of the Board is absent.

     Section 7. The Chief Executive Officer may execute bonds, mortgages and
other contracts requiring a seal under the seal of the corporation, except where
required by law or these Bylaws to be otherwise signed and executed and except
where the signing and execution thereof shall be expressly delegated by the
Board of Directors to some other officer or agent of the corporation.

                            THE CHAIRMAN OF THE BOARD

     Section 8. The Chairman of the Board shall preside at all meetings of the
Board of Directors and of the stockholders. The Chairman of the Board shall have
and may exercise such powers as are, from time to time, assigned to him by the
Board of Directors and as may be provided by law.

     Section 9. The Chairman of the Board may execute bonds, mortgages and other
contracts requiring a seal under the


<PAGE>

                                      -24-

seal of the corporation, except where required by law or these Bylaws to be
otherwise signed and executed and except where the signing and execution thereof
shall be expressly delegated by the Board of Directors to some other officer or
agent of the corporation.

                        THE PRESIDENT AND VICE PRESIDENTS

     Section 10. In the absence of the Chief Executive Officer and the Chairman
of the Board, the President shall preside at all meetings of the stockholders
and the Board of Directors. In the absence of the Chairman of the Board and the
Chief Executive Officer, or in the event of their inability or refusal to act,
the President shall perform the duties of the Chairman of the Board and the
Chief Executive Officer and, when so acting, shall have all the powers of and be
subject to all the restrictions upon the Chairman of the Board and the Chief
Executive Officer. The President shall perform such other duties and have such
other powers as the Board of Directors may from time to time prescribe.

     Section 11. The President may execute bonds, mortgages and other contracts
requiring a seal under the seal of the corporation, except where required by law
or these Bylaws to be otherwise signed and executed and except where the signing
and execution thereof shall be expressly delegated by

<PAGE>

                                      -25-

the Board of Directors to some other officer or agent of the corporation.

     Section 12. In the absence of the President or in the event of his
inability or refusal to act, the Executive Vice President, if any (or in the
event there be more than one Executive Vice President, the Executive Vice
Presidents in the order designated by the Board of Directors, or in the absence
of any designation, then in the order of their election), shall perform the
duties of the President and, when so acting, shall have all the powers of and be
subject to all the restrictions upon the President. In the absence of the
President and all the Executive Vice Presidents or in the event of their
inability or refusal to act, the Senior Vice President, if any (or in the event
there be more than one Senior Vice President, the Senior Vice President in the
order designated by the Board of Directors, or in the absence of any
designation, then in the order of their election), shall perform the duties of
the President and, when so acting, shall have all the powers of and be subject
to all the restrictions upon the President. In the absence of the President, all
Executive Vice Presidents and all Senior Vice Presidents or in the event of
their inability or refusal to act, the Vice President, if any (or in the event
there be more than one Vice President, the Vice President, in the order
designated by the Board of Directors, or in absence

<PAGE>

                                      -26-

of any designation, then in order of their election), shall perform the duties
of the President and, when so acting, shall have all the powers of and be
subject to all the restrictions upon the President. The Executive Vice
Presidents, the Senior Vice Presidents and Vice Presidents shall perform such
other duties and have such other powers as the Board of Directors may from time
to time prescribe.

                      THE SECRETARY AND ASSISTANT SECRETARY

     Section 13. The Secretary shall attend all meetings of the Board of
Directors and all meetings of the stockholders and record all the proceedings of
the meetings of the corporation and of the Board of Directors in a book to be
kept for that purpose and shall perform like duties for the standing committees
when required. He shall give, or cause to be given, notice of all meetings of
the stockholders and special meetings of the Board of Directors, and shall
perform such other duties as may be prescribed by the Board of Directors or the
Chairman of the Board, under whose supervision he shall be. He shall have
custody of the corporate seal of the corporation and he, or an Assistant
Secretary, if any, shall have the authority to affix the same to any instrument
requiring it and, when so affixed, it may be attested by his signature or by the
signature of such Assistant Secretary. The Board of Directors

<PAGE>

                                      -27-

may give general authority to any other officer to affix the seal of the
corporation and to attest the affixing by his signature.

     Section 14. The Assistant Secretary, if any, or, if there be more than one,
the Assistant Secretaries in the order determined by the Board of Directors (or
if there be no such determination, then in the order of their election) shall,
in the absence of the Secretary or in the event of his inability or refusal to
act, perform the duties and exercise the powers of the Secretary and shall
perform such other duties and have such other powers as the Board of Directors
may from time to time prescribe.

                      THE TREASURER AND ASSISTANT TREASURER

     Section 15. The Treasurer shall have the custody of the corporate funds and
securities and shall keep full and accurate accounts of receipts and
disbursements in books belonging to the corporation and shall deposit all moneys
and other valuable effects in the name and to the credit of the corporation in
such depositories as may be designated by the Board of Directors.

     Section 15. He shall disburse the funds of the corporation as may be
ordered by the Board of Directors, taking


<PAGE>

                                      -28-

proper vouchers for such disbursements, and shall render to the Chairman of the
Board and the Board of Directors, at its regular meetings, or when the Board of
Directors so requires, an account of all his transactions as Treasurer and of
the financial condition of the corporation.

     Section 16. If required by the Board of Directors, he shall give the
corporation a bond (which shall be renewed every six years) in such sum and with
such surety or sureties as shall be satisfactory to the Board of Directors for
the faithful performance of the duties of his office and for the restoration to
the corporation, in case of his death, resignation, retirement or removal from
office, of all books, papers, vouchers, money and other property of whatever
kind in his possession or under his control belonging to the corporation.

     Section 17. The Assistant Treasurer, if any, or, if there shall be more
than one, the Assistant Treasurers in the order determined by the Board of
Directors (or if there be no such determination, then in the order of their
election) shall, in the absence of the Treasurer or in the event of his
inability or refusal to act, perform the duties and exercise the powers of the
Treasurer and shall perform such other duties

<PAGE>

                                      -29-

and have such other powers as the Board of Directors may from time to time
prescribe.

                                   ARTICLE VI
                              CERTIFICATES OF STOCK

     Section 1. Every holder of stock in the corporation shall be entitled to
have a certificate signed by, or in the name of the corporation by, the Chief
Executive Officer or the Chairman of the Board or the President or an Executive
Vice President, or a Senior Vice President or a Vice President, and by the
Secretary or an Assistant Secretary or the Treasurer or an Assistant Treasurer
of the corporation, certifying the number of shares owned by him in the
corporation.

     Certificates may be issued for partly paid shares and in such case upon the
face or back of the certificates issued to represent any such partly paid shares
the total amount of the consideration to be paid therefor and the amount paid
thereon shall be specified.

     If the corporation shall be authorized to issue more than one class of
stock or more than one series of any class, the powers, designations,
preferences and relative, participating, optional or other special rights of
each class of stock or series thereof and the qualifications, limitations

<PAGE>

                                      -30-

or restrictions of such preferences and/or rights shall be set forth in full or
summarized on the face or back of the certificate which the corporation shall
issue to represent such class or series of stock, provided that, except as
otherwise provided in Section 202 of the Delaware General Corporation Law, or a
comparable provision, as then in effect, in lieu of the foregoing requirements,
there may be set forth on the face or back of the certificate which the
corporation shall issue to represent such class or series of stock a statement
that the corporation will furnish without charge to each stockholder who so
requests the powers, designations, preferences and relative, participating,
optional or other special rights of each class of stock or series thereof and
the qualifications, limitations or restrictions of such preferences and/or
rights.

     Section 2. Any or all of the signatures on the certificate may be
facsimile. In case any officer, transfer agent or registrar who has signed or
whose facsimile signature has been placed upon a certificate shall have ceased
to be such officer, transfer agent or registrar before such certificate is
issued, it may be issued by the corporation with the same effect as if he were
such officer, transfer agent or registrar at the date of issue.

<PAGE>

                                      -31-

                                LOST CERTIFICATES

     Section 3. The Board of Directors, either directly or through the Secretary
as its designee, may direct a new certificate or certificates to be issued in
place of any certificate or certificates theretofore issued by the corporation
alleged to have been lost, stolen or destroyed, upon the making of an affidavit
of that fact by the person claiming the certificate of stock to be lost, stolen
or destroyed. When authorizing such issue of a new certificate or certificates,
the Board of Directors or the Secretary may, in its or his discretion and as a
condition precedent to the issuance thereof, require the owner of such lost,
stolen or destroyed certificate or certificates, or his legal representative, to
advertise the same in such manner as it or he shall require and/or to give the
corporation a bond in such sum as it or he may direct as indemnity against any
claim that may be made against the corporation with respect to the certificate
alleged to have been lost, stolen or destroyed.

                                TRANSFER OF STOCK

     Section 4. Upon surrender to the corporation or the transfer agent of the
corporation of a certificate for shares duly endorsed or accompanied by proper
evidence of succession, assignation or authority to transfer, it shall be the
duty of

<PAGE>

                                      -32-

the corporation to issue a new certificate to the person entitled thereto,
cancel the old certificate and record the transaction upon its books.

                               FIXING RECORD DATE

     Section 5. In order that the corporation may determine the stockholders
entitled to notice of or to vote at any meeting of stockholders or any
adjournment thereof, or to express consent to corporate action in writing
without a meeting, or entitled to receive payment of any dividend or other
distribution or allotment of any rights, or entitled to exercise any rights in
respect of any change, conversion or exchange of stock or for the purpose of any
other lawful action, the Board of Directors may fix, in advance, a record date,
which shall not be more than sixty nor less than ten days before the date of
such meeting, nor more than sixty days prior to any other action. A
determination of stockholders of record entitled to notice of or to vote at a
meeting of stockholders shall apply to any adjournment of the meeting provided,
however, that the Board of Directors may fix a new record date for the adjourned
meeting.

<PAGE>

                                      -33-

                             REGISTERED STOCKHOLDERS

     Section 6. The corporation shall be entitled to recognize the exclusive
right of a person registered on its books as the owner of shares to receive
dividends, and to vote as such owner, and to hold liable for calls and
assessments a person registered on its books as the owner of shares, and shall
not be bound to recognize any equitable or other claim to or interest in such
share or shares on the part of any other person, whether or not it shall have
express or other notice thereof, except as otherwise provided by the laws of
Delaware.

                                   ARTICLE VII
                               GENERAL PROVISIONS

                                    DIVIDENDS

     Section 1. Dividends upon the capital stock of the corporation, subject to
the provisions of the Certificate of Incorporation, if any, may be declared by
the Board of Directors at any regular or special meeting, pursuant to law.
Dividends may be paid in cash, in property, or in shares of capital stock,
subject to the provisions of the Certificate of Incorporation.

<PAGE>

                                      -34-

     Section 2. Before payment of any dividend, there may be set aside out of
any funds of the corporation available for dividends such sum or sums as the
directors from time to time, in their absolute discretion, think proper as a
reserve or reserves to meet contingencies, or for equalizing dividends, or for
repairing or maintaining any property of the corporation, or for such other
purpose as the directors shall think conducive to the interest of the
corporation, and the directors may modify or abolish any such reserve in the
manner in which it was created.

                                     CHECKS

     Section 3. All checks or demands for money and notes of the corporation
shall be signed by such officer or officers or such other person or persons as
the Board of Directors may from time to time designate.

                                   FISCAL YEAR

     Section 4. The fiscal year of the corporation shall be the calendar year
unless another fiscal year is fixed by resolution of the Board of Directors.


<PAGE>

                                      -35-

                                      SEAL

     Section 5. The Board of Directors may adopt a corporate seal having
inscribed thereon the name of the corporation, the year of its organization and
the words "Corporate Seal, Delaware". The seal may be used by causing it or a
facsimile thereof to be impressed or affixed or reproduced or otherwise.

                                 INDEMNIFICATION

     Section 6. The corporation shall indemnify its officers, directors and
employees to the full extent permitted by the Delaware General Corporation Law.

     Expenses (including attorneys' fees) incurred by an officer or director of
the corporation in defending any civil, criminal, administrative or
investigative action, suit or proceeding shall be paid by the corporation in
advance of the final disposition of such action, suit or proceeding upon receipt
of an undertaking by or on behalf of such director or officer to repay such
amount if it shall ultimately be determined that he is not entitled to be
indemnified by the corporation as authorized by relevant sections of the
Delaware General Corporation Law.

<PAGE>

                                      -36-

     The indemnification and advancement of expenses provided by this section
shall not be deemed exclusive of any other rights which any person may have or
hereafter acquire under any statute, provision of this corporation's Certificate
of Incorporation, Bylaw, agreement, vote of stockholders or disinterested
directors or otherwise.

                                NUMBER AND GENDER

     Section 7. Words used herein, regardless of the number and gender
specifically used, shall be deemed and construed to include any other number,
singular or plural, and any other gender, masculine, feminine or neuter, as the
context requires.

                                  SEPARABILITY

     Section 8. In case any provision of these Bylaws shall be invalid, illegal
or unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

                                  ARTICLE VIII
                                   AMENDMENTS

     Section 1. These Bylaws may be altered, amended or repealed or new Bylaws
may be adopted by the stockholders or by


<PAGE>

                                      -37-

the Board of Directors, when such power is conferred upon the Board of Directors
by the Certificate of Incorporation, at any regular meeting of the stockholders
or of the Board of Directors or at any special meeting of the stockholders or of
the Board of Directors if notice of such alteration, amendment, repeal or
adoption of new Bylaws be contained in the notice of such special meeting. If
the power to adopt, amend or repeal Bylaws is conferred upon the Board of
Directors by the Certificate of Incorporation, it shall not divest or limit the
power of the stockholders to adopt, amend or repeal Bylaws.



                          CERTIFICATE OF DESIGNATION OF
                            PREFERENCES AND RIGHTS OF
                  SENIOR CONVERTIBLE PREFERRED STOCK, SERIES B

                                       OF

                                XOMA CORPORATION

                                 --------------

                         Pursuant to Section 151 of the
                         General Corporation Law of the
                                State of Delaware

                                 --------------


     XOMA CORPORATION, a corporation organized and existing under the General
Corporation Law of the State of Delaware (the "Corporation"), does hereby
certify that, pursuant to authority conferred upon the Board of Directors by the
Amended and Restated Certificate of Incorporation, and pursuant to the
provisions of Section 151 of the Delaware General Corporation Law, said Board of
Directors duly adopted a resolution on October 27, 1993, which approved the
filing of this Certificate of Designation and which resolution remains in full
force and effect as of the date hereof.

     Pursuant to such resolution and the authority conferred upon the Board of
Directors by the Amended and Restated Certificate of Incorporation of the
Corporation, there is hereby created a series of preferred stock of the
Corporation, which series shall have the following powers, preferences, and
relative, participating, optional or other special rights, and the
qualifications, limitations or restrictions thereof, in addition to those set
forth in the Amended and Restated Certificate of Incorporation of the
Corporation:

     1. Certain Definitions. As used herein, the following terms shall have the
following meanings (with terms defined in the singular having comparable
meanings when used in the plural and vice versa), unless the context otherwise
requires:

          "Affiliate" of any specified Person means any other Person which,
     directly or indirectly, controls, is controlled by or is under direct or
     indirect common control with, such specified Person. For the purposes of
     this 


<PAGE>
                                      -2-


     definition, "control" when used with respect to any Person means beneficial
     ownership of 5.0% or more of the outstanding securities entitled to vote
     for the election of a member of the board of directors of a corporation or
     the power to direct the management and policies of such Person, directly or
     indirectly, whether through the ownership of voting securities, by contract
     or otherwise, and the terms "controlling" and "controlled" have meanings
     correlative to the foregoing.

          "Board of Directors" means the Board of Directors of the Corporation.

          "Business Day" means a day that is not a Saturday, a Sunday or a day
     on which banking institutions in the State of New York or California are
     not required to be open.

          "Cash Redemption Price" means $1,000 per share of Series B Preferred
     Stock.

          "Common Stock" means the Common Stock, par value $.0005 per share, of
     the Corporation.

          "Conversion Price" means 91.5% of the average of the per share Quoted
     Prices for the Common Stock for the twenty (20) trading days subsequent to
     November 19, 1993.

          "Convertible Securities" has the meaning specified in Section 6(C)
     hereof.

          "Corporation" means XOMA Corporation, a Delaware corporation.

          "Dividend Declaration Date" means a day preceding each Dividend
     Payment Date when the Board of Directors shall either (i) declare a
     dividend in cash or Dividend Shares or (ii) in the event no dividend is
     declared, determine whether a dividend is to accrue in cash or Dividend
     Shares.

          "Dividend Payment Date" means December 31 and June 30 of each year
     beginning June 30, 1994, unless such day is not a Business Day in which
     case the Dividend Payment Date shall be the immediately succeeding Business
     Day.

          "Dividend Record Date" means a day fifteen (15) days preceding the
     Dividend Payment Date.


<PAGE>
                                      -3-


          "Dividend Shares" has the meaning specified in Section 3(B) hereof.

          "Eligible Transferee" means a Person who is not, and who is not an
     Affiliate of, a Person who is (i) directly or indirectly, in any manner
     whatsoever engaged in or participating in, either alone or together with
     any other Person, the manufacturing, distribution, sale, research or
     development of pharmaceutical or medical products, whether diagnostic or
     therapeutic, (ii) a hospital or other provider of medical or healthcare
     services (other than a natural person who provides medical or healthcare
     services and is otherwise an Eligible Transferee), (iii) an educational or
     research institution (whether or not accredited and whether or not exempt
     from federal income taxation pursuant to section 501(c) of the Internal
     Revenue Code, as amended) or (iv) directly or indirectly, in any manner
     whatsoever engaged in or participating in, either alone or together with
     any other Person, the manufacturing, distribution, sale, research or
     development of products derived from, or as a result of, biotechnology.

          "GDK" means GDK, Inc., a corporation organized under the laws of the
     British Virgin Islands and an original purchaser of the Series B Preferred
     Stock.

          "Holder" means a registered holder of shares of Series B Preferred
     Stock.

          "Liquidation Preference" means $1,000 per share of Series B Preferred
     Stock plus accrued and unpaid dividends, if any, thereon through the date
     such Liquidation Preference is paid.

          "Options" has the meaning specified in Section 6(C) hereof.

          "Ortelius" means Ortelius Trading L.P., a Delaware limited partnership
     and an original purchaser of the Series B Preferred Stock.

          "Permitted Transfer" means the sale, assignment, conveyance, transfer,
     pledge, hypothecation or other disposition of at least 1000 shares of
     Series B Preferred Stock in a single transaction to a single Eligible
     Transferee.

          "Person" means any natural person, corporation, partnership, joint
     venture, association, joint-stock company, 


<PAGE>
                                      -4-


     trust, unincorporated organization or government or any agency or political
     subdivision thereof.

          "Quoted Price" has the meaning specified in Section 3(B) hereof.

          "Redemption Date" means, with respect to any shares of Series B
     Preferred Stock, the date fixed by the Corporation for redemption of such
     shares of Series B Preferred Stock.

          "Redemption Notice" has the meaning specified in Section 7(B) hereof.

          "Redemption Consideration" has the meaning specified in Section 7(c)
     hereof.

          "Registration Rights Agreement" means the Registration Rights
     Agreement made and entered into as of November 18, 1993 by and among the
     Corporation, Ortelius and GDK.

          "Securities Act" has the meaning specified in Section 15 hereof.

          "Series B Preferred Stock" has the meaning specified in Section 2
     hereof.

          "Series B Preferred Stock Certificate" has the meaning specified in
     Section 6 hereof.

     2. Designation. The series of preferred stock established hereby shall be
designated the "Senior Convertible Preferred Stock, Series B" (and shall be
referred to herein as the "Series B Preferred Stock") and the authorized number
of shares of Series B Preferred Stock shall be 30,000 shares.

     3. Dividends.

     (A) Holders will be entitled to receive, when, as and if declared by the
Board of Directors, out of funds legally available therefor, dividends at an
annual rate equal to $50.00 per share. Dividends will be cumulative and will
accrue from the date of issuance and be payable semi-annually in arrears on each
Dividend Payment Date, commencing on June 30, 1994. Dividends, whether or not
declared, will cumulate until declared and paid, when declaration and payment
may be for all or part of the then-accumulated dividends. Dividends will be
computed on the basis of a 360-day 


<PAGE>
                                      -5-


year comprised of twelve 30-day months. Each dividend shall be payable to
Holders of record as they appear on the stock books of the Corporation on each
Dividend Record Date. Accrued and unpaid dividends, if any, shall not bear
interest. Dividends shall cease to accrue in respect of shares of Series B
Preferred Stock on the Redemption Date.

     (B) On any Dividend Payment Date, in lieu of payment in cash, the
Corporation may, at its option, make all or any portion of any dividend payments
(including accumulated dividends) by issuing to the Holders, in the aggregate,
such number of fully paid and non-assessable shares (calculated to the nearest
1/100th of a share) of Common Stock ("Dividend Shares") as is obtained by
dividing the cash amount (or portion thereof) that would otherwise be paid on
such Dividend Payment Date by the average of the Quoted Prices for the Common
Stock for the five (5) trading days preceding the Dividend Payment Date. The
"Quoted Price" of the Common Stock at any date is (i) if the Common Stock is
listed on a securities exchange, the last reported sales price per share of the
Common Stock on the principal securities exchange, if any, on which the Common
Stock is listed that shall be for consolidated trading, if applicable to such
exchange, or (ii) if not so listed, the last reported sales price per share of
the Common Stock as reported by the NASDAQ National Market System, or (iii) if
neither so listed nor reported, the last reported bid price per share of the
Common Stock or (iv) in the absence of one or more of such quotations, the
current market price per share of the Common Stock as determined by an
independent investment banking firm chosen by the Corporation and reasonably
acceptable to the Purchasers.

     (C) On each Dividend Declaration Date, the Board of Directors shall declare
whether or not a dividend is to be paid. If a dividend is declared on such
Dividend Declaration Date, the Board of Directors shall determine whether the
dividend shall be paid in cash or Dividend Shares or a combination of cash and
Dividend Shares, and in the event the dividend is to be paid in a combination of
cash and Dividend Shares, the portion of the dividend to be so paid. If no
dividend is declared on such Dividend Declaration Date, the Board of Directors
shall determine whether the dividend shall accrue is cash or Dividend Shares or
in a combination of cash and Dividend Shares, and if the dividend is to accrue
in a combination of cash and Dividend Shares, the cash portion and Dividend
Shares portion of such accrued dividend.


<PAGE>
                                      -6-


     4. Ranking. The Series B Preferred Stock shall, with respect to dividend
rights and rights on liquidation, winding-up and dissolution, rank senior to all
classes of Com mon Stock and to any other class or series of any class of pre
ferred stock of the Corporation, whether now outstandinq or issued hereafter.

     5. Voting Rights. Except as required by the General Corporation Law of the
State of Delaware, the Holders shall not be entitled to vote on any matter
submitted to a vot of stockholders of the Corporation.

     6. Conversion. The Holder of each share of Series B Preferred Stock shall
have the right at any time, or from time to time (except as otherwise herein
provided if such share shall be called for redemption pursuant to Section 7), at
the option of such Holder, to convert such shares into Common Stock, on and
subject to the terms and conditions hereinafter set forth.

     (A) Subject to the provisions for adjustment hereinafter set forth, each
share of Series B Preferred Stock shall be convertible into such number of fully
paid and nonassessable shares (calculated as to each conversion to the nearest
1/100 of a share) of Common Stock as is obtained by dividing 1,000 by the
Conversion Price as last adjusted and in effect at the date any share or shares
of Series B Preferred Stock are surrendered for conversion.

     (B) In order to exercise the conversion privilege, the Holder of any shares
of Series B Preferred Stock to be converted in whole or in part shall surrender
the certificate representing such shares of Series B Preferred Stock (the
"Series B Preferred Stock Certificate") at the office or agency then maintained
by the Corporation for the transfer of the Series B Preferred Stock, and shall
give written notice of conversion in the form provided on the Series B Preferred
Stock Certificate (or such other notice which is acceptable to the Corporation)
to the Corporation at such office or agency that the Holder elects to convert
such shares of Series B Preferred Stock represented by the Series B Preferred
Stock Certificate so surrendered or the portion thereof specified in said
notice. Such notice shall also state the name or names (with addresses) in which
the certificate or certificates for shares of Common Stock which shall be
issuable upon such conversion shall be issued, and shall be accompanied by
transfer taxes, if required. Each 


<PAGE>
                                      -7-


Series B Preferred Stock Certificate surrendered for conversion shall, unless
the shares issuable on conversion are to be issued in the same name as the
registration of such Series B Preferred Stock Certificate, be duly endorsed by,
or be accompanied by instruments of transfer in form satisfactory to the
Corporation duly executed by, the Holder or his duly authorized attorney.

     As promptly as practicable after the surrender of such Series B Preferred
Stock Certificate and the receipt of such notice and funds, if any, as
aforesaid, the Corporation shall issue and shall deliver at such office or
agency to such Holder, or on his written order, a certificate or certificates
for the number of shares of Common Stock issuable upon the conversion of such
shares of Series B Preferred Stock represented by the Series B Preferred Stock
Certificate so surrendered or portion thereof in accordance with the provisions
of this Section 6. In case less than all of the shares of Series B Preferred
Stock represented by a Series B Preferred Stock Certificate surrendered for
conversion are to be converted, the Corporation shall deliver to or upon the
written order of the Holder of such Series B Preferred Stock Certificate a new
Series B Preferred Stock Certificate representing the shares of Series B
Preferred Stock not converted. If a Holder fails to notify the Corporation of
the number of shares of Series B Preferred Stock which such Holder wishes to
convert, such Holder shall be deemed to have elected to convert all shares
represented by the certificate or certificates surrendered for conversion.

     Each conversion shall be deemed to have been effected on the date on which
such Series B Preferred Stock Certificate shall have been surrendered and such
notice shall have been received by the Corporation, as aforesaid, and the person
in whose name any certificate or certificates for shares of Common Stock shall
be issuable upon such conversion shall be deemed to have become on said date the
holder of record of the shares represented thereby; provided, however, that any
such surrender on any date when the stock books of the Corporation shall be
closed shall constitute the person in whose name the certificates are to be
issued as the record holder thereof for all purposes on the next succeeding day
on which such stock books are open, but such conversion shall be at the
Conversion Price as last adjusted and in effect on the date upon which such
Series B Preferred Stock Certificate shall have been surrendered.

     The dividends due on any Series B Preferred Stock surrendered for
conversion during the period from the close of business on a Dividend Record
Date to the opening of business on the corresponding Dividend Payment Date shall
be paid to the


<PAGE>
                                      -8-


Holder of Series B Preferred Stock, notwithstanding such conversion.

     In the event any shares of Series B Preferred Stock shall be called for
redemption, the right to convert such shares of Series B Preferred Stock into
shares of Common Stock shall terminate at the close of business on the
Redemption Date. Notwithstanding anything to the contrary contained in this
paragraph (B), the Corporation may, at its option, be deemed to have purchased
any shares of Series B Preferred Stock that are called for redemption and not
surrendered for conversion prior to the close of business on the Redemption Date
at a purchase price equal to the price that would have been paid had such shares
been redeemed (including accrued and unpaid dividends to the date fixed for such
redemption) and immediately sell such shares to any registered broker-dealer who
has agreed to purchase such shares at a price at least equal to the price paid
by the Corporation for such shares and to convert such shares into shares of
Common Stock.

     (C) Except as provided in subparagraph (ix) hereof and in paragraph (D)
below, if and whenever the Corporation shall issue or sell or is deemed, in
accordance with subparagraphs (i) through (xi) hereof, to have issued or sold
any shares of Common Stock for a consideration per share less than the
Conversion Price of the Common Stock as of the time of issuance then, forthwith
upon such issuance or sale or deemed issuance or sale, the Conversion Price
shall be reduced to the price determined by dividing (i) an amount equal to the
sum of (a) the number of shares of Common Stock outstanding immediately prior to
such issuance or sale (including as outstanding all shares of Common Stock
issuable upon conversion of all outstanding shares of Series B Preferred Stock)
multiplied by the then existing Conversion Price, and (b) the consideration, if
any, received by the Corporation upon such issuance or sale, by (ii) the total
number of shares of Common Stock outstanding immediately after such issuance or
sale (including as outstanding all shares of Common Stock issuable upon
conversion of all outstanding shares of Series B Preferred Stock).

     For purposes of this paragraph (C), the following subparagraphs (i) to (xi)
inclusive shall be applicable:

          (i) In case at any time the Corporation shall in any manner grant
     (whether directly or by assumption in a merger or otherwise) any rights to
     subscribe for or to purchase, or any options for the 


<PAGE>
                                      -9-


     purchase of, Common Stock or any stock or securities convertible into or
     exchangeable for Common Stock (such rights or options being herein called
     "Options" and such convertible or exchangeable stock or securities being
     herein called "Convertible Securities") whether or not such Options, or the
     right to convert or exchange any such Convertible Securities are
     immediately exercisable, and the price per share for which Common Stock is
     issuable upon the exercise of such Options or upon conversion or exchange
     of such Convertible Securities (determined by dividing (x) the total
     amount, if any, received or receivable by the Corporation as consideration
     for the granting of such Options, plus the minimum aggregate amount of
     additional consideration payable to the Corporation upon the exercise of
     all such options, plus, in the case of Convertible Securities, the minimum
     aggregate amount of additional consideration, if any, payable upon the
     issue or sale of such Convertible Securities and upon the conversion or
     exchange thereof, by (y) the total maximum number of shares of Common Stock
     issuable upon the exercise of such options or upon the conversion or
     exchange of all such Convertible Securities issuable upon the exercise of
     such Options) shall be less than the Conversion Price as in effect
     immediately prior to the time of granting of such options, then the total
     maximum number of shares of Common Stock issuable upon the exercise of such
     options or upon conversion or exchange of the total maximum amount of such
     Convertible Securities issuable upon the exercise of such Options shall be
     deemed to have been issued for such price per share as of the date of
     granting of such Options and thereafter shall be deemed to be outstanding.
     Except as otherwise provided in subparagraph (iii), no adjustment of the
     Conversion Price shall be made upon the actual issue of such Common Stock
     or of such Convertible Securities upon exercise of such Options or upon the
     actual issue of such Common Stock upon conversion or exchange of such
     Convertible Securities.

          (ii) Issuance of Convertible Securities. In case the Corporation shall
     in any manner issue (whether directly or by assumption in a merger or
     otherwise) or sell any Convertible Securities, whether or not the rights to
     exchange or convert thereunder are immediately exercisable, and the 


<PAGE>
                                      -10-


     price per share for which Common Stock is issuable upon such conversion or
     exchange (determined by dividing (x) the total amount received or
     receivable by the Corporation as consideration for the issue or sale of
     such Convertible Securities, plus the minimum aggregate amount of
     additional consideration, if any, payable to the Corporation upon the
     conversion or exchange thereof, by (y) the total maximum number of shares
     of Common Stock issuable upon the conversion or exchange or all such
     Convertible Securities) shall be less than the Conversion Price as in
     effect immediately prior to the time of such issue or sale, then the total
     maximum number of shares of Common Stock issuable upon conversion or
     exchange of all such Convertible Securities shall be deemed to have been
     issued for such price per share as of the date of the issue or sale of such
     Convertible Securities and thereafter shall be deemed to be outstanding,
     provided that (a) except as otherwise provided in subparagraph (iii) below,
     no adjustment of the Conversion Price shall be made upon the actual issue
     of such Common Stock upon conversion or exchange of such Convertible
     Securities and (b) if any such issue or sale of such Convertible Securities
     is made upon exercise of any Option to purchase any such Convertible
     Securities for which adjustments of such Conversion Price have been or are
     to be made pursuant to other provisions of this paragraph (C), no further
     adjustment of such Conversion Price shall be made by reason of such issue
     or sale.

          (iii) Change in Option Price or Conversion Rate. Upon the happening of
     any of the following events, namely, if the purchase price provided for in
     any Option referred to in subparagraph (i), the additional consideration,
     if any, payable upon the conversion or exchange of any Convertible
     Securities referred to in subparagraph (i) or (ii), or the rate at which
     any Convertible Securities referred to in subparagraph (i) or (ii) are
     convertible into or exchangeable for Common Stock shall change at any time
     (other than under or by reason of provisions designed to protect against
     dilution), the Conversion Price in effect at the time of such event shall
     forthwith be readjusted to the Conversion Price which would have been in
     effect at such time had such Options or Convertible Securities still
     outstanding provided for such changed purchase price, 


<PAGE>
                                      -11-


     additional consideration or conversion rate, as the case may be, at the
     time initially granted, issued or sold; and on the expiration of any such
     Option or termination of any such right to convert or exchange such
     Convertible Securities, the Conversion Price then in effect hereunder shall
     forthwith be increased to the Conversion Price that would have been in
     effect at the time of such expiration or termination had such Option or
     Convertible Securities, to the extent outstanding immediately prior to such
     expiration or termination, never been issued, and the Common Stock issuable
     thereunder shall no longer be deemed to be outstanding.

          (iv) Stock Dividends. In case the Corporation shall declare a dividend
     or make any other distribution upon any stock of the Corporation payable in
     Common Stock, Options or Convertible Securities, any Common Stock, Options
     or Convertible Securities, as the case may be, issuable in payment of such
     dividend or distribution shall be deemed to have been issued or sold
     without consideration.

          (v) Consideration for Stock. In case any shares of Common Stock,
     Options or Convertible Securities shall be issued or sold for cash, the
     consideration received therefor shall be deemed to be the amount received
     by the Corporation therefor, without deduction therefrom of any expenses
     incurred or any underwriting commissions or concessions paid or allowed by
     the Corporation in connection therewith. In case any shares of Common
     Stock, Options or Convertible Securities shall be issued or sold for a
     consideration other than cash, the amount of the consideration other than
     cash received by the Corporation shall be deemed to be the fair value of
     such consideration as determined in good faith by the Board of Directors,
     without deduction of any expenses incurred or any underwriting commissions
     or concessions paid or allowed by the Corporation in connection therewith.
     In case any Options shall be issued in connection with the issue and sale
     of other securities of the Company, together compromising one integral
     transaction in which no specific consideration is allocated to such Options
     by the parties thereto, the consideration deemed to have been received by
     the Corporation shall be determined by the Board of Directors in good
     faith.


<PAGE>
                                      -12-


          (vi) Record Date. In case the Corporation shall take a record of the
     holders of its Common Stock for the purpose of entitling them (i) to
     receive a dividend or other distribution payable in Common Stock, Options
     or Convertible Securities, or (ii) to subscribe for or purchase Common
     Stock, Options or Convertible Securities, then such record date shall be
     deemed to be the date of the issue or sale of the shares of Common Stock
     deemed to have been issued or sold upon the declaration of such dividend or
     the making of such other distribution or the date of the granting of such
     right of subscription or purchase, as the case may be.

          (vii) Treasury Shares. The number of shares of Common Stock
     outstanding at any given time shall not include shares owned or held by or
     for the account of the Corporation, and the disposition of any such shares
     shall be considered an issue or sale of Common Stock for the purpose of
     this paragraph (C).

          (viii) Subdivision or Combination of Common Stock. In case the
     Corporation shall at any time subdivide its outstanding shares of Common
     Stock into a greater number of shares, the Conversion Price in effect
     immediately prior to such subdivision shall be proportionately reduced, and
     conversely, in case the outstanding shares of Common Stock of the
     Corporation shall be combined into a smaller number of shares, the
     Conversion Price in effect immediately prior to such combination shall be
     proportionately increased.

          (ix) Certain Issues of Common Stock Excepted. Anything herein to the
     contrary notwithstanding, the Corporation shall not be required to make any
     adjustment of the Conversion Price in the case of (i) the issuance of
     shares of Common Stock upon conversion or redemption of shares of Series B
     Preferred Stock in accordance with the terms thereof, (ii) the issuance of
     shares of Common Stock in payment of dividends upon the Series B Preferred
     Stock in accordance with the terms thereof, (iii) the issuance of up to
     three (3) million shares of Common Stock (or the issuance of options
     therefor) reserved for issuance to employees of the Corporation pursuant to
     any employee benefit or compensation plan or arrangement which amount
     includes 872,075 shares of 


<PAGE>
                                      -13-


     Common Stock which are currently issuable under existing stock option
     plans, (iv) the issuance of shares of Common Stock upon the exercise of
     warrants granted by the Corporation to Ortelius and GDK, (v) the issuance
     of shares of Common Stock upon the exercise of Warrants pursuant to the
     Warrant Agreement dated as of June 3, 1993 between the Corporation and
     First Interstate Bank of California, as Warrant Agent or (vi) the issuance
     of shares of Common Stock in connection with preferred stock purchase
     rights relating to the Corporation's Series A Cumulative Preferred Stock,
     par value $.05 per share.

          (x) Reorganization or Reclassification. If any capital reorganization
     or reclassification of the capital stock of the Corporation shall be
     effected in such a way (including, without limitation, by way of
     consolidation or merger or a sale of all or substantially all its assets)
     that holders of Common Stock shall be entitled to receive stock, securities
     or assets with respect to or in exchange for Common Stock, then, as a
     condition of such reorganization or reclassification, lawful and adequate
     provisions (in form satisfactory to Holders of at least a majority of the
     outstanding shares of Series B Preferred Stock) shall be made whereby each
     Holder of a share or shares of Series B Preferred Stock shall thereafter
     have the right to receive, upon the basis and upon the terms and conditions
     specified herein and in lieu of the shares of Common Stock of the
     Corporation immediately theretofore receivable upon the conversion of such
     share or shares of Series B Preferred Stock, such shares of stock,
     securities or assets as may be issued or payable with respect to or in
     exchange for a number of outstanding shares of such Common Stock equal to
     the number of shares of such stock immediately theretofore so receivable
     had such reorganization or reclassification not taken place, and in any
     such case appropriate provision shall be made with respect to the rights
     and interests of such Holder to the end that the provisions hereof
     (including without limitation provisions for adjustment of the Conversion
     Price) shall thereafter be applicable, as nearly as may be, in relation to
     any shares of stock, securities or assets thereafter deliverable upon the
     exercise of such conversion rights. In the event of a merger or
     consolidation of the Corporation as a result of 


<PAGE>
                                      -14-


     which a greater or lesser number of shares of common stock of the surviving
     corporation are issuable to holders of Common Stock of the Corporation
     outstanding immediately prior to such merger or consolidation, the
     Conversion Price in effect immediately prior to such merger or
     consolidation shall be adjusted in the same manner as though there were a
     subdivision or combination of the outstanding shares of Common Stock of the
     Corporation.

          (xi) Partial or Liquidating Distributions. In the event that the
     Corporation shall make any distribution of its assets upon or with respect
     to the Common Stock, as a liquidating or partial liquidating dividend, or
     other than as a dividend payable out of earnings, the Holder of each
     outstanding share of Series B Preferred Stock shall, upon the exercise of
     his or her right to convert after the record date for such distribution or,
     in the absence of a record date, after the date of such distribution,
     receive, in addition to the number of shares of Common Stock for which such
     shares of Series B Preferred Stock are then convertible, the amount of such
     assets (or, at the option of the Corporation, a sum equal to the value
     thereof at the time of distribution as determined by the Board of Directors
     in its sole discretion) that would have been distributed to such Holder if
     he had exercised his right to convert immediately prior to the record date
     for such distribution or, in the absence of a record date, immediately
     prior to the date of such distribution.

     (D) Notwithstanding the foregoing provisions of this Section 6, (i) no
adjustment in the number of shares of Common Stock into which any share of
Series B Preferred Stock is convertible shall be required unless such adjustment
would require an increase or decrease in such number of shares of at least 1%
and (ii) no adjustment in the Conversion Price shall be required unless such
adjustment would require an increase or decrease in the Conversion Price of at
least $.01 per share; provided, however, that any adjustments which by reason of
this paragraph (D) are not required to be made shall be carried forward and
taken into account in any subsequent adjustment. All calculations under this
Section 6 shall be made to the nearest cent or the nearest 1/100th of a share,
as the case may be.


<PAGE>
                                      -15-


     (E) Whenever any adjustment is required in the shares into which any share
of Series B Preferred Stock is convertible, the Corporation shall forthwith (i)
file with each office or agency then maintained by the Corporation for the
transfer of the Series B Preferred Stock a statement describing in reasonable
detail the adjustment and the method of calculation used and (ii) cause a notice
of such adjustment, setting forth the adjusted Conversion Price to be mailed to
the Holders of record of shares of Series B Preferred Stock at their respective
addresses as shown on the stock books of the Corporation.

     (F) All shares of Series B Preferred Stock that shall have been surrendered
for conversion as herein provided shall no longer be deemed to be outstanding
and all rights with respect to such shares, including the rights, if any, to
receive notices and to vote, shall forthwith cease, except only the right of the
Holders thereof, subject to the provisions of this Section 6, to receive shares
of Common Stock in exchange therefor.

     (G) In the event that:

          (i) the Corporation shall take action to make any distribution (other
     than cash dividends payable out of earnings) to the holders of its Common
     Stock;

          (ii) the Corporation shall take action to offer for subscription pro
     rata to the holders of its Common Stock any securities of any kind;

          (iii) the Corporation shall take action to accomplish any capital
     reorganization, or reclassification of the capital stock of the Corporation
     (other than a subdivision, split or combination of its Common Stock), or a
     consolidation or merger to which the Corporation is a party and for which
     approval of any stockholders of the Corporation is required, or the sale or
     transfer of all or substantially all of the assets of the Corporation; or

          (iv) the Corporation shall take action looking to a voluntary or
     involuntary dissolution, liquidation or winding-up of the Corporation;

then the Corporation shall (A) in case of any such distribution or subscription
rights, at least thirty (30) days prior to the date or expected date on which
the stock books of the Corpora-


<PAGE>
                                      -16-


tion shall close or a record shall be taken for the determination of holders
entitled to such distribution or subscription rights, and (B) in the case of any
such reorganization, reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding-up, at least thirty day's (30) prior to the
date or expected date when the same shall take place, cause written notice
thereof to be mailed to each Holder of shares of Series B Preferred Stock at his
address as shown on the stock books of the Corporation. Such notice in
accordance with the foregoing clause (A) shall also specify, in the case of any
such distribution or subscription rights, the date or expected date on which the
holders of Common Stock shall be entitled thereto, and such notice in accordance
with the foregoing clause (B) shall also specify the date or expected date on
which the holders of Common Stock shall be entitled to exchange their Common
Stock for securities or other property deliverable upon such reorganization,
reclassification, consolidation, merger, sale, transfer, dissolution,
liquidation or winding-up, as the case may be.

     (H) For the purposes of this paragraph (6), the term "Common Stock" shall
mean (i) the class of stock designated as the Common Stock of the Corporation on
the date of this Certificate or (ii) any other class of stock resulting from
successive changes or reclassifications of such Common Stock consisting solely
of changes in par value or from no par value to par value, or from par value to
no par value. In the event that at any time as a result of an adjustment made
pursuant to the provisions of paragraph (C) of this Section 6, the Holder of any
share of Series B Preferred Stock thereafter surrendered for conversion shall
become entitled to receive any shares of the Corporation other than shares of
Common Stock, thereafter the number of such other shares so receivable upon
conversion of any share of Series B Preferred Stock shall be subject to
adjustment from time to time in a manner and on terms as nearly equivalent as
practicable to the provisions with respect to the Common Stock contained in
paragraph (C) of this Section 6, and the other provisions of this Section 6 with
respect to the Common Stock shall apply on like terms to any such other shares.

     (I) The Corporation shall not be required to issue fractional shares of
Common Stock upon the conversion of any Series B Preferred Stock. If more than
one share of Series B Preferred Stock shall be surrendered for conversion at one
time by the same Holder, the number of full shares of Common Stock issuable upon
conversion thereof shall be com-


<PAGE>
                                      -17-


puted on the basis of the aggregate number of shares so surrendered. If any
fractional interest in a share of Common Stock would be deliverable upon the
conversion of any shares of Series B Preferred Stock, the Corporation may pay,
in lieu thereof, in cash the Quoted Price thereof as of the Business Day
immediately preceding the date of such conversion.

     (J) The Corporation shall at all times reserve and keep available, free
from preemptive rights, out of its authorized but unissued stock, for the
purpose of effecting the conversion or redemption of the shares of Series B
Preferred Stock, such number of its duly authorized shares of Common Stock (or
treasury shares as provided below) as shall from time to time be sufficient to
effect the payment of dividends on the Series B Preferred Stock in shares of
Common Stock, the conversion of all outstanding shares of Series B Preferred
Stock into Common Stock at any time and the redemption of all outstanding shares
of Series B Preferred Stock for shares of Common Stock; provided, however, that
nothing contained herein shall preclude the Corporation from satisfying its
obligations in respect of the payment of dividends in shares of Common Stock or
the conversion of the Series B Preferred Stock by delivery of shares of Common
Stock that are held in the treasury of the Corporation. The Corporation shall,
from time to time and in accordance with the General Corporation Law of the
State of Delaware, cause the authorized number of shares of Common Stock to be
increased if the aggregate of the number of authorized shares of Common Stock
remaining unissued and the issued shares of such Common Stock in its treasury
(other than any shares of such Common Stock reserved for issuance in any other
connection) shall not be sufficient to permit the payment of dividends in shares
of Common Stock, the conversion of all outstanding shares of Series B Preferred
Stock into Common Stock or the redemption of all outstanding shares of Series B
Preferred Stock for shares of Common Stock.

     7. Optional Redemption.

     (A) The Corporation's Right To Redeem the Series B Preferred Stock. The
Series B Preferred Stock may be redeemed (subject to contractual and other
restrictions with respect thereto and the legal availability of funds therefor)
at the option of the Corporation in whole or, from time to time, in part
(provided that no less than 25% of the shares of Series B Preferred Stock then
outstanding may be redeemed at any one time) in the manner provided in Section

<PAGE>
                                      -18-


7(C) hereof (i) at any time after December 31, 1996 or (ii) on or prior to
December 31, 1996 if the Quoted Price of the Common Stock is at least 175% of
the Conversion Price (as last adjusted and in effect) for at least ten (10)
trading days selected by the Corporation within a period of any twenty (20)
consecutive trading days.

     (B) Consideration for Shares of Series B Preferred Stock To Be Redeemed.

          (i) If on the date prior to the determination of the Board of
     Directors to redeem Series B Preferred Stock, the Quoted Price of the
     Common Stock is equal to or greater than 105% of the Conversion Price (as
     last adjusted and in effect on such date) then the Series B Preferred Stock
     to be redeemed may be redeemed, at the option of the Corporation, for any
     combination of (x) shares of Common Stock, each share of Series B Preferred
     Stock to be redeemed for such number of fully, paid and non-assessable
     shares (as calculated to the nearest 1/100th of a share) as is obtained by
     dividing 1000 by the Conversion Price (as last adjusted and in effect on
     such date) and (y) the Cash Redemption Price.

          (ii) If on the date prior to the determination of the Board of
     Directors to redeem Series B Preferred Stock, the Quoted Price of the
     Common Stock is less than 105% of the Conversion Price (as last adjusted
     and in effect on such date) then the Series B Preferred Stock to be
     redeemed shall be redeemed for the Cash Redemption Price.

          (iii) In addition to (i) or (ii) above, the Corporation shall pay to
     each holder of shares of Series B Preferred Stock to be redeemed all
     accrued and unpaid dividends, if any, on such shares of Series B Preferred
     Stock to the Redemption Date payable in cash or shares of Common Stock or a
     combination thereof as determined in accordance with Section 3(B).

          (iv) The aggregate amount of cash or shares of Common Stock or
     combination of cash and shares of Common Stock to be received by Holders of
     Series B Preferred Stock pursuant to subparagraphs (i), (ii) and (iii)
     above are referred to herein as the "Redemption Consideration".


<PAGE>
                                      -19-


          (C) Procedure for Redemption.

          (i) In the event of a redemption of less than all of the Series B
     Preferred Stock, the shares so redeemed will be determined by the
     Corporation pro rata according to the number of shares held by each Holder,
     except that the Corporation may redeem all of the shares held by any
     Holders of fewer than 100 shares (or all of the shares held by Holders who
     would hold less than 100 shares as a result of such redemption).

          (ii) The Corporation shall send a written notice of redemption (the
     "Redemption Notice") by first-class mail, postage prepaid, not fewer than
     fifteen (15) days nor more than sixty (60) days prior to the Redemption
     Date to each Holder as of the record date fixed for such redemption of
     Series B Preferred Stock at such Holder's address as the same appears on
     the stock books of the Corporation; provided, however, that no failure to
     give such notice to any Holder or Holders nor any deficiency therein shall
     affect the validity of the procedure for the redemption of any shares of
     Series B Preferred Stock to be redeemed except as to the Holder or Holders
     to whom the Corporation has failed to give said notice or except as to the
     Holder or Holders whose notice was defective. The Redemption Notice shall
     state:

               (A) whether all or less than all the outstanding shares of Series
          B Preferred Stock are to be redeemed and the total number of shares of
          Series B Preferred Stock being redeemed;

               (B) the number of shares of Series B Preferred Stock held of
          record by that specific Holder that the Corporation intends to redeem;

               (C) the Redemption Date;

               (D) the Redemption Consideration;

               (E) the manner and place or places at which payment for the
          shares called for redemption will, upon presentation and surrender to
          the Corporation of the Series B Preferred Stock Certificates
          evidencing the shares being redeemed, be made; and


<PAGE>
                                      -20-


               (F) that dividends on the shares of Series B Preferred Stock
          being redeemed shall cease to accrue on the Redemption Date.

          (iii) On the Redemption Date, the full Redemption Consideration shall
     become payable for the shares of Series B Preferred Stock being redeemed on
     the Redemption Date. As a condition of payment of the Redemption
     Consideration, each Holder of Series B Preferred Stock must surrender
     Series B Preferred Stock Certificates or Certificates representing the
     shares of Series B Preferred Stock being redeemed by the Corporation in the
     manner and at the place designated in the Redemption Notice. The full
     Redemption Consideration for such shares properly tendered for payment
     shall be paid to the person whose name appears on such certificate or
     certificates as the owner thereof, on and after the Redemption Date when
     and as certificates for the shares being redeemed are properly tendered for
     payment. Each surrendered Series B Preferred Stock Certificate shall be
     cancelled and retired. In the event that less than all of the shares
     represented by any such certificate are redeemed, a new certificate shall
     be issued representing the unredeemed shares.

          (iv) On the Redemption Date, unless the Corporation defaults in the
     payment of the Redemption Consideration, dividends will cease to accrue
     with respect to the shares of Series B Preferred Stock called for
     redemption. All rights of Holders of such redeemed shares will terminate
     except for the right to receive the Redemption Consideration.

     8. Payment on Liquidation.

     (A) Upon any voluntary or involuntary liquidation, dissolution or
winding-up of the Corporation, Holders of Series B Preferred Stock will be
entitled to receive an amount in cash equal to the Liquidation Preference,
before any distribution is made on any Common Stock or other preferred stock of
the Corporation. After payment of the full amount of the Liquidation Preferences
to which they are entitled, Holders of Series B Preferred Stock will not be
entitled to any further participation in any distribution of assets of the
Corporation.


<PAGE>
                                      -21-


     (B) For the purposes of this Section 8, neither the voluntary sale,
conveyance, exchange or transfer (for cash, shares of stock, securities or other
consideration) of all or substantially all the property or assets of the
Corporation nor the consolidation or merger of the Corporation with one or more
corporations shall be deemed a voluntary or involuntary liquidation, dissolution
or winding-up of the Corporation, unless such sale, conveyance, exchange or
transfer shall be in connection with a dissolution or winding-up of the business
of the Corporation.

     9. Exclusion of Other Rights. Except as may other wise be required by the
General Corporation Law of the State of Delaware, shares of the Series B
Preferred Stock shall not have any preferences or relative, participating,
optional or other special rights, other than those specifically set forth in
this resolution and in the Certificate of Designation filed pursuant hereto (as
such Certificate may be amended from time to time) and in the Corporation's
Certificate of Incorporation, as amended. No shares of Series B Preferred Stock
shall have any preemptive or subscription rights whatsoever as to any securities
of the Corporation.

     10. Reissuance of Preferred Stock. Shares of Series B Preferred Stock that
have been issued and reacquired in any manner, including shares purchased or
redeemed, shall (upon compliance with any applicable provisions of the General
Corporation Law of the State of Delaware) have the status of authorized and
unissued shares of preferred stock undesignated as to series and may be
redesignated and reissued as part of any series of preferred stock.

     11. Business Day. If any payment or redemption shall be required by the
terms hereof to be made on a day that is not a Business Day, such payment,
redemption or exchange shall be made on the immediately succeeding Business Day.

     12. Headings of Subdivisions. The headings of the various subdivisions
hereof are for convenience of reference only and shall not affect the
interpretation of any of the provisions hereof.

     13. Severability of Provisions. If any right, preference or limitation of
the Series Preferred Stock set forth in this resolution and in the Certificate
of Designation filed pursuant hereto (as such Certificate may be amended from
time to time) is invalid, unlawful or incapable of being enforced by reason of
any rule or law or public policy, all other rights, 


<PAGE>
                                      -22-


preferences and limitations set forth in such Certificate of Designation (as so
amended) which can be given effect without the invalid, unlawful or
unenforceable right, preference or limitation shall, nevertheless, remain in
full force and effect, and no right, preference or limitation herein set forth
shall be deemed dependent upon any other such right, preference or limitation
unless so expressed herein.

     14. Notice. All notices and other communications provided for or permitted
to be given to the Corporation hereunder shall be made by hand delivery, next
day air courier or certified first-class mail to the Corporation at its
principal executive offices (currently located on the date of the adoption of
these resolutions at 2910 Seventh Street, Berkeley, California 94710, Attention:
General Counsel; with a copy to: Cahill Gordon & Reindel, Attention: Roger
Meltzer, Esq.

     15. Transferability; Right of Transferees.

     (A) From and after the date of original issuance of the Series B Preferred
Stock, the Series B Preferred Stock may not be sold, assigned, conveyed,
transferred, pledged, hypothecated or otherwise disposed of, and no Holder shall
agree to sell, assign, convey, transfer, pledge, hypothecate or otherwise
dispose of, any Series B Preferred Stock except in a Permitted Transfer. No
Holder shall consummate or agree to consummate a Permitted Transfer or series of
Permitted Transfers involving, individually or in the aggregate, 5,000 or more
shares of Series B Preferred Stock to a single Eligible Transferee or a number
of related or affiliated Eligible Transferees other than wholly-owned Affiliates
of Ortelius and GDK, without the prior written consent of the Corporation, which
consent shall not be unreasonably withheld.

     (B) The Series B Preferred Stock Certificates representing all of the
shares of Series B Preferred Stock to be transferred pursuant to a Permitted
Transfer shall be duly endorsed by the transferring Holder or by his duly
authorized attorney or representative, or accompanied by proper evidence of
succession, assignment or authority to transfer. In all cases of a Permitted
Transfer by an attorney, the original power of attorney, duly approved, or a
copy thereof, duly certified, shall be deposited and remain with the
Corporation. In case of a Permitted Transfer by executors, administrators,
guardians or other legal representatives, duly authenticated evidence of their
authority shall be produced, and may be required to be deposited and 


<PAGE>
                                      -23-


to remain with the Corporation in its discretion. Upon any registration of a
Permitted Transfer, the Corporation shall deliver new Series B Preferred Stock
Certificates to the persons entitled to the shares of Series B Preferred Stock
represented thereby. The Series B Preferred Stock Certificates may be exchanged
at the option of the Holder thereof, when surrendered at the offices of the
Corporation, for other Series B Preferred Stock Certificates of different
denominations, of like tenor and representing in the aggregate a like number of
shares of Series B Preferred Stock. Any Series B Preferred Stock Certificate so
surrendered shall be promptly cancelled by the Corporation and retired. Each
Series B Preferred Stock Certificate issued in exchange as provided above shall
be substantially in the form of the Series B Preferred Stock Certificate being
exchanged and shall be subject to all of the terms and provisions hereof.

     (C) The Series B Preferred Stock Certificates shall contain the following
legend:

     THE SENIOR CONVERTIBLE PREFERRED STOCK, SERIES B (THE "SERIES B PREFERRED
STOCK") EVIDENCED HEREBY IS SUBJECT TO SIGNIFICANT RESTRICTIONS ON
TRANSFERABILITY AND HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "ACT"), OR ANY STATE SECURITIES LAWS AND THE SERIES B PREFERRED
STOCK AND THE SHARES OF COMMON STOCK OR OTHER SECURITIES ISSUABLE UPON
CONVERSION OR REDEMPTION OF THE SERIES B PREFERRED STOCK MAY NOT BE OFFERED OR
SOLD EXCEPT PURSUANT TO (i) AN EFFECTIVE REGISTRATION STATEMENT, OR (ii) AN
EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE ACT AND APPLICABLE STATE SECURITIES LAWS AND AN OPINION OF
COUNSEL REASONABLY SATISFACTORY TO COUNSEL FOR XOMA CORPORATION THAT AN
EXEMPTION FROM REGISTRATION UNDER THE ACT IS AVAILABLE.

     16. Amendments. The Corporation shall amend this Certificate of Designation
as soon as practicable upon the determination of the Conversion Price in
accordance with the terms and conditions of a Securities Purchase Agreement of
even date herewith by and among Ortelius, GDK and the Corporation. This
Certificate of Designation may be amended without notice to or the consent of
any Holder to cure any ambiguity, defect or inconsistency provided that such
amendment does not adversely affect the rights of any Holder. Any provisions of
this Certificate of Designation may be amended by the Corporation with the
written consent of Holders representing a majority of the outstanding shares of
Series B Preferred Stock.


<PAGE>
                                      -24-


     The Corporation will, so long as any shares of Series B Preferred Stock are
outstanding, maintain an office or agency where such shares may be presented for
registration or transfer and where such shares may be presented for conversion
and redemption.




<PAGE>
                                      -25-


     IN WITNESS WHEREOF, XOMA Corporation has caused this Certificate of
Designation of Preferences and Rights of its Series B Preferred Stock to be
signed and attested by its duly authorized officers, this 18th day of November,
1993.

                                XOMA CORPORATION


                                By:  /s/ John L. Castello
                                     ---------------------------------
                                         John L. Castello
                                         Chairman, President and
                                           Chief Executive Officer

ATTEST:


By:  /s/ Christopher J. Margolin
     --------------------------------
         Christopher J. Margolin
         Secretary




                                XOMA CORPORATION
                             1981 STOCK OPTION PLAN

                        (As Amended and Restated Through
                                October 30, 1996)


     1. PURPOSE OF THE PLAN

     The 1981 Stock Option Plan ("Plan") is intended to promote the interests of
Xoma Corporation (the "Corporation") by providing (i) those key employees of the
Corporation and its subsidiaries who are primarily responsible for the
management, growth and financial success of the Corporation or its subsidiaries
and (ii) those consultants who provide valuable services to the Corporation or
its subsidiaries, with the opportunity to acquire a proprietary interest, or
increase their proprietary interest, in the Corporation and thereby encourage
such individuals to remain in the employ or service of the Corporation or its
subsidiaries.

     2. ADMINISTRATION OF THE PLAN

     (a) The Plan shall be administered by the Corporation's Board of Directors
(the "Board"). The Board, however, may at any time appoint a committee
("Committee") of two (2) or more "non-employee directors" (within the meaning of
Rule 16b-3(b)(3) of the Securities and Exchange Commission as amended in 1996 or
any successor provision thereto) to administer one or more provisions of the
Plan, including the option grant, option surrender and option acceleration
provisions, or to provide recommendations to the Board with respect to the
Board's administration of those provisions. It is also intended that the
non-employee directors shall also be "outside directors" (within the meaning of
Section 162(m) of the Internal Revenue Code). However, the mere fact that a
Committee member shall fail to qualify as a non-employee director or an outside
director shall not invalidate any options granted by the Committee which are
otherwise validly made under the Plan. Members of the Committee shall serve for
such period of time as the Board may determine and shall be subject to removal
by the Board at any time.

     (b) The Plan Administrator (either the Board or the Committee, to the
extent the Committee has been delegated responsibility for the administration of
the Plan) shall have full power and authority (subject to the provisions of the
Plan) to establish such rules and regulations as it may deem appropriate for the
proper administration of the Plan and to 


<PAGE>
                                      -2-


make such determinations under, and issue such interpretations of, the Plan and
any outstanding option as it may deem necessary or advisable. Decisions of the
Plan Administrator shall be final and binding on all parties who have an
interest in the Plan or any outstanding option.

     3. ELIGIBILITY FOR OPTION GRANTS

     (a) Key employees (including officers and directors) of the Corporation (or
its subsidiaries) and consultants (other than non-employee directors) who
provide valuable services to the Corporation (or its subsidiaries) are eligible
to receive options under the Plan. Directors who are not employees of the
Corporation (or its subsidiaries) are not eligible to receive such options or to
participate otherwise in the Plan.

     (b) The Committee, or the Board if no Committee is appointed pursuant to
subsection 2(a), shall have full authority to determine the number of shares to
be covered by each option grant, the time or times at which each granted option
is to become exercisable, the maximum term for which the option may remain
outstanding and whether the granted option is to be an incentive stock option
("Incentive Option") which satisfies the requirements of Section 422A of the
Internal Revenue Code or a non-statutory option not intended to meet such
requirements.

     (c) For the purposes of the Plan, each corporation (other than the
Corporation) in an unbroken chain of corporations beginning with the Corporation
will be considered to be a subsidiary of the Corporation, provided each such
corporation other than the last corporation in the unbroken chain owns, at the
time of determination, stock possessing 50% or more of the total combined voting
power of all classes of stock in one of the other corporations in such chain.

     4. STOCK SUBJECT TO THE PLAN

     (a) The stock issuable under the Plan shall be shares of the Corporation's
authorized but unissued or reacquired common stock ("Common Stock"). The maximum
number of shares issuable over the term of the Plan shall not exceed 5,150,000
shares, subject to adjustment as provided in Section 4(c). The maximum number of
shares of Common Stock authorized for issuance under the Plan shall, however, be
reduced, on a one-for-one basis, for each share of Common Stock issued under the
Corporation's Restricted Stock Plan (the "Stock Plan").


<PAGE>
                                      -3-


     For any one individual, the number of shares for which options or stock
appreciation rights may be granted under the Plan, beginning October 30, 1996
and ending at the expiration of the term of the Plan, may not exceed 1,000,000.

     (b) Should an option be terminated for any reason prior to exercise or
surrender in full, the shares subject to the portion of the option not so
exercised or surrendered shall be available for subsequent option grant under
the Plan or for subsequent option grant or stock issuance under the Stock Plan.
Shares subject to an option (or portion of an option) surrendered in accordance
with Section 7 of the Plan and shares repurchased by the Corporation pursuant to
its repurchase rights under the Plan shall not be available for subsequent
reissue under either this Plan or the Stock Plan.

     (c) If any change is made to the Common Stock issuable under the Plan by
reason of any stock dividend, stock split, combination of shares,
recapitalization, or other change affecting the outstanding common stock as a
class without receipt of consideration, then appropriate adjustments will be
made to (i) the maximum number of shares issuable under the Plan and (ii) the
number and/or class of shares and the option price per share of the Common Stock
subject to each outstanding option in order to prevent the dilution or
enlargement of benefits thereunder. The adjustments determined by the Plan
Administrator will be final, binding and conclusive.

     (d) Common Stock issuable upon exercise of an option granted under the Plan
may be subject to such restrictions on transfer, repurchase rights or other
restrictions as are determined by the Plan Administrator.

     5. TERMS AND CONDITIONS OF OPTIONS

     Each option granted under the Plan shall be evidenced by a stock option
agreement that complies with (or incorporates) each of the terms and conditions
of this Section 5 and identifies such option as either an Incentive Option or
non-statutory option. Individuals who are not employees of the Corporation or
its subsidiaries may only be granted non-statutory options. Each instrument
evidencing an Incentive Option shall, in addition, comply with the applicable
provisions of Section 6.


<PAGE>
                                      -4-


     (a) Option Price.

     (1) Subject to the provisions of subsection (a)(2) below, the option price
per share will be fixed by the Plan Administrator but in no event shall it be
less than one hundred percent (100%) of the fair market value per share of
Common Stock on the date of the option grant.

     (2) If the individual to whom an Incentive Option or a non-statutory option
is granted is at such time the owner of stock (as determined under Section
425(d) of the Internal Revenue Code) possessing 10% or more of the total
combined voting power of all classes of stock of the Corporation or any one of
its subsidiary corporations (such person to be herein referred to as a "10%
Shareholder"), then the option price per share shall not be less than one
hundred ten percent (110%) of the fair market value per share of Common Stock on
the grant date.

     (3) The option price shall become immediately due upon exercise of the
option and, subject to the provisions of Section 10, shall be payable in one of
the following alternative forms specified below (as determined by the Plan
Administrator and set forth in the instrument evidencing the grant):

          (A) Full payment in cash or cash equivalents; or

          (B) Full payment in shares of Common Stock valued at fair market value
     on the Exercise Date (as such term is defined below) in an amount equal to
     the option price; or

          (C) Full payment in a combination of shares of Common Stock valued at
     fair market value on the Exercise Date and cash or cash equivalents, equal
     in the aggregate to the option price; or

          (D) Payment effected through a broker-dealer sale and remittance
     procedure pursuant to which the optionee (I) shall provide irrevocable
     written instructions to the designated broker-dealer to effect the
     immediate sale of the purchased shares and remit to the Corporation, out of
     the sale proceeds, an amount equal to the aggregate option price payable
     for the purchased shares plus all applicable Federal and State income and
     employment taxes required to be withheld by the Corporation by reason of
     such purchase and (II) shall provide written di-


<PAGE>
                                      -5-


     rectives to the Corporation to deliver the certificates for the purchased
     shares directly to such broker-dealer.

For purposes of this subsection (a)(3), the Exercise Date is the date on which
written notice of the exercise of the option is given to the Corporation. Except
to the extent the sale and remittance procedure of clause (D) above is utilized,
payment of the option price for the purchased shares shall accompany such
notice.

     (4) For purposes of subsections (1), (2) and (3) above (and for all other
valuation purposes under the Plan), the fair market value per share of Common
Stock shall be determined in accordance with the following provisions:

          (A) If the Common Stock is not at the time listed or admitted to
     trading on any stock exchange but is traded in the over-the-counter market,
     the fair market value shall be the closing selling price per share of
     Common Stock on the date in question, as such price is reported by the
     National Association of Securities Dealers through its Nasdaq National
     Market or any successor system. If there is no reported closing selling
     price for Common Stock on the date in question, then the closing selling
     price on the last preceding date for which such quotation exists shall be
     determinative of fair market value.

          (B) If the Common Stock is at the time listed or admitted to trading
     on any stock exchange, then the fair market value shall be the closing
     selling price per share of Common Stock on the date in question on the
     stock exchange determined by the Plan Administrator to be the primary
     market for the Common Stock, as such price is officially quoted on such
     exchange. If there is no reported sale of Common Stock on such exchange on
     the date in question, then the fair market value shall be the closing
     selling price on the exchange on the last preceding date for which such
     quotation exists.

          (C) If the Common Stock is at the time neither listed nor admitted to
     trading on any stock exchange nor traded in the over-the-counter market (or
     if the Plan Administrator determines that the value as determined pursuant
     to subsection (A) or (B) above does not reflect fair market value), then
     the Plan Administrator shall determine fair market value after taking into
     ac-


<PAGE>
                                      -6-


     count such factors as it deems appropriate, including one or more
     independent professional appraisals.

     (b) Term and Exercise of Options; Transferability. Each option granted
under the Plan shall be exercisable at such time or times and during such period
as is determined by the Plan Administrator and set forth in the stock option
agreement evidencing such option; provided, however, that no option granted
under the Plan shall have a term in excess of ten (10) years from its date of
grant.

     Options (other than Incentive Options) may in the discretion of the Plan
Administrator, be granted on terms which permit their transfer or assignment to
the spouse of the optionee or a descendent of the optionee (any such spouse or
descendent, an "Immediate Family Member") or a corporation, partnership, limited
liability company or trust so long as all of the shareholders, partners, members
or beneficiaries thereof, as the case may be, are either the optionee or an
Immediate Family Member of the optionee, provided that (i) there may be no
consideration for any such transfer, (ii) the stock option agreement pursuant to
which such options are granted must expressly provide for transferability in a
manner consistent with the foregoing, and (iii) subsequent transfers of
transferred options will be prohibited other than by will or the laws of descent
and distribution. Following transfer, any such options will continue to be
subject to the same terms and conditions as were applicable immediately prior to
transfer, provided that for purposes of the option agreement the term "optionee"
will refer to the transferee. The events of termination of employment will
continue to be applied with respect to the original optionee, following which
the options will be exercisable by the transferee only to the extent, and for
the periods specified, in the option agreement. With respect to Incentive
Options, the option shall be exercisable during the lifetime of the optionee
only by the optionee and shall not be assignable or transferable by the optionee
otherwise than by will or by the laws of descent and distribution.

     (c) Investment Purpose. If necessary or advisable to comply with applicable
federal or state securities laws, any option granted under the Plan may be
granted on the condition that the optionee agree that the shares of Common Stock
purchased thereunder are for investment purposes only and not for resale or
distribution and that such shares shall be disposed of only in accordance with
such laws. As a condition to issuance of any shares purchased upon the exercise
of any option granted pursuant to the Plan, the optionee, his executor,
ad-


<PAGE>
                                      -7-


ministrator, heir, legatee or transferee (as the case may be) receiving such
shares may be required to deliver to the Corporation an instrument, in form and
substance satisfactory to the Corporation and its counsel, implementing such
agreement. Any such condition may be eliminated by the Plan Administrator if the
Plan Administrator determines it is no longer necessary or advisable.

     (d) Effect of Termination of Employment.

     (1) Should an optionee cease to be an employee of the Corporation for any
reason (including death or permanent disability as defined in Section 22(e)(3)
of the Internal Revenue Code) while the holder of one or more outstanding
options granted to such optionee under the Plan, then such option or options
shall not remain exercisable (except as otherwise specifically authorized under
Section 11) for more than a twelve (12) month period (or such shorter period as
is determined by the Plan Administrator and set forth in the option agreement)
following the date of such cessation of employee status, and each such option
shall, during such twelve (12) month or shorter period, be exercisable only to
the extent of the number of shares (if any) for which the option is exercisable
on the date of such cessation of employee status. Under no circumstances,
however, shall any such option be exercisable after the specified expiration
date of the option term. Upon the expiration of such twelve (12) month or
shorter period or (if earlier) upon the expiration of the option term, the
option shall terminate and cease to be exercisable.

     (2) Any option granted to an optionee under the Plan and exercisable in
whole or in part on the date of the optionee's death may be subsequently
exercised, but only to the extent of the number of shares (if any) for which the
option is exercisable on the date of the optionee's cessation of employee
status, by the personal representative of the optionee's estate or by the person
or persons to whom the option is transferred pursuant to subsection (b) above,
provided and only if such exercise occurs prior to the earlier of (i) the first
anniversary of the date of the optionee's death or (ii) the specified expiration
date of the option term. Upon the occurrence of the earlier event, the option
shall terminate and cease to be exercisable.

     (3) If (i) the optionee's status as an employee is terminated for cause
(including, but not limited to, any act of dishonesty, willful misconduct, fraud
or embezzlement or any unauthorized disclosure or use of confidential
information or 


<PAGE>
                                      -8-


trade secrets) or (ii) the optionee makes or attempts to make any unauthorized
use or disclosure of confidential information or trade secrets of the
Corporation or its subsidiaries, then upon the occurrence of any such event all
outstanding options granted the optionee under the Plan shall immediately
terminate and cease to be exercisable.

     (4) Notwithstanding subsections (1), (2) and (3) above, the Plan
Administrator shall have the discretion to establish as a provision applicable
to the exercise of one or more options granted under the Plan that during the
period of exercisability following cessation of employee status (as provided in
such subsections), the option may be exercised not only with respect to the
number of shares for which it is exercisable at the time of the optionee's
cessation of employee status but also with respect to one or more installments
of purchasable shares for which the option otherwise would have become
exercisable had such cessation of employee status not occurred.

     (5) For purposes of the foregoing provisions of this Section 5(d), the
optionee shall be deemed to be an employee of the Corporation for so long as the
optionee remains in the employ of the Corporation or one or more of its
subsidiaries.

     (6) If the option is granted to a consultant or other independent
contractor, then the instrument evidencing the granted option shall include
provisions comparable to subsections 5(d)(1), 5(d)(2) and 5(d)(3) above, and may
include provisions comparable to subsection 5(d)(4) above, with respect to the
optionee's termination of service with the Corporation or its subsidiaries.

     (e) Shareholder Rights. An option holder shall have no shareholder rights
with respect to any shares covered by the option until such option holder has
exercised the option, paid the option price and been issued a stock certificate
for the purchased shares.

     (f) Repurchase Rights. The shares of Common Stock acquired upon the
exercise of options granted under the Plan may be subject to one or more
repurchase rights of the Corporation in accordance with the following
provisions:

     (1) The Plan Administrator may in its discretion determine that it shall be
a term and condition of one or more options granted under the Plan that the
Corporation (or 


<PAGE>
                                      -9-


its assigns) shall have the right, exercisable upon the optionee's cessation of
employee status or service, to repurchase at the original option price any or
all unvested shares of Common Stock at the time held by such individual under
the Plan. Any such repurchase right shall be exercisable by the Corporation (or
its assigns) upon such terms and conditions (including the establishment of the
appropriate vesting schedule and other provisions for the expiration of such
right in one or more installments) as the Plan Administrator may specify in the
instrument evidencing such right.

     (2) The Plan Administrator shall also have full power and authority to
provide for the automatic termination of the Corporation's outstanding
repurchase rights, in whole and in part, and thereby accelerate the vesting of
any or all purchased shares, upon the occurrence of any Corporate Transaction
specified in Section 8.

     6. SPECIAL LIMITATIONS ON INCENTIVE OPTIONS

     The terms and conditions specified below shall be applicable to all
Incentive Options granted under the Plan. Options which are specifically
designated as "non-statutory" options when issued under the Plan shall not be
subject to such terms and conditions:

     (a) Prior Outstanding Option. Under no circumstances may an Incentive
Option that is granted before January 1, 1987 be exercised while there remains
outstanding (within the meaning of Section 422A(c)(7) of the Internal Revenue
Code) any other pre-1987 Incentive Option that was granted at an earlier date to
the option holder to purchase stock in the Corporation or any other entity which
is on the date of grant of the later option either a subsidiary corporation of
the Corporation or any predecessor of any of any such corporation.

     (b) Dollar Limitations.

     (1) Dollar Limitations on Incentive Options Granted After December 31,
1986. The aggregate fair market value (determined as of the respective date or
dates of grant) of the Common Stock for which one or more options granted after
December 31, 1986 to any employee under the Plan (or any other option plan of
the Corporation or its parent or subsidiary corporations) may for the first time
become exercisable as incentive stock options under the Federal tax laws during
any one post-1986 calendar year shall not exceed the sum of One Hundred Thousand
Dollars ($100,000). To the extent the employee holds 


<PAGE>
                                      -10-


two or more such post-1986 options which become exercisable for the first time
in the same calendar year, the foregoing limitation on the exercisability
thereof as incentive stock options under the Federal tax laws shall be applied
on the basis of the order in which such options are granted.

     (2) Dollar Limitation for Incentive Options Granted Before January 1, 1987.
The aggregate fair market value (determined as of the respective date or dates
of grant) of the Common Stock which may be made the subject of Incentive Options
granted under the Plan (or any other option plan of the Corporation or its
parent or subsidiary corporations) to any employee in any one calendar year
prior to the 1987 calendar year shall not exceed the sum of One Hundred Thousand
Dollars ($100,000), plus any unused Carryover to such pre-1987 calendar year.
For purposes of the preceding limitation, the term "Carryover" means one-half
(1/2) of the amount by which the sum of One Hundred Thousand Dollars ($100,000)
exceeds the aggregate fair market value (determined as of the respective date or
dates of grant) of the Common Stock for which the employee was previously
granted Incentive Options under the Plan (or any other option plan of the
Corporation or its parent or subsidiary corporations) in each calendar year
after 1980 and prior to 1987. The unused Carryover shall be available for each
of the three (3) pre-1987 calendar years immediately following the calendar year
in which the Carryover arises and shall increase the basic $100,000 limitation
otherwise applicable to the employee for each such pre-1987 calendar year by an
amount equal to the Carryover, less the portion thereof used in prior calendar
years. Incentive Options granted the employee during any pre-1987 calendar year
shall first be applied against the basic $100,000 limitation in effect for such
calendar year and then applied against any of the employee's unused Carryovers
to such calendar year, in the order in which such Carryovers arose in prior
calendar years.

     (c) 10% Shareholder. If the individual to whom the Incentive Option is
granted is a 10% Shareholder (as defined in Section 5(a)(2) above), then the
option shall not have a term in excess of five (5) years from such grant date.

     Except as modified by the preceding provision of this Section 6, all the
provisions of the Plan shall be applicable to the Incentive Options granted
hereunder.


<PAGE>
                                      -11-


     7. STOCK APPRECIATION RIGHTS

     (a) One or more option holders may, upon such terms and conditions as the
Plan Administrator may establish at the time of the option grant or at any time
thereafter, be granted the right to surrender all or part of an unexercised
option in exchange for a distribution from the Corporation in an amount equal to
the excess of (i) the fair market value (at date of surrender) of the number of
shares in which the optionee is at the time vested under the surrendered option
or portion thereof over (ii) the aggregate option price payable for such vested
shares. No surrender of an option, however, shall be effective unless it is
approved by the Plan Administrator. If the surrender is so approved, then the
distribution to which the option holder shall accordingly become entitled under
this Section 7 may be made in shares of Common Stock valued at fair market value
at date of surrender, in cash, or partly in shares and partly in cash, as the
Plan Administrator shall in its sole discretion deem appropriate.

     (b) If the surrender of an option is rejected by the Plan Administrator,
then the option holder shall retain whatever rights the option holder had under
the surrendered option (or surrendered portion thereof) on the date of surrender
and may exercise such rights at any time prior to the later of (i) the
expiration of the 5 business-day period following receipt of the rejection
notice or (ii) the last day on which the option is otherwise exercisable in
accordance with the terms of the instrument evidencing such option, but in no
event may such rights be exercised at any time after ten (10) years (or five (5)
years in the case of a 10% Shareholder) after the date of the option grant.

     (c) Notwithstanding the foregoing provisions of this Section 7, should
twenty-five percent (25%) or more of the Corporation's outstanding voting stock
be acquired pursuant to a tender or exchange offer (i) which is made by a person
or group of related persons other than the Corporation or a person that directly
or indirectly controls, is controlled by or is under common control with the
Corporation and (ii) which the Board does not recommend the Corporation's
shareholders to accept, then each officer or director who is at the time subject
to the short-swing profit restrictions of the Federal securities laws shall have
the right (exercisable for a period not to exceed thirty (30) days) to surrender
any or all options held by such individual under the Plan, to the extent such
options are at the time exercisable for vested shares, and receive in exchange
therefor an appreciation distribution from the Corporation cal-


<PAGE>
                                      -12-


culated in accordance with Section 7(a). The approval of the Plan Administrator
shall not be required for such surrender, and the distribution to which such
individual shall become entitled upon such surrender shall be made entirely in
cash.

     8. SALE, MERGER, REORGANIZATION, ETC.

     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Corporation is not the
     surviving entity, except for a transaction the principal purpose of which
     is to change the State of the Corporation's incorporation;

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Corporation; or

          (iii) any other business combination in which fifty percent (50%) or
     more of the Corporation's outstanding voting stock is transferred to
     different holders in a single transaction or a series of related
     transactions,

then each option at the time outstanding under the Plan and not then otherwise
fully exercisable shall, immediately prior to the specified effective date for
the Corporate Transaction, become fully exercisable for up to the total number
of shares of Common Stock purchasable under such option and may be exercised for
all or any portion of the shares for which the option is so accelerated.
However, an outstanding option shall not be so accelerated if and to the extent:
(i) such option is in connection with the Corporate Transaction either to be
assumed by the successor corporation or parent thereof or to be replaced with
comparable options to purchase capital stock of the successor corporation or
parent thereof, such comparability to be determined by the Plan Administrator,
or (ii) the acceleration of such option would, when added to the present value
of certain other payments in the nature of compensation which become due and
payable to such optionee in connection with the Corporate Transaction, result in
the payment to such individual of an excess parachute payment under Section
280G(b) of the Internal Revenue Code. The existence of any such excess parachute
payment shall be determined by the Plan Administrator in the exercise of its
reasonable business judgment and on the basis of independent tax counsel
provided the Corporation.


<PAGE>
                                      -13-


     (b) Upon the consummation of the Corporate Transaction, all outstanding
options under the Plan shall, to the extent not previously exercised or assumed
by the successor corporation or its parent company, terminate and cease to be
exercisable.

     (c) If the Corporation is the surviving entity in any Corporate Transaction
or the outstanding options under the Plan are to be assumed in connection with
such Corporate Transaction, then each such continuing or assumed option shall be
appropriately adjusted immediately after such Corporate Transaction to apply and
pertain to the number and class of securities which would have been issuable to
the optionee in consummation of the Corporate Transaction, had such option been
exercised immediately prior to the effective date of such Corporate Transaction.
Appropriate adjustments shall also be made to the option price payable per
share, provided the aggregate option price shall remain the same. In addition,
the class and number of securities available for issuance under the Plan
following the consummation of such Corporate Transaction shall be appropriately
adjusted.

     (d) In connection with any Corporate Transaction, the exercise of any
accelerated pre-1987 Incentive Option shall remain subject to the applicable
limitations of Section 6(a) and the exercisability as an incentive stock option
under the Federal tax laws of any accelerated post-1986 option shall be subject
to the applicable dollar limitation of Section 6(b)(1).

     (e) The grant of options under the Plan shall not affect the right of the
Corporation to adjust, reclassify, reorganize or otherwise change its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     9. [RESERVED]

     10. LOANS OR GUARANTEE OF LOANS

     The Plan Administrator may, in its discretion, assist any optionee
(including an optionee who is an officer or director of the Corporation) in the
exercise of one or more options granted to such optionee under the Plan,
including the satisfaction of any Federal and State income and employment tax
obligations arising therefrom, by (i) authorizing the extension of a loan from
the Corporation to such optionee, (ii) permitting the optionee to pay the option
price for the purchased Common Stock in installments over a period of years, or
(iii) 


<PAGE>
                                      -14-


authorizing a guarantee by the Corporation of a third-party loan to the
optionee. The terms of any loan, installment method of payment or guarantee
(including the interest rate and terms of repayment) shall be upon such terms as
the Plan Administrator specifies in the stock option agreement. Such loans,
installment payments and guarantees may be granted with or without security or
collateral, but the maximum credit available to the optionee may not exceed (A)
the aggregate option price for the purchased shares (less their par value, which
must in all events be paid in cash) plus (B) any Federal and State income and
employment tax liability incurred by the optionee in connection with such
exercise.

     11. EXTENSION PERIODS

     The Plan Administrator shall have full power and authority, exercisable in
its sole discretion, to extend, either at the time the option is granted or at
any time while the option remains outstanding, the period of time for which the
option is to remain exercisable following the optionee's termination of employee
status from the twelve (12) month or shorter period set forth in the option
agreement to such greater period of time as the Plan Administrator shall deem
appropriate; provided, however, that in no event shall such option be
exercisable after the specified expiration date of the option term.

     12. AMENDMENT OF THE PLAN AND OPTIONS

     (a) The Board has complete and exclusive power and authority to amend or
modify the Plan in any or all respects whatsoever; provided, however, that,
except to the extent necessary to qualify any or all options under the Plan as
Incentive Options, no such amendment or modification may adversely affect rights
and obligations of an option holder with respect to options at the time
outstanding under the Plan unless the option holder consents to such amendment.
In addition, the Board may not, without the approval of the Corporation's
shareholders, amend the Plan to (i) materially increase the maximum number of
shares issuable under the Plan (except for permissible adjustments under Section
4(c)), (ii) materially increase the benefits accruing to individuals who
participate in the Plan, or (iii) materially modify the class of individuals
eligible to receive options thereunder.

     (b) Options may be granted under the Plan to purchase shares of Common
Stock in excess of the number of shares then available for issuance under the
Plan, provided (i) an amendment to increase the maximum number of shares
issuable un-


<PAGE>
                                      -15-


der the Plan is adopted by the Board prior to the initial grant of any such
option and is thereafter submitted to the Corporation's shareholders for
approval and (ii) each option so granted is not to become exercisable, in whole
or in part, at any time prior to the obtaining of such shareholder approval.

     13. EFFECTIVE DATE AND TERM OF PLAN

     (a) The Plan was initially adopted by the Board on November 15, 1981 and
approved by the shareholders on May 10, 1982. The Plan was restated and amended
by the Board on April 3, 1987, and such restatement was approved by the
Corporation's shareholders on May 13, 1987. Amendments to the restated Plan were
adopted by the Board on September 20, 1988, December 16, 1988 and February 21,
1989 to increase the number of shares issuable under the Plan. Such amendments
were approved by the Corporation's shareholders on May 19, 1989. The Plan was
further amended and restated on March 21, 1990 and approved in 1991 to increase
the number of shares issuable under the Plan and to extend the term of the Plan
to March 21, 2000. The Plan was further restated and approved in 1992 to
increase the number of shares issuable under the Plan, and again in 1996 to
further increase the number of shares issuable under the Plan. The new
restatement of the Plan was adopted by the Board on October 30, 1996 and was
approved by the Corporation's shareholders at the 1997 Annual Meeting.

     (b) The provisions of this restated and amended Plan shall apply only to
options granted under the Plan from and after October 30, 1996. All options
issued and outstanding under the Plan immediately prior to October 30, 1996
shall continue to be governed by the terms and conditions of the Plan (and the
respective instruments evidencing each such option) as in effect on the date
each such option was previously granted, and nothing in this restatement shall
be deemed to affect or otherwise modify the rights or obligations of the holders
of such options with respect to the acquisition of shares of Common Stock
thereunder.

     (c) Unless sooner terminated in accordance with Section 8, the Plan will
terminate upon the earlier of (i) March 21, 2000 or (ii) the date on which all
shares available for issuance under the Plan have been issued or cancelled
pursuant to the exercise or surrender of options granted hereunder. If the date
of termination is determined under clause (i) above, then options outstanding on
such date shall not be affected by the termination of the Plan and will
thereafter continue to have 


<PAGE>
                                      -16-


force and effect in accordance with the provisions of the stock option
agreements evidencing such options.

     14. USE OF PROCEEDS

     Any cash proceeds received by the Corporation from the sale of shares
pursuant to options granted under the Plan shall be used for general corporate
purposes.

     15. WITHHOLDING

     The Corporation's obligation to deliver shares upon the exercise of any
option or the surrender of any option granted under the Plan is subject to the
option holder's satisfaction of all applicable Federal, State and local income
and employment tax withholding requirements.

     16. SPECIAL TAX WITHHOLDING ELECTION

     (a) The Plan Administrator may, in its discretion and in accordance with
the provisions of this Section 16 and such supplemental rules as the Plan
Administrator may from time to time adopt, provide any or all holders of
non-statutory options under the Plan with the election to have the Corporation
withhold, from the shares purchased under each non-statutory option, one or more
shares of Common Stock having an aggregate fair market value equal to the
designated percentage (any multiple of 5% up to 100% as specified by the
optionee) of the Federal and State tax liability incurred in connection with the
exercise of such non-statutory option. In addition, should the optionee deliver
shares acquired under the Stock Plan in payment of the option price for one or
more options exercised under the Plan and the Corporation cancel its first
refusal rights with respect to the delivered shares, the stock withholding
election may extend to the optionee's entire tax obligation with respect to both
the taxable gain on the purchased shares and the compensation income recognized
upon the cancellation of the Corporation's first refusal rights with respect to
the delivered shares.

     (b) Any such withholding election made by a holder of a non-statutory
option under the Plan shall be subject to the following terms and conditions:

          (i) The election must be made on or before the date the amount of the
     Federal and State withholding tax liability incurred in connection with the
     exercise of such non-statutory option is determined (the "Tax Determination
     Date").


<PAGE>
                                      -17-


          (ii) The election shall be irrevocable.

          (iii) The election shall be subject to the approval of the Plan
     Administrator, and no shares of Common Stock shall be accepted in
     satisfaction of the withholding taxes incurred in connection with the
     exercise of such option except to the extent the election is approved by
     the Plan Administrator.

          (iv) The shares of Common Stock to be withheld pursuant to the
     election shall be valued on the Tax Determination Date in accordance with
     the valuation procedures in effect under Section 5(a)(4).

          (v) In no event may the optionee's requested withholding exceed the
     dollar amount of the Federal and State income tax liability incurred as a
     result of the exercise of the non-statutory option.

     (c) In lieu of the direct withholding provisions of subparagraph (a) above,
one or more optionees may also be granted the election to deliver pre-existing
shares of Common Stock to the Corporation in satisfaction of the entire Federal
and State tax liability incurred in connection with the exercise of his/her
non-statutory stock option and delivery of any shares of Common Stock in payment
of the option price. The delivered shares shall be valued on the Tax
Determination Date in accordance with the valuation procedures in effect under
Section 5(a)(4).

     17. REGULATORY APPROVALS

     The implementation of the Plan, the granting of any option under the Plan,
and the issuance of Common Stock upon the exercise or surrender of any such
option is subject to the Corporation's procurement of all approvals and permits
required by regulatory authorities having jurisdiction over the Plan, the
options granted under it, and the Common Stock issued pursuant to it.



                             Stock Option Agreement


                           Under the XOMA Corporation


                             1981 Stock Option Plan


(A)            Optionee:                  (E)            Payroll Number:

(B)            Grant Date:                (F)            Expiration Date:

(C)            Shares:                    (G)            Exercise Price:

(D)            Share Installments:        (H)            Option Type:


     XOMA Corporation (the "Company") has granted you an option to purchase the
number of shares of Common Stock shown in item (C) above (the "Optioned Shares")
at the Exercise Price per share shown in item (G) above. This option is subject
to the terms of the Company's 1981 Stock Option Plan, as amended and restated
through October 30, 1996 (the "Plan") and to the terms and conditions set forth
in this Stock Option Agreement under the XOMA Corporation 1981 Stock Option Plan
(the "Agreement").

     The details of your option are as follows:

     1. Term; Transfer. The term of this option commences on the Grant Date
shown in item (B) above and, except as provided in Section 3 and Subsection 5(a)
hereof, expires at the close of business on the Expiration Date shown in item
(F) above, which is 10 years from the Grant Date.

     If this option is a non-statutory stock option, it may be transferred or
assigned to your spouse or descendent (any such spouse or descendent, your
"Immediate Family Member") or a corporation, partnership, limited liability
company or trust so long as all of the shareholders, partners, members or
beneficiaries thereof, as the case may be, are either you or your Immediate
Family Member, provided that (i) there may be no consideration for any such
transfer and (ii) subsequent transfers of the transferred option will be
prohibited other than by will or the laws of descent and distribution. Following
transfer, the option will continue to be subject to the same terms and
conditions as were applicable immediately prior to transfer, provided that for
purposes of this Agreement any references to "you" will refer to the transferee.
The events of termination of employment will continue to be applied with respect
to you, 


<PAGE>
                                       -2-


following which the option will be exercisable by the transferee only to the
extent, and for the periods specified, in this Agreement.

     If this option is an incentive stock option, the option shall be
exercisable during your lifetime only by you and shall not be assignable or
transferable otherwise than by will or by the laws of descent and distribution.

     2. Exercise Schedule. Provided that you remain an employee of or consultant
to the Company (as determined in accordance with Subsection 3(e) hereof), the
option granted herein will become exercisable in accordance with the following
schedule:

     (a) This option will become exercisable with respect to 20% of the Optioned
Shares after the expiration of one year from the Grant Date;

     (b) This option will become exercisable with respect to an additional 20%
of the Optioned Shares after the expiration of two years from the Grant Date;

     (c) This option will become exercisable with respect to an additional 20%
of the Optioned Shares after the expiration of three years from the Grant Date;

     (d) This option will become exercisable with respect to an additional 20%
of the Optioned Shares after the expiration of four years from the Grant Date;
and,

     (e) This option will become exercisable with respect to the remaining 20%
of the Optioned Shares after the expiration of five years from the Grant Date.

     Exercisable installments may be exercised in whole or in part in increments
of 25 or more shares and, to the extent not exercised, will accumulate and be
exercisable at any time on or before the Expiration Date or sooner termination
of the option term.

     3. Accelerated Termination of Option Term. The option term specified in
Section 1 will terminate (and this option will cease to be exercisable) prior to
the Expiration Date should one of the following provisions become applicable:

     (a) Except as otherwise provided in Subsections (b), (c) and (d) below, if
you cease to be an employee of the Company at 


<PAGE>
                                      -3-


any time during the option term, then the period for exercising this option will
be limited to the three-month period commencing with the date of such cessation
of employee status; provided that, notwithstanding the foregoing, if you cease
to be an employee of the Company and immediately thereafter become a consultant
to the Company at any time during the option term, then the period for
exercising this option will not be limited as aforesaid but will be limited to
the three-month period commencing with the date of cessation of consultant
status, if during the option term; and provided further, that in no event will
this option be exercisable at any time after the Expiration Date. During any
such limited period of exercisability, this option may not be exercised for more
than the number of Optioned Shares (if any) for which it is exercisable at the
date of your cessation of employee or consultant status, as the case may be.
Upon the expiration of any such limited period of exercisability or (if earlier)
upon the Expiration Date, this option will terminate and cease to be
outstanding.

     (b) If you die while this option is outstanding, then the personal
representative of your estate or the person or persons to whom the option is
transferred pursuant to your will, in accordance with the laws of descent and
distribution, or pursuant to Section 1 above, will have the right to exercise
this option, but only with respect to the number of Optioned Shares (if any) for
which it is exercisable at the date of your death. Such right will lapse, and
this option will cease to be exercisable, upon the earlier of (i) the expiration
of the one-year period measured from the date of your death or (ii) the
specified Expiration Date of the option term.

     (c) If you become permanently disabled and cease by reason thereof to be
either an employee of or a consultant to the Company at any time during the
option term, then you will have a period of twelve months (commencing with the
date of such cessation of employee or consultant status, as the case may be)
during which to exercise this option; provided, however, that in no event shall
this option be exercisable at any time after the Expiration Date. During such
limited period of exercisability, this option may not be exercised for more than
the number of Optioned Shares (if any) for which this option is exercisable at
the date of your cessation of employee or consultant status, as the case may be.
Upon the expiration of such limited period of exercisability or (if earlier)
upon the Expiration Date, this option will terminate and cease to be
outstanding. You will be deemed to be permanently disabled if you are, by reason
of any medically determinable physical or mental impairment expected to result
in death or to be of continuous 


<PAGE>
                                      -4-


duration of not less than twelve consecutive months or more, unable to perform
your usual duties for the Company or its subsidiaries.

     (d) Should (i) your status as either an employee or a consultant be
terminated for cause (including, but not limited to, any act of dishonesty,
willful misconduct, fraud or embezzlement or any unauthorized disclosure or use
of confidential information or trade secrets), or (ii) you make or attempt to
make any unauthorized use or disclosure of confidential information or trade
secrets of the Company or its subsidiaries, then in any such event this option
will terminate and cease to be exercisable immediately upon the date of such
termination of employee or consultant status, as the case may be, or such
unauthorized use or disclosure of confidential or secret information or attempt
thereat.

     (e) For purposes of this Agreement, you will be deemed to be an employee of
the Company for so long as you remain in the employ of the Company or one or
more of its subsidiaries, and you will be deemed to be a consultant to the
Company for so long as you are actively rendering consulting services on a
periodic basis to the Company or one or more of its subsidiaries. A corporation
will be deemed to be a subsidiary of the Company if it is a member of an
unbroken chain of corporations beginning with the Company, provided that each
such corporation in the chain (other than the last corporation) owns, at the
time of determination, stock possessing 50% or more of the total combined voting
power of all classes of stock in one of the other corporations in such chain.

     4. Adjustment in Option Shares.

     (a) If any change is made to the Common Stock issuable under the Plan,
whether by reason of any stock dividend, stock split, combination of shares,
recapitalization or other change affecting the outstanding Common Stock as a
class without receipt of consideration, then appropriate adjustments will be
made to (i) the total number of Optioned Shares subject to this option and (ii)
the Exercise Price payable per share, in order to reflect such change and
thereby preclude the dilution or enlargement of benefits under this Agreement.
The adjustments determined by the plan administrator (the "Plan Administrator")
will be final, binding and conclusive.

     (b) If the Company is the surviving entity in any merger or other business
combination, then this option, if outstanding under the Plan immediately after
such merger or other business 


<PAGE>
                                      -5-


combination, will be appropriately adjusted to apply and pertain to the number
and class of securities which the holder of the same number of shares of Common
Stock as are subject to this option immediately prior to such merger or other
business combination would have been entitled to receive in the consummation of
such merger or other business combination, and an appropriate adjustment will be
made to the Exercise Price payable per share, provided the aggregate Exercise
Price payable hereunder will remain the same.

     5. Corporate Transaction.

     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Company is not the surviving
     entity, except for a transaction the principal purpose of which is to
     change the State of the Company's incorporation,

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Company, or

          (iii) any other corporate reorganization or business combination in
     which fifty percent (50%) or more of the Company's outstanding voting stock
     is transferred to different holders in a single transaction or a series of
     related transactions,

then the exercisability of this option will automatically be accelerated so that
such option may be exercised simultaneously with consummation of such Corporate
Transaction for any or all of the Optioned Shares. No such acceleration of this
option will occur, however, if and to the extent: (x) the terms of the agreement
provide as a prerequisite to the consummation of such Corporate Transaction that
outstanding options under the Plan (including this option) are to be assumed by
the successor corporation or parent thereof or are to be replaced with the
comparable options to purchase shares of capital stock of the successor
corporation or parent thereof, such comparability to be determined by the Plan
Administrator, or (y) the acceleration of this option would, when added to the
present value of certain other payments in the nature of compensation which
become due and payable to you in connection with the Corporate Transaction,
result in the payment to you of excess parachute payments under Section 280G(b)
of the Internal Revenue Code. The existence of such excess parachute payments
will be determined by the Plan Administrator in the exercise of its reason-


<PAGE>
                                      -6-


able business judgment and on the basis of tax counsel provided to the Company.
Immediately following consummation of the Corporate Transaction, this option
will, to the extent not previously exercised or assumed by the successor
corporation or its parent company, terminate and cease to be exercisable.

     (b) The exercisability of this option as an incentive stock option under
the Federal tax laws (if designated as such above) will be subject to the
applicable dollar limitation of Section 16 hereof.

     (c) The Plan Administrator will use its best efforts to provide you with
written notice of a Corporate Transaction at least ten business days prior to
the effective date.

     (d) This Agreement will not in any way affect the right of the Company to
adjust, reclassify, reorganize or otherwise make changes in its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     6. Privilege of Stock Ownership. The holder of this option will not have
any rights of a shareholder with respect to the Optioned Shares until such
individual has exercised the option, paid the Exercise Price and been issued a
stock certificate for the purchased shares.

     7. Manner of Exercising Option.

     (a) In order to exercise this option with respect to all or any part of the
Optioned Shares for which this option is at the time exercisable, you (or in the
case of exercise after your death, your executor, administrator, heir, legatee
or transferee as the case may be) must take the following actions:

          (i) Provide the Secretary of the Company with written notice of such
     exercise, specifying the number of Optioned Shares with respect to which
     the option is being exercised.

          (ii) Pay the Exercise Price for the purchased Optioned Shares in one
     or more of the following alternative forms: (A) full payment in cash or by
     check payable to the Company's order; (B) full payment in shares of Common
     Stock of the Company valued at fair market value on the exercise date (as
     such terms are defined below); (C) full payment in combination of shares of
     Common Stock of the Company [held for at least six months1 and] valued at
     fair


<PAGE>
                                      -7-


     market value on the exercise date and cash or check payable to the
     Company's order; (D) payment effected through a broker-dealer sale and
     remittance procedure pursuant to which you (I) will provide irrevocable
     written instructions to the designated broker-dealer to effect the
     immediate sale of the purchased shares and remit to the Company, out of the
     sale proceeds, an amount equal to the aggregate Exercise Price payable for
     the purchased shares plus all applicable Federal and State income and
     employment taxes required to be withheld by the Company by reason of such
     purchase and (II) will provide written directives to the Company to deliver
     the certificates for the purchased shares directly to such broker-dealer;
     or, to the extent the Plan Administrator specifically authorizes such
     method of payment at the time of exercise, (E) payment by a full-recourse
     promissory note. Any such promissory note authorized by the Plan
     Administrator will be substantially in the form approved by the Plan
     Administrator, will bear interest at the minimum per annum rate necessary
     to avoid the imputation of interest income to the Company and compensation
     income to you under the Federal tax laws and will become due in full (in
     one or more consecutive annual installments measured from the execution
     date of the note) not later than the Expiration Date of this option.
     Payment of the note will be secured by the pledge of the purchased shares,
     and the pledged shares will be released only as the note is paid.

          (iii) Furnish to the Company appropriate documentation that the person
     or persons exercising the option, if other than you, have the right to
     exercise this option.

     (b) For purposes of Subsection 7(a) hereof, the fair market value per share
of Common Stock on any relevant date will be determined in accordance with
Subsections (i) through (iii) below, and the exercise date will be the date on
which you exercise this option in compliance with the provisions of Subsection
7(a).

          (i) If the Common Stock is not listed or admitted to trading on any
     stock exchange on the date in question, but is traded in the
     over-the-counter market, the fair market value will be the closing selling
     price per share of such stock on such date, as such price is reported by
     the National Association of Securities Dealers through its Nasdaq National
     Market. If there is no reported closing selling price of the stock on the
     date in question then the closing selling price on the last preceding date
     for 


<PAGE>
                                      -8-


     which such quotation exists will be determinative of fair market value.

          (ii) If the Common Stock is listed or admitted to trading on any stock
     exchange on the date in question, the fair market value will be the closing
     selling price per share of such stock on such date on the stock exchange
     determined by the Plan Administrator to be the primary market for such
     stock, as such price is officially quoted on such exchange. If there is no
     reported closing selling price of such stock on such exchange on the date
     in question, the fair market value will be the closing selling price on the
     exchange on the last preceding date for which such quotation exists.

          (iii) If the Common Stock is neither listed nor admitted to trading on
     any stock exchange nor traded in the over-the-counter market on the date in
     question or if the Plan Administrator determines that the quotations under
     Subsections (i) or (ii) above do not accurately reflect the fair market
     value of such stock, the fair market value will be determined by the Plan
     Administrator after taking into account such factors as the Plan
     Administrator may deem appropriate, including one or more independent
     professional appraisals.

     (c) In no event may this option be exercised for any fractional share.

     8. Compliance with Laws and Regulations.

     (a) The exercise of this option and the issuance of Optioned Shares upon
such exercise will be subject to compliance by the Company and by you with all
applicable requirements of law relating thereto and with all applicable
regulations of any stock exchange on which shares of the Company's Common Stock
may be listed at the time of such exercise and issuance.

     (b) In connection with the exercise of this option, you will execute and
deliver to the Company such representations in writing as may be requested by
the Company in order for it to comply with the applicable requirements of
Federal and State securities laws.

     9. Restrictive Legends. If and to the extent any Optioned Shares acquired
under this option are not registered under the Securities Act of 1933, the stock
certificates for such 


<PAGE>
                                      -9-


Optioned Shares will be endorsed with restrictive legends, including (without
limitation) the following:

          "The Shares represented by this certificate have not been registered
          under the Securities Act of 1933. The shares have been acquired for
          investment and may not be sold or offered for sale in the absence of
          (a) an effective registration statement for the shares under such Act,
          (b) a 'no action' letter of the Securities and Exchange Commission
          with respect to such sale or offer, or (c) an opinion of counsel to
          the Company that registration under such Act is not required with
          respect to such sale or offer."

     10. Successors and Assigns. Except to the extent otherwise provided in
Section 1 and Subsection 5(a), the provisions of this Agreement will inure to
the benefit of, and be binding upon your successors, administrators, heirs,
legal representatives and assigns and the successors and assigns of the Company.

     11. Liability of the Company.

     (a) If the Optioned Shares covered by this Agreement exceed, as of the
Grant Date, the number of shares of Common Stock which may without shareholder
approval be issued under the Plan, then this option will be void with respect to
such excess shares unless shareholder approval of an amendment sufficiently
increasing the number of shares of Common Stock issuable under the Plan is
obtained in accordance with the provisions of the Plan.

     (b) The inability of the Company to obtain approval from any regulatory
body having authority deemed by the Company to be necessary to the lawful
issuance and sale of any Common Stock pursuant to this option will relieve the
Company of any liability in respect of the non-issuance or sale of such stock as
to which such approval will not have been obtained.

     12. No Employment or Consulting Contract. Nothing in this Agreement or in
the Plan will confer upon you any right to continue in the employ or service of
the Company for any period of time or interfere with or otherwise restrict in
any way the rights of the Company (or any subsidiary of the Company employing or
retaining you) or you, which rights are hereby expressly reserved by each, to
terminate your employee or consultant 


<PAGE>
                                      -10-


status as the case may be, at any time for any reason whatsoever, with or
without cause.

     13. Notices. Any notice required to be given or delivered to the Company
under the terms of this Agreement will be in writing and addressed to the
Company in care of its Secretary at its corporate offices. Any notice required
to be given or delivered to you will be in writing and addressed to you at the
address indicated below your signature line herein. All notices will be deemed
to be given or delivered upon personal delivery or upon deposit in the U.S.
mail, postage prepaid and properly addressed to the party to be notified.

     14. Construction. This Agreement and the option evidenced hereby are made
and granted pursuant to the Plan and are in all respects limited by and subject
to the express terms and provisions of the Plan. Any dispute regarding the
interpretation of this Agreement will be submitted to the Plan Administrator for
resolution. The decision of the Plan Administrator will be final, binding and
conclusive. Questions regarding this option or the Plan should be referred to
the Paralegal Assistant in the Legal Department.

     15. Governing Law. The interpretation, performance, and enforcement of this
Agreement will be governed by the laws of the State of California.

     16. Additional Terms Applicable to an Incentive Stock Option. In the event
this option is an incentive stock option, the following terms and conditions
will apply to the grant:

     (a) This option will cease to qualify for favorable tax treatment as an
incentive stock option under the Federal tax laws if (and to the extent) this
option is exercised for Optioned Shares: (i) more than three months after the
date you cease to be an employee for any reason other than death or permanent
disability (as defined in Section 3) or (ii) more than one (1) year after the
date you cease to be an employee by reason of permanent disability.

     (b) Except in the event of a Corporate Transaction under Section 5, this
option will not become exercisable in the calendar year in which granted if (and
to the extent) the aggregate fair market value (determined at the Grant Date) of
the Company's Common Stock for which this option would otherwise first become
exercisable in such calendar year would, when added to the aggregate fair market
value (determined as of the 


<PAGE>
                                      -11-


respective date or dates of grant) of the Company's Common Stock for which this
option or one or more other post-1986 incentive stock options granted to you
prior to the Grant Date (whether under the Plan or any other option plan of the
Company or its parent or subsidiary corporations) first become exercisable
during the same calendar year, exceed One Hundred Thousand Dollars ($100,000) in
the aggregate. To the extent the exercisability of this option is deferred by
reason of the foregoing limitation, the deferred portion will first become
exercisable in the first calendar year or years thereafter in which the One
Hundred Thousand Dollar ($100,000) limitation of this Section 16(b) would not be
contravened.

     (c) Should the exercisability of this option be accelerated upon a
Corporate Transaction in accordance with Section 5, then this option will
qualify for favorable tax treatment as an incentive stock option under the
Federal tax laws only to the extent the aggregate fair market value (determined
at the Grant Date) of the Company's Common Stock for which this option first
becomes exercisable in the calendar year in which the Corporate Transaction
occurs does not, when added to the aggregate fair market value (determined as of
the respective date or dates of grant) of the Company's Common Stock for which
this option or one or more other post-1986 incentive stock options granted to
you prior to Grant Date (whether under the Plan or any other option plan of the
Company or any parent or subsidiary corporations) first become exercisable
during the same calendar year, exceed One Hundred Thousand Dollars ($100,000) in
the aggregate.

     (d) To the extent that this option fails to qualify as an incentive stock
option under the Federal tax laws, you will recognize compensation income in
connection with the acquisition of one or more Optioned Shares hereunder, and
you must make appropriate arrangements for the satisfaction of all Federal,
State or local income tax withholding requirements and Federal social security
employee tax requirements applicable to such compensation income.

     17. Additional Terms Applicable to a Non-Statutory Stock Option. In the
event this option is a non-statutory stock option, you hereby agree to make
appropriate arrangements with the Company or subsidiary thereof by which you are
employed or retained for the satisfaction of all Federal, State or local income
tax withholding requirements and Federal social security employee tax
requirements applicable to the exercise of this option.



<PAGE>
                                      -12-


                                 XOMA CORPORATION


                                 By:
                                     John L. Castello
                                     Chairman of the Board,
                                     President & Chief Executive
                                       Officer


                                 Dated:


     I hereby agree to be bound by the terms and conditions of this Agreement
and the Plan.


                                 By:



                                 Dated:


         If the optionee resides in California or another community property
jurisdiction, I, as the optionee's spouse, also agree to be bound by the terms
and conditions of this Agreement and the Plan.


                                 By:



                                 Dated:









                                XOMA CORPORATION


                              RESTRICTED STOCK PLAN


               (As Restated And Amended Through October 30, 1996)



                                    ARTICLE I

                                     GENERAL


     1. PURPOSE OF THE PLAN

     This Restricted Stock Plan ("Plan") is intended to promote the interests of
XOMA Corporation (the "Corporation") by providing (i) those key employees of the
Corporation and its subsidiaries who are primarily responsible for the
management, growth and financial success of the Corporation or its subsidiaries
and (ii) those consultants who provide valuable services to the Corporation or
its subsidiaries, with the opportunity to acquire a proprietary interest, or
increase their proprietary interest, in the Corporation and thereby to encourage
such individuals to remain in the employ or service of the Corporation or its
subsidiaries.

     2. STRUCTURE OF THE PLAN

     (a) The Plan shall be divided into two separate components: the Option
Grant Program specified in Article II and the Stock Issuance Program specified
in Article III. Under the Option Grant Program, eligible individuals may be
granted options to purchase shares of the Corporation's Common Stock at a
discount of up to 15% of the fair market value of such shares on the grant date.

     (b) The Stock Issuance Program shall allow eligible individuals to acquire
shares of the Corporation's Common Stock either through direct purchases or upon
the exercise of option grants. Such shares may be purchased at a discount of up
to 15% of their fair market value on the issue date (for direct issuances) or
15% of such fair market value on the option grant date (for shares acquired upon
the exercise of granted options). The purchased shares may be issued as
fully-vested shares or as shares which are to vest over time. Issuances may be
effected. Any or all of the issued shares may be subject to a permanent right of
first refusal binding all holders of the 


<PAGE>
                                      -2-


shares to offer such shares for sale to the Corporation at a formula price prior
to any sale or other disposition to a third party. The fair market value of
shares subject to such first refusal rights shall be appropriately discounted to
reflect this non-lapse restriction.

     (c) The provisions of Articles I and IV of the Plan shall apply to both the
Option Grant Program and the Stock Issuance Program and shall accordingly govern
the interests of all individuals in the Plan.

     (d) For all purposes of the Plan, the following definitions shall be in
effect:

          (i)An individual shall be deemed to be in the Service of the
     Corporation for so long as he remains an employee of the Corporation or
     renders periodic services to the Corporation or its subsidiaries as a
     consultant, advisor or other independent service provider.

          (ii) An individual shall be deemed to be an employee of the
     Corporation for so long as he continues in the active employ of the
     Corporation or one or more of its subsidiary corporations.

          (iii) The term "subsidiary" shall mean any corporation (other than the
     Corporation) in an unbroken chain of corporations beginning with the
     Corporation, provided each of the corporations in the chain (other than the
     last corporation) owns stock possessing 50% or more of the total combined
     voting power of all classes of stock of one of the other corporations in
     such chain.

     3. ADMINISTRATION OF THE PLAN

     (a) The Plan shall be administered by the Corporation's Board of Directors
(the "Board"). The Board, however, may at any time appoint a committee
("Committee") of two (2) or more "non-employee directors" (within the meaning of
Rule 16b-3 (b)(3) of the Securities and Exchange Commission as amended in 1996
or any successor provision thereto) to administer one or more provisions of the
Plan, including the Option Grant provisions of Article II or the Stock Issuance
provisions of Article III, or to provide recommendations to the Board with
respect to the Board's administration of those provisions. It is also intended
that the non-employee directors shall also be "outside directors" (within the
meaning of Section 162(m) of the Internal Revenue Code). However, the mere fact
that a Committee 


<PAGE>
                                      -3-


member shall fail to qualify as a non-employee director or an outside director
shall not invalidate any options or shares granted by the Committee which are
otherwise validly made under the Plan. Members of the Committee shall serve for
such period of time as the Board may determine and shall be subject to removal
by the Board at any time.

     (b) The Plan Administrator (either the Board or the Committee, to the
extent the Committee has been delegated responsibility for the administration of
the Plan) shall have full power and authority (subject to the provisions of the
Plan) to establish such rules and regulations as it may deem appropriate for the
proper administration of the Plan and to make such determinations under, and
issue such interpretations of, the Plan and any outstanding option grants or
stock issuances as it may deem necessary or advisable. Decisions of the Plan
Administrator shall be final and binding on all parties who have an interest in
the Plan or any outstanding option grant or stock issuance.

     4. OPTION GRANTS AND SHARE ISSUANCES

     (a) Key employees (including officers and directors) of the Corporation (or
its subsidiaries) and consultants (other than the non-employee directors) who
provide valuable services to the Corporation (or its subsidiaries) shall be
eligible to receive share issuances under the Stock Issuance Program
("Participant") and/or option grants pursuant to the Option Grant Program
("Optionee"). Directors who are not employees of the Corporation shall not be
eligible to receive such share issuances or option grants or to participate
otherwise in the Plan.

     (b) The Committee, or the Board if no Committee is appointed pursuant to
Section 3, shall have full authority to determine, (I) with respect to the
option grants made under the Plan, the number of shares to be covered by each
grant, the time or times at which each granted option is to become exercisable
and the maximum term for which the option may remain outstanding and (II) with
respect to share issuances under the Stock Issuance Program, the number of
shares to be issued to each Participant, the vesting schedule (if any) to be
applicable to the issued shares, the consideration to be paid by the individual
for such shares and the appropriate formula price to be in effect for the
Corporation's first refusal rights.

     (c) All options granted pursuant to the Plan shall be deemed to have been
granted on the date of authorization by 


<PAGE>
                                      -4-


the Plan Administrator or at any later date specified by the Plan Administrator
at the time of such authorization. Any individual may hold more than one
outstanding option under the Plan.

     (d) The Plan Administrator shall have the absolute discretion either to
grant non-qualified options in accordance with Article II of the Plan or to
effect direct share issuances in accordance with Article III of the Plan.

     5. STOCK SUBJECT TO THE PLAN

     (a) The stock issuable under the Plan shall be shares of the Corporation's
authorized but unissued or reacquired common stock ("Common Stock"). The maximum
number of shares issuable over the term of the Plan shall not exceed 1,250,000
shares, subject to adjustment as provided in Section 5(c) of this Article I. In
no event, however, shall more than 5,150,000 shares (subject to adjustment under
Section 5(c) of this Article I) be issued in the aggregate over the term of this
Plan and the Corporation's 1981 Stock Option Plan ("1981 Plan").

     For any one individual, the number of shares for which options or stock
appreciation rights may be granted under the Option Grant Program beginning on
October 30, 1996 and ending at the expiration of the term of the Plan may not
exceed 1,000,000.

     (b) Should an option under the Plan be terminated for any reason prior to
exercise or surrender in full, the shares subject to the portion of the option
not so exercised or surrendered shall be available for subsequent option grant
or stock issuance under the Plan or for subsequent option grant under the 1981
Plan. Shares subject to an option (or portion of an option) surrendered under
the Plan in connection with a Control Acquisition (as defined in Article II,
Section 2(d)) shall not be available for subsequent option grant or stock
issuance under the Plan or for subsequent option grant under the 1981 Plan.
Shares issued under the Stock Issuance Program (whether as vested or unvested
shares) which are repurchased by the Corporation shall not be available for
subsequent reissuance under this Plan or the 1981 Plan.

     (c) If any change is made to the Common Stock issuable under the Plan by
reason of any stock dividend, stock split, combination of shares,
recapitalization or other change affecting the outstanding Common Stock as a
class without re-


<PAGE>
                                      -5-


ceipt of consideration, then appropriate adjustments shall be made to (i) the
number of shares issuable under the Plan, (ii) the number of shares issuable in
the aggregate under this Plan and the 1981 Plan and (iii) the number and/or
class of shares and the option price per share of the Common Stock subject to
each outstanding option in order to prevent the dilution or enlargement of
benefits thereunder. The adjustments determined by the Plan Administrator shall
be final, binding and conclusive.

     (d) Common Stock issuable under the Plan, whether under the Option Grant
Program or the Stock Issuance Program, may be subject to such restrictions on
transfer, repurchase rights or other restrictions as are determined by the Plan
Administrator.


                                   ARTICLE II

                              OPTION GRANT PROGRAM


     1. TERMS AND CONDITIONS OF OPTIONS

     Each option granted under the Plan shall be a non-qualified option and
shall be evidenced by a stock option agreement that complies with (or
incorporates) each of the terms and conditions of this Article II.

     (a) Option Price.

     (1) Subject to the provisions of Section (a)(2) below, the option price per
share shall be fixed by the Plan Administrator, but in no event shall it be less
than eighty-five percent (85%) of the fair market value per share of Common
Stock on the date of the option grant.

     (2) If the individual to whom the option is granted is at such time the
owner of stock (as determined under Section 425(d) of the Internal Revenue Code)
possessing 10% or more of the total combined voting power of all classes of
stock of the Corporation or any one of its subsidiary corporations ("10%
Shareholder"), then the option price per share shall not be less than one
hundred ten percent (110%) of the fair market value per share of Common Stock on
the grant date.

     (3) The option price shall become immediately due upon exercise of the
option and, subject to the provisions of Article IV, Section 2, shall be payable
in one of the fol-


<PAGE>
                                      -6-


lowing alternative forms specified below (as determined by the Plan
Administrator and set forth in the instrument evidencing the grant):

          (A) Full payment in cash or cash equivalents; or

          (B) Full payment in shares of Common Stock valued at fair market value
     on the Exercise Date (as such term is defined below) equal to the option
     price; or

          (C) Full payment in a combination of shares of Common Stock valued at
     fair market value on the Exercise Date and cash or cash equivalents, equal
     in the aggregate to the option price; or

          (D) Payment effected through a broker-dealer sale and remittance
     procedure pursuant to which the Optionee (I) shall provide irrevocable
     written instructions to the designated broker-dealer to effect the
     immediate sale of the purchased shares and remit to the Corporation, out of
     the sale proceeds, an amount equal to the aggregate option price payable
     for the purchased shares plus all applicable Federal and State income and
     employment taxes required to be withheld by the Corporation by reason of
     such purchase and (II) shall provide written directives to the Corporation
     to deliver the certificates for the purchased shares directly to such
     broker-dealer. For purposes of this subsection (a)(3), the Exercise Date is
     the date on which written notice of the exercise of the option is given to
     the Corporation. Except to the extent the sale and remittance procedure of
     clause (D) above is utilized, payment of the option price for the purchased
     shares shall accompany such notice.

     (4) For purposes of subsections (1), (2) and (3) above (and for all other
valuation purposes under the Plan), the fair market value per share of Common
Stock shall be determined in accordance with the following provisions:

          (A) If the Common Stock is not at the time listed or admitted to
     trading on any stock exchange but is traded in the over-the-counter market,
     the fair market value shall be the closing selling price per share of
     Common Stock on the date in question, as such price is reported by the
     National Association of Securities Dealers through its Nasdaq National
     Market or any successor sys-


<PAGE>
                                      -7-


     tem. If there is no reported closing selling price for the Common Stock on
     the date in question, then the closing selling price on the last preceding
     date for which such quotation exists shall be determinative of fair market
     value.

          (B) If the Common Stock is at the time listed or admitted to trading
     on any stock exchange, then the fair market value shall be the closing
     selling price per share of Common Stock on the date in question on the
     stock exchange determined by the Plan Administrator to be the primary
     market for the Common Stock, as such price is officially quoted on such
     exchange. If there is no reported sale of Common Stock on such exchange on
     the date in question, then the fair market value shall be the closing
     selling price on the exchange on the last preceding date for which such
     quotation exists.

          (C) If the Common Stock is at the time neither listed nor admitted to
     trading on any stock exchange nor traded in the over-the-counter market (or
     if the Plan Administrator determines that the value as determined pursuant
     to subsection (A) or (B) above does not reflect fair market value), then
     the Plan Administrator shall determine fair market value after taking into
     account such factors as it deems appropriate, including one or more
     independent professional appraisals.

     (b) Term and Exercise of Options; Transferability. Each option granted
under the Plan shall be exercisable at such time or times and during such period
as is determined by the Plan Administrator and set forth in the stock option
agreement evidencing such option; provided, however, that no option granted
under the Plan shall have a term in excess of ten (10) years from the grant
date.

     Options may, in the discretion of the Plan Administrator, be granted on
terms which permit their transfer or assignment to the spouse of the Optionee or
a descendent of the Optionee (any such spouse or descendent, an "Immediate
Family Member") or a corporation, partnership, limited liability company or
trust so long as all of the shareholders, partners, members or beneficiaries
thereof, as the case may be, are either the Optionee or an Immediate Family
Member of the Optionee, provided that (i) there may be no consideration for any
such transfer, (ii) the stock option agreement pursuant to which such options
are granted must expressly provide for transferability in a manner consistent
with the foregoing and 


<PAGE>
                                      -8-


(iii) subsequent transfers of transferred options will be prohibited other than
by will or the laws of descent and distribution. Following transfer, any such
options will continue to be subject to the same terms and conditions as were
applicable immediately prior to transfer, provided that for purposes of the
option agreement the term "Optionee" will refer to the transferee. The events of
termination of employment will continue to be applied with respect to the
original optionee, following which the options will be exercisable by the
transferee only to the extent, and for the periods specified, in the option
agreement.

     (c) Effect of Termination of Employment.

     (1) Should an Optionee cease to be an employee of the Corporation for any
reason (including death or permanent disability as defined in Section 22(e)(3)
of the Internal Revenue Code) while the holder of one or more outstanding
options granted to such Optionee under the Plan, then such option or options
shall in no event remain exercisable for more than a twelve (12) month period
(or such shorter period as is determined by the Plan Administrator and set forth
in the option agreement) following the date of such cessation of employee
status, and each such option shall, during such twelve (12) month or shorter
period, be exercisable only to the extent of the number of shares (if any) for
which the option is exercisable on the date of such cessation of employee
status. Under no circumstances, however, shall any such option be exercisable
after the specified expiration date of the option term. Upon the expiration of
such twelve (12) month or shorter period or (if earlier) upon the expiration of
the option term, the option shall terminate and cease to be exercisable.

     (2) Any option granted to an Optionee under the Plan and exercisable in
whole or in part on the date of the Optionee's death may be subsequently
exercised, but only to the extent of the number of shares (if any) for which the
option is exercisable on the date of the Optionee's cessation of employee
status, by the personal representative of the Optionee's estate or by the person
or persons to whom the option is transferred pursuant to subsection (b) above,
provided and only if such exercise occurs prior to the earlier of (i) the first
anniversary of the date of the Optionee's death or (ii) the specified expiration
date of the option term. Upon the occurrence of the earlier event, the option
shall terminate and cease to be exercisable.


<PAGE>
                                      -9-


     (3) If (i) the Optionee's status as an employee is terminated for cause
(including, but not limited to, any act of dishonesty, willful misconduct, fraud
or embezzlement or any unauthorized disclosure or use of confidential
information or trade secrets) or (ii) the Optionee makes or attempts to make any
unauthorized use or disclosure of confidential information or trade secrets of
the Corporation or its subsidiaries, then upon the occurrence of any such event
all outstanding options granted the Optionee under the Plan shall immediately
terminate and cease to be exercisable.

     (4) Notwithstanding subsections (1) and (2) above, the Plan Administrator
shall have the discretion to establish as a provision applicable to the exercise
of one or more options granted under the Plan that during the period of
exercisability following cessation of employee status (as provided in such
subsections), the option may be exercised not only with respect to the number of
shares for which it is exercisable at the time of the Optionee's cessation of
employee status but also with respect to one or more installments of purchasable
shares for which the option otherwise could have become exercisable had such
cessation of employee status not occurred.

     (5) If the option is granted to a consultant or other independent
contractor, then the instrument evidencing the granted option shall include
provisions comparable to subsections (1), (2) and (3) above, and may include
provisions comparable to subsection (4) above, with respect to the Optionee's
termination of Service.

     (d) Repurchase Rights. The shares of Common Stock acquired upon the
exercise of options granted under the Plan may be subject to one or more
repurchase rights of the Corporation in accordance with the following
provisions:

     (1) The Plan Administrator may in its discretion determine that it shall be
a term and condition of one or more options granted under the Plan that the
Corporation (or its assigns) shall have the right, exercisable upon the
Optionee's cessation of Service, to repurchase at the original option price any
or all unvested shares of Common Stock at the time held by such individual under
the Plan. Any such repurchase right shall be exercisable by the Corporation (or
its assigns) upon such terms and conditions (including the establishment of the
appropriate vesting schedule and other provisions for the expiration of such
right in one or more installments) 


<PAGE>
                                      -10-


as the Plan Administrator may specify in the instrument evidencing such right.

     (2) The Plan Administrator shall also have full power and authority to
provide for the automatic termination of the Corporation's outstanding
repurchase rights, in whole and in part, and thereby accelerate the vesting of
any or all purchased shares, upon the occurrence of any Corporate Transaction
specified in Article II, Section 3 below.

     (e) Shareholder Rights. An Optionee shall have no shareholder rights with
respect to any shares covered by the option until such Optionee has exercised
the option, paid the option price and been issued a stock certificate for the
purchased shares.

     2. STOCK APPRECIATION RIGHTS

     (a) One or more Optionees may, upon such terms and conditions as the Plan
Administrator may establish at the time of the option grant or at any time
thereafter, be granted the right to surrender all or part of an unexercised
option in exchange for a distribution from the Corporation in an amount equal to
the excess of (i) the fair market value (at date of surrender) of the number of
shares in which the Optionee is at the time vested under the surrendered option
or portion thereof over (ii) the aggregate option price payable for such vested
shares. No surrender of an option, however, shall be effective unless it is
approved by the Plan Administrator. If the surrender is so approved, then the
distribution to which the option holder shall accordingly become entitled under
this subsection 2(a) may be made in shares of Common Stock valued at fair market
value at date of surrender, in cash, or partly in shares and partly in cash, as
the Plan Administrator shall in its sole discretion deem appropriate.

     (b) If the surrender of an option is rejected by the Plan Administrator,
then the option holder shall retain whatever rights the option holder had under
the surrendered option (or surrendered portion thereof) on the date of surrender
and may exercise such rights at any time prior to the later of (i) the
expiration of the 5 business-day period following receipt of the rejection
notice or (ii) the last day on which the option is otherwise exercisable in
accordance with the terms of the instrument evidencing such option, but in no
event may such rights be exercised at any time after ten (10) years (or five (5)
years in the case of a 10% Shareholder) following the date of the option grant.


<PAGE>
                                      -11-


     (c) Notwithstanding the foregoing provisions of this Section 2, should
twenty-five percent (25%) or more of the Corporation's outstanding voting stock
be acquired pursuant to a tender or exchange offer (I) which is made by a person
or group of related persons other than the Corporation or a person that directly
or indirectly controls, is controlled by or is under common control with the
Corporation and (ii) which the Board does not recommend the Corporation's
shareholders to accept (a "Control Acquisition"), then each officer or director
who is subject to the short-swing profit restrictions of the Federal securities
laws shall have the right (exercisable for a period not to exceed thirty (30)
days) to surrender any or all options held by such individual under the Plan, to
the extent such options are at the time exercisable for vested shares, and
receive in exchange an appreciation distribution from the Corporation calculated
in accordance with Section 2(a). The approval of the Plan Administrator shall
not be required for such surrender, and the distribution to which such
individual shall become entitled upon such surrender shall be made entirely in
cash.

     3. SALE, MERGER, REORGANIZATION, ETC.

     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Corporation is not the
     surviving entity, except for a transaction the principal purpose of which
     is to change the State of incorporation;

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Corporation; or

          (iii) any other business combination in which fifty percent (50%) or
     more of the Corporation's outstanding voting stock is transferred to
     different holders in a single transaction or a series of related
     transactions,

then each option at the time outstanding under the Plan and not then otherwise
fully exercisable shall, immediately prior to the specified effective date for
the Corporate Transaction, become fully exercisable for up to the total number
of shares of Common Stock purchasable under such option and may be exercised for
all or any portion of the shares for which the option is so accelerated.
However, an outstanding option shall not be so accelerated if and to the extent:
(i) such option is in connection with the Corporate Transaction either to be
assumed by the 


<PAGE>
                                      -12-


successor corporation (or affiliate thereof) or be replaced with a comparable
option to purchase shares of capital stock of the successor corporation (or
affiliate thereof), such comparability to be determined by the Plan
Administrator, or (ii) the acceleration of such option would, when added to the
present value of certain other payments in the nature of compensation which
become due and payable to the Optionee in connection with the Corporate
Transaction, result in the payment to such individual of an excess parachute
payment under Section 280G(b) of the Internal Revenue Code. The existence of any
such excess parachute payment shall be determined by the Plan Administrator in
the exercise of its reasonable business judgment and on the basis of independent
tax counsel provided the Corporation.

     (b) Upon the consummation of the Corporate Transaction, all outstanding
options under the Plan shall, to the extent not previously exercised or assumed
by the successor corporation (or its affiliate), terminate and cease to be
exercisable.

     (c) If the Corporation is the surviving entity in any Corporate Transaction
or the outstanding options under the Plan are to be assumed in connection with
such Corporate Transaction, then each such continuing or assumed option shall be
appropriately adjusted immediately after such Corporate Transaction to apply and
pertain to the number and class of securities which would have been issuable to
the Optionee in consummation of the Corporate Transaction, had such option been
exercised immediately prior to the effective date of such Corporate Transaction.
Appropriate adjustments shall also be made to the option price payable per
share, provided the aggregate option price shall remain the same. In addition,
the class and number of securities available for issuance under the Plan
following the consummation of such Corporate Transaction shall be appropriately
adjusted.

     (d) The grant of options under the Plan shall not affect the right of the
Corporation to adjust, reclassify, reorganize or otherwise change its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.


<PAGE>
                                      -13-


     4. [RESERVED]


                                   ARTICLE III

                             STOCK ISSUANCE PROGRAM


     1. TERMS AND CONDITIONS OF STOCK ISSUANCES

     Shares may be issued under the Stock Issuance Program either through direct
and immediate purchases or through the exercise of options granted under the
Option Grant Program. The issued shares shall be evidenced by a Restricted Stock
Purchase Agreement ("Purchase Agreement") that complies with (or incorporates)
each of the terms and conditions of this Article III.

     (a) Share Price

     (1) The purchase price per share shall be fixed by the Plan Administrator,
but in no event shall it be less than eighty-five percent (85%) of the fair
market value per share of Common Stock on the date of issuance (or, if an option
is utilized, on the grant date of such option). However, if the individual to
whom the share issuance is made is at such time a 10% Shareholder (as defined in
Article II, Section 1(a)(2)), then the purchase price per share shall not be
less than one hundred ten percent (110%) of the fair market value per share of
Common Stock on the date of issuance (or, if an option is utilized, on the grant
date of such option). Fair market value shall be determined in accordance with
Article II, Section (1)(a)(4); provided, however, if any shares issued under the
Plan are subject to the permanent right of first refusal of the Corporation or
its assigns under subsection 1(d) below, then the fair market value shall be
appropriately adjusted to reflect the effect of such non-lapse restriction.

     (2) Shares shall be issued under the Plan for such consideration as the
Plan Administrator shall from time to time determine, provided that in no event
shall shares be issued for consideration other than:

          (A) cash or cash equivalents;

          (B) shares of Common Stock valued in accordance with Article II,
     Section 1(a)(4);


<PAGE>
                                      -14-


          (C) a promissory note of the Participant payable to the Corporation's
     order, which may be subject to cancellation by the Corporation in whole or
     in part upon such terms or conditions as the Plan Administrator shall
     specify; or

          (D) payment effected through a broker-dealer sale and remittance
     procedure pursuant to which the Participant (I) shall provide irrevocable
     written instructions to the designated broker-dealer to effect the
     immediate sale of the purchased shares and remit to the Corporation, out of
     the sale proceeds, an amount equal to the aggregate purchase price payable
     for the purchased shares plus all applicable Federal and State income and
     employment taxes required to be withheld by the Corporation by reason of
     such purchase and (II) shall provide written directives to the Corporation
     to deliver the certificates for the purchased shares directly to such
     broker-dealer.

     (b) Vesting Schedule

     (1) The interest of a Participant in the shares of Common Stock issued to
him under the Plan may, in the absolute discretion of the Plan Administrator, be
fully and immediately vested upon issuance or may vest in one or more
installments in accordance with the vesting provisions of subsection (b)(4).
Except as otherwise provided in subsection (b)(3), the Participant may not
transfer any of the Common Stock in which he does not have a vested interest;
accordingly, all unvested shares issued to him under the Plan shall bear the
restrictive legend specified in subsection (c)(1), until such legend is removed
in accordance with subsection (c)(2). The Participant, however, shall have all
the rights of a shareholder with respect to the shares of Common Stock issued to
him hereunder, whether or not his interest in such shares is at the time vested.
Accordingly, the Participant shall have the right to vote such shares and to
receive any cash dividends or other distributions paid or made with respect to
such shares. Any new, additional or different shares of stock or other property
(including money paid other than as a regular cash dividend) which the holder of
unvested Common Stock may have the right to receive by reason of a stock
dividend, stock split or reclassification of Common Stock or by reason of a
merger, consolidation, reorganization or liquidation shall be issued to him,
subject to (i) the same vesting requirements under subsection (b)(4) applicable
to his unvested Common Stock and (ii) such escrow arrangements as the Plan
Administrator shall deem appropriate.


<PAGE>
                                      -15-


     (2) As used in this Article III, the term "transfer" shall include (without
limitation) any sale, pledge, encumbrance, gift or other disposition of such
shares. However, the Participant shall have the right to make a gift of one or
more shares acquired under the Stock Issuance Program, whether vested or
unvested and whether or not subject to the subsection (d)(1) right of first
refusal, to his spouse, parents or children or to a trust established for such
spouse, parents or children, provided the donee of such shares delivers to the
Corporation a written agreement to be bound by all the provisions of the Plan
and other instruments executed by the Participant to evidence his prior
acquisition of the gifted shares. Any gift made in accordance with the foregoing
limitations shall not trigger the exercise of the Corporation's repurchase
rights under subsection (b)(3) or the Corporation's first refusal rights under
subsection (d)(1).

     (3) In the event a Participant should, while his interest in the Common
Stock remains unvested, (i) attempt to transfer (other than by way of a
permissible gift under subsection (b)(2)) any of the unvested Common Stock or
any interest therein or (ii) cease to remain in Service for any reason
whatsoever, then the Corporation shall have the right to repurchase any or all
of the unvested shares at a price equal to the lesser of (i) the original
purchase price paid by the Participant or, if such shares are subject to the
Corporation's permanent first refusal right under subsection (d)(1), (ii) the
fair market value of such shares appropriately discounted to reflect the
Corporation's right of first refusal, and the Participant shall thereafter have
no further shareholder rights with respect to the repurchased shares.

     (4) Any shares of Common Stock issued under the Stock Issuance Program
which are not vested at the time of such issuance shall vest in one or more
installments thereafter. The elements of the vesting schedule, namely the number
of installments in which the shares are to vest, the interval or intervals (if
any) which are to lapse between installments and the effect which death,
disability or any other event designated by the Plan Administrator is to have
upon the vesting schedule, shall be determined by the Plan Administrator and
shall be specified in the Purchase Agreement executed by the Corporation and the
Participant at the time of issuance of the unvested shares.

     (5) The Plan Administrator may in its discretion elect not to exercise, in
whole or in part, its repurchase rights with respect to any unvested Common
Stock or other as-


<PAGE>
                                      -16-


sets which would otherwise at the time be subject to repurchase
pursuant to the provisions of subsection (b)(3). Such an election shall result
in the immediate vesting of the Participant's interest in the shares of Common
Stock as to which the election applies.

     (c) Stock Legends

     (1) Each certificate representing unvested shares of Common Stock (or other
securities) issued under the Plan shall bear a restrictive legend substantially
as follows:

                  "The securities represented by this certificate are subject to
         repurchase by the Corporation pursuant to the provisions of the
         Restricted Stock Purchase Agreement between the Corporation and the
         registered holder of the securities (or his predecessor in interest).
         Such agreement grants certain repurchase rights to the Corporation in
         the event the registered holder (or his predecessor in interest)
         terminates his employment or service with the Corporation. A copy of
         such agreement is on file at the principal office of the Corporation."

     (2) As the interest of the Participant vests with respect to any stock
certificate representing shares acquired under the Stock Issuance Program, the
Corporation shall, upon the Participant's delivery of such certificate during
the period or periods designated each year by the Plan Administrator, issue a
new certificate for the vested shares without the restrictive legend of
subsection (c)(1) and a second certificate for the balance of the shares with
such legend. If the Corporation repurchases any unvested shares of the
Participant pursuant to the provisions of subsection (b)(3), the Corporation
shall at the time the repurchase is effected deliver a new certificate, without
the restrictive legend of subsection (c)(1), representing the number of shares
(if any) in which the Participant is vested and which are accordingly no longer
subject to repurchase by the Corporation pursuant to the provisions of
subsection (b)(3).

     (d) Permanent Right of First Refusal

     (1) Any and all shares issued under the Stock Issuance Program may, in the
discretion of the Plan Administrator, be subject to a permanent right of first
refusal exercisable by the Corporation or its assigns. Should shares subject to
such restriction be issued, then the Participant (and each 


<PAGE>
                                      -17-


successor in interest or transferee of the shares) must, prior to any subsequent
sale or other transfer of the shares for value, first offer to sell the shares
to the Corporation or its assigns at a price determined in accordance with the
following formula:

          X = M - D, where

          X is the price at which the Corporation or its assigns may repurchase
          the shares,

          M is the fair market value of the shares on the date of repurchase,
          determined in accordance with the provisions of Article II, Section
          1(a)(4), without regard to the Corporation's permanent right of first
          refusal, and

          D is the appropriate price differential determined by the Plan
          Administrator in its sole discretion at the time the shares are issued
          and set forth in the written instrument evidencing such right.

     (2) Each stock certificate representing shares subject to the subsection
(d)(1) right of first refusal shall be appropriately legended to disclose the
perpetual existence of such right, and all transferees of the shares shall
accordingly take the shares subject to the terms and provisions of the
Corporation's permanent right of first refusal.

     (3) The remaining terms and provisions of the permanent right of first
refusal shall be determined by the Plan Administrator in its discretion and
specified in the written instrument evidencing such right.

     (4) The Plan Administrator may, at any time in its sole discretion, cancel
(upon such terms and conditions as it deems appropriate) the Corporation's
rights of first refusal with respect to one or more shares issued with such
restrictions under the Share Issuance Program.



<PAGE>
                                      -18-


                                   ARTICLE IV

                                  MISCELLANEOUS


     1. INVESTMENT PURPOSE

     If necessary or advisable to comply with applicable Federal or State
securities laws, any option granted, or shares issued, under the Plan may be
granted or issued on the condition that the Optionee or Participant agrees that
the shares of Common Stock purchased thereunder are for investment purposes only
and not for resale or distribution and that such shares shall be disposed of
only in accordance with such laws. As a condition to issuance of any shares
purchased upon the exercise of any option granted, or shares issued, pursuant to
the Plan, the Optionee or Participant, or his executor, administrator, heir,
legatee or transferee (as the case may be) receiving such shares may be required
to deliver to the Corporation an instrument, in form and substance satisfactory
to the Corporation and its counsel, implementing such agreement. Any such
condition may be eliminated by the Plan Administrator if the Plan Administrator
determines it is no longer necessary or advisable.

     2. LOANS OR GUARANTEE OF LOANS

     The Plan Administrator may, in its discretion, assist any Optionee or
Participant (including an Optionee or Participant who is an officer or director
of the Corporation) in the exercise of one or more options granted to such
Optionee under the Article II Option Grant Program or the purchase of one or
more shares issued to such Participant under the Article III Stock Issuance
Program, including the satisfaction of any Federal and State income and
employment tax obligations arising therefrom, by (i) authorizing the extension
of a loan from the Corporation to such Optionee or Participant, (ii) permitting
the Optionee or Participant to pay the option price or purchase price for the
purchased Common Stock in installments over a period of years, or (iii)
authorizing a guarantee by the Corporation of a third-party loan to the Optionee
or Participant. The terms of any loan, installment method of payment or
guarantee (including the interest rate and terms of repayment) shall be upon
such terms as the Plan Administrator specifies in the stock option agreement or
restricted stock purchase agreement. Such loans, installment payments and
guarantees may be granted with or without security or collateral, but the
maximum credit available to the Optionee or Participant may not exceed (A) the
aggregate option price or purchase price for the shares (less 


<PAGE>
                                      -19-


their par value, which must in all events be paid in cash) plus (B) any Federal
and State income and employment tax liability incurred by the Optionee or
Participant in connection with such exercise or purchase.

     3. AMENDMENT OF THE PLAN AND AWARDS

     (a) The Board has complete and exclusive power and authority to amend or
modify the Plan (or any component thereof) in any or all respects whatsoever;
provided, however, that no such amendment or modification may adversely affect
rights and obligations of an option holder with respect to options at the time
outstanding under the Plan, nor adversely affect the rights of any Participant
with respect to Common Stock issued under the Plan prior to such action, unless
the Optionee or Participant consents to such amendment. In addition, the Board
may not, without the approval of the Corporation's shareholders, amend the Plan
to (i) increase the maximum number of shares issuable under the Plan (except for
permissible adjustments under Article I, Section 5(c)), (ii) materially increase
the benefits accruing to individuals who participate in the Plan, or (iii)
materially modify the eligibility requirements for participation in the Plan.

     (b) Options may be granted under the Plan to purchase shares of Common
Stock in excess of the number of shares then available for issuance under the
Plan, provided (i) an amendment to increase the maximum number of shares
issuable under the Plan is adopted by the Board prior to the initial grant of
any such option and is thereafter submitted to the Corporation's shareholders
for approval and (ii) each option so granted is not to become exercisable, in
whole or in part, at any time prior to the obtaining of such shareholder
approval.

     4. EFFECTIVE DATE AND TERM OF PLAN

     (a) The Plan as initially implemented became effective on December 23,
1983, upon the issuance of 92,000 shares of Common Stock subject to the
Corporation's permanent rights refusal under Article III, Section 1(d). The Plan
was restated in April 1987 and approved by the Corporation's shareholders at the
1987 Annual Meeting. At the 1989 Annual Meeting, the Corporation's shareholders
approved an increase in the number of shares of Common Stock issuable over the
term of the Plan from 200,000 shares to 300,000 shares. The Plan was restated in
1990 and approved in 1991 to extend its term to December 15, 2003 and to
increase the number of shares of Common Stock issuable over the term of the Plan
to 550,000 shares, again in 1992 


<PAGE>
                                      -20-


to increase the number of shares to 1,000,000 shares, and again in 1996 to
increase the number of shares to 1,250,000 shares. This new restatement of the
Plan was adopted by the Board on October 30, 1996 and was approved by the
Corporation's shareholders at the 1997 Annual Meeting.

     (b) The provisions of this restated and amended Plan shall apply only to
option grants and share issuances effected under the Plan from and after the
October 30, 1996 effective date. All option grants and share issuances effected
under the Plan prior to such effective date shall continue to be governed by the
terms and conditions of the Plan (and the respective instruments evidencing each
such grant or issuance) as in effect on the date the option grant or share
issuance was previously made, and nothing in this October 30, 1996 restatement
shall be deemed to affect or otherwise modify the rights or obligations of the
holders of such option grants or share issuances with respect to the shares of
Common Stock subject thereto.

     (c) Unless sooner terminated in accordance with Section 3 of Article II,
the Plan shall terminate upon the earlier of (i) December 15, 2003 or (ii) the
date on which all shares available for issuance under the Plan have been issued
or cancelled pursuant to the exercise or surrender of options granted under
Article II or pursuant to the issuance of shares under Article III. If the date
of termination is determined under clause (i) above, then all options
outstanding on such date under Article II and all shares issued and outstanding
on such date under Article III shall not be affected by the termination of the
Plan and will thereafter continue to have force and effect in accordance with
the provisions of the stock option agreements evidencing such Article II options
and the stock purchase agreements evidencing the issuance of such Article III
shares.

     5. USE OF PROCEEDS

     Any cash proceeds received by the Corporation from the issuance of shares
of Common Stock hereunder shall be used for general corporate purposes.

     6. WITHHOLDING

     The Corporation's obligation to deliver shares upon the exercise or
surrender of any options granted under Article II or upon the purchase of any
shares issued under Article III shall be subject to the satisfaction of all
applicable Federal, 


<PAGE>
                                      -21-


State and local income and employment tax withholding requirements.

     7. REGULATORY APPROVALS

     The implementation of the Plan, the granting of any option under the Option
Grant Program, the issuance of any shares under the Stock Issuance Program, and
the issuance of Common Stock upon the exercise or surrender of the option grants
made hereunder shall be subject to the Corporation's procurement of all
approvals and permits required by regulatory authorities having jurisdiction
over the Plan, the options granted under it, and the Common Stock issued
pursuant to it.




                      Non-Qualified Stock Option Agreement

                           Under the XOMA Corporation

                              Restricted Stock Plan



(A)        Optionee:                     (E)         Payroll Number:

(B)        Grant Date:                   (F)         Expiration Date:

(C)        Shares:                       (G)         Exercise Price:

(D)        Share Installments:           (H)         Option Type:
           shares -                                  Non-Qualified Stock Option
           shares -
           shares -
           shares -
           shares

     XOMA Corporation (the "Company") has granted you a non-qualified option to
purchase the number of shares of Common Stock shown in item (C) above (the
"Optioned Shares") at the Exercise Price per share shown in item (G) above. This
option is subject to the terms of the Company's Restricted Stock Plan, as
amended and restated through October 30, 1996 (the "Plan") and to the terms and
conditions set forth in this Non-Qualified Stock Option Agreement Under the XOMA
Corporation Restricted Stock Plan (the "Agreement").

     The details of your option are as follows:

     1. Term; Transfer. The term of this option commences on the Grant Date
shown in item (B) above and, except as provided in Section 3 and Subsection 5(a)
hereof, expires at the close of business on the Expiration Date shown in item
(F) above, which is 10 years from the Grant Date.

     This option may be transferred or assigned to your spouse or descendent
(any such spouse or descendent, your "Immediate Family Member") or a
corporation, partnership, limited liability company or trust so long as all of
the shareholders, partners, members or beneficiaries thereof, as the case may
be, are either you or your Immediate Family Member, provided that (i) there may
be no consideration for any such transfer and 


<PAGE>
                                      -2-


(ii) subsequent transfers of the transferred option will be prohibited other
than by will or the laws of descent and distribution. Following transfer, the
option will continue to be subject to the same terms and conditions as were
applicable immediately prior to transfer, provided that for purposes of this
Agreement any references to "you" will refer to the transferee. The events of
termination of employment will continue to be applied with respect to you,
following which the option will be exercisable by the transferee only to the
extent, and for the periods specified, in this Agreement.

     2. Exercise Schedule. Provided that you remain an employee of the Company
(as determined in accordance with Subsection 3(e) hereof), the option granted
herein will become exercisable in accordance with the following schedule:

     (a) This option will become exercisable with respect to 20% of the Optioned
Shares after the expiration of one year from the Grant Date;

     (b) This option will become exercisable with respect to an additional 20%
of the Optioned Shares after the expiration of two years from the Grant Date;

     (c) This option will become exercisable with respect to an additional 20%
of the Optioned Shares three years from the Grant Date;

     (d) This option will become exercisable with respect to an additional 20%
of the Optioned Shares four years from the Grant Date; and,

     (e) This option will become exercisable with respect to the remaining 20%
of the Optioned Shares after the expiration of five years from the Grant Date.

     Exercisable installments may be exercised in whole or in part in increments
of 25 or more shares and, to the extent not exercised, will accumulate and be
exercisable at any time on or before the Expiration Date or sooner termination
of the option term.

     3. Termination of Option Term. The option term specified in Section 1 will
terminate (and this option will cease to be exercisable) prior to the Expiration
Date should one of the following provisions become applicable:


<PAGE>
                                      -3-


     (a) Except as otherwise provided in Subsections (b), (c) and (d) below, if
you cease to be an employee of the Company at any time during the option term,
then the period for exercising this option will be limited to the three-month
period commencing with the date of such cessation of employee status; provided
that in no event will this option be exercisable at any time after the
Expiration Date. During such limited period of exercisability, this option may
not be exercised for more than the number of Optioned Shares (if any) for which
it is exercisable at the date of your cessation of employee status. Upon the
expiration of such limited period of exercisability or (if earlier) upon the
Expiration Date, this option will terminate and cease to be outstanding.

     (b) If you die while this option is outstanding, then the personal
representative of your estate or the person or persons to whom the option is
transferred pursuant to your will, in accordance with the laws of descent and
distribution, or pursuant to Section 1 above, will have the right to exercise
this option, but only with respect to the number of Optioned Shares (if any) for
which it is exercisable at the date of your death. Such right will lapse, and
this option will cease to be exercisable, upon the earlier of (i) the expiration
of the one-year period measured from the date of your death or (ii) the
specified Expiration Date of the option term.

     (c) If you become permanently disabled and cease by reason thereof to be an
employee of the Company at any time during the option term, then you will have a
period of twelve months (commencing with the date of such cessation of employee
status) during which to exercise this option; provided, however, that in no
event shall this option be exercisable at any time after the Expiration Date.
During such limited period of exercisability, this option may not be exercised
for more than the number of Optioned Shares (if any) for which this option is
exercisable at the date of your cessation of employee status. Upon the
expiration of such limited period of exercisability or (if earlier) upon the
Expiration Date, this option will terminate and cease to be outstanding. You
will be deemed to be permanently disabled if you are, by reason of any medically
determinable physical or mental impairment expected to result in death or to be
of continuous duration of not less than twelve consecutive months or more,
unable to perform your usual duties for the Company or its subsidiaries.

     (d) Should (i) your status as an employee be terminated for cause
(including, but not limited to, any act of dishonesty, willful misconduct, fraud
or embezzlement or any unau-


<PAGE>
                                      -4-


thorized disclosure or use of confidential information or trade secrets), or
(ii) you make or attempt to make any unauthorized use or disclosure of
confidential information or trade secrets of the Company or its subsidiaries,
then in any such event this option will terminate and cease to be exercisable
immediately upon the date of such termination of employee status or such
unauthorized use or disclosure of confidential or secret information or attempt
thereat.

     (e) For purposes of this Agreement, you will be deemed to be an employee of
the Company for so long as you remain in the employ of the Company or one or
more of its subsidiaries. A corporation will be deemed to be a subsidiary of the
Company if it is a member of an unbroken chain of corporations beginning with
the Company, provided that each such corporation in the chain (other than the
last corporation) owns, at the time of determination, stock possessing 50% or
more of the total combined voting power of all classes of stock in one of the
other corporations in such chain.

     4. Adjustment in Option Shares.

     (a) If any change is made to the Common Stock issuable under the Plan,
whether by reason of any stock dividend, stock split, combination of shares,
recapitalization or other change affecting the outstanding Common Stock as a
class without receipt of consideration, then appropriate adjustments will be
made to (i) the total number of Optioned Shares subject to this option and (ii)
the Exercise Price payable per share, in order to reflect such change and
thereby preclude the dilution or enlargement of benefits under this Agreement.
The adjustments determined by the plan administrator (the "Plan Administrator")
will be final, binding and conclusive.

     (b) If the Company is the surviving entity in any merger or other business
combination, then this option, if outstanding under the Plan immediately after
such merger or other business combination, will be appropriately adjusted to
apply and pertain to the number and class of securities which the holder of the
same number of shares of Common Stock as are subject to this option immediately
prior to such merger or other business combination would have been entitled to
receive in the consummation of such merger or other business combination, and an
appropriate adjustment will be made to the Exercise Price payable per share,
provided the aggregate Exercise Price payable hereunder will remain the same.

     5. Corporate Transaction.


<PAGE>
                                      -5-


     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Company is not the surviving
     entity, except for a transaction the principal purpose of which is to
     change the State of the Company's incorporation,

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Company, or

          (iii) any other corporate reorganization or business combination in
     which fifty percent (50%) or more of the Company's outstanding voting stock
     is transferred to different holders in a single transaction or a series of
     related transactions,

then the exercisability of this option will automatically be accelerated so that
such option may be exercised simultaneously with consummation of such Corporate
Transaction for any or all of the Optioned Shares. No such acceleration of this
option will occur, however, if and to the extent: (x) the terms of the agreement
provide as a prerequisite to the consummation of such Corporate Transaction that
outstanding options under the Plan (including this option) are to be assumed by
the successor corporation or parent thereof or are to be replaced with the
comparable options to purchase shares of capital stock of the successor
corporation or parent thereof, such comparability to be determined by the Plan
Administrator, or (y) the acceleration of this option would, when added to the
present value of certain other payments in the nature of compensation which
become due and payable to you in connection with the Corporate Transaction,
result in the payment to you of excess parachute payments under Section 280G(b)
of the Internal Revenue Code. The existence of such excess parachute payments
will be determined by the Plan Administrator in the exercise of its reasonable
business judgment and on the basis of tax counsel provided to the Company.
Immediately following consummation of the Corporate Transaction, this option
will, to the extent not previously exercised or assumed by the successor
corporation or its parent company, terminate and cease to be exercisable.

     (b) The Plan Administrator will use its best efforts to provide you with
written notice of a Corporate Transaction at least ten business days prior to
the effective date.

     (c) This Agreement will not in any way affect the right of the Company to
adjust, reclassify, reorganize or otherwise 


<PAGE>
                                      -6-


make changes in its capital or business structure or to merge, consolidate,
dissolve, liquidate or sell or transfer all or any part of its business or
assets.

     6. Privilege of Stock Ownership. The holder of this option will not have
any rights of a shareholder with respect to the Optioned Shares until such
individual has exercised the option, paid the Exercise Price and been issued a
stock certificate for the purchased shares.

     7. Manner of Exercising Option.

     (a) In order to exercise this option with respect to all or any part of the
Optioned Shares for which this option is at the time exercisable, you (or in the
case of exercise after your death, your executor, administrator, heir, legatee
or transferee as the case may be) must take the following actions:

          (i) Provide the Secretary of the Company with written notice of such
     exercise, specifying the number of Optioned Shares with respect to which
     the option is being exercised.

          (ii) Pay the Exercise Price for the purchased Optioned Shares in one
     or more of the following alternative forms: (A) full payment in cash or by
     check payable to the Company's order; (B) full payment in shares of Common
     Stock of the Company valued at fair market value on the exercise date (as
     such terms are defined below); (C) full payment in combination of shares of
     Common Stock of the Company valued at fair market value on the exercise
     date and cash or check payable to the Company's order; (D) payment effected
     through a broker-dealer sale and remittance procedure pursuant to which you
     (I) will provide irrevocable written instructions to the designated
     broker-dealer to effect the immediate sale of the purchased shares and
     remit to the Company, out of the sale proceeds, an amount equal to the
     aggregate Exercise Price payable for the purchased shares plus all
     applicable Federal and State income and employment taxes required to be
     withheld by the Company by reason of such purchase and (II) will provide
     written directives to the Company to deliver the certificates for the
     purchased shares directly to such broker-dealer; or, to the extent the Plan
     Administrator specifically authorizes such method of payment at the time of
     exercise, (E) payment by a full-recourse promissory note. Any such
     promissory note authorized by the Plan Administrator will be substantially
     in the form approved by the 


<PAGE>
                                      -7-


     Plan Administrator, will bear interest at the minimum per annum rate
     necessary to avoid the imputation of interest income to the Company and
     compensation income to you under the Federal tax laws and will become due
     in full (in one or more consecutive annual installments measured from the
     execution date of the note) not later than the Expiration Date of this
     option. Payment of the note will be secured by the pledge of the purchased
     shares, and the pledged shares will be released only as the note is paid.

          (iii) Furnish to the Company appropriate documentation that the person
     or persons exercising the option, if other than you, have the right to
     exercise this option.

     (b) For purposes of Subsection 7(a) hereof, the fair market value per share
of Common Stock on any relevant date will be determined in accordance with
Subsections (i) through (iii) below, and the exercise date will be the date on
which you exercise this option in compliance with the provisions of Subsection
7(a).

          (i) If the Common Stock is not listed or admitted to trading on any
     stock exchange on the date in question, but is traded in the
     over-the-counter market, the fair market value will be the closing selling
     price per share of such stock on such date, as such price is reported by
     the National Association of Securities Dealers through its Nasdaq National
     Market. If there is no reported closing selling price of the stock on the
     date in question then the closing selling price on the last preceding date
     for which such quotation exists will be determinative of fair market value.

          (ii) If the Common Stock is listed or admitted to trading on any stock
     exchange on the date in question, the fair market value will be the closing
     selling price per share of such stock on such date on the stock exchange
     determined by the Plan Administrator to be the primary market for such
     stock, as such price is officially quoted on such exchange. If there is no
     reported closing selling price of such stock on such exchange on the date
     in question, the fair market value will be the closing selling price on the
     exchange on the last preceding date for which such quotation exists.

          (iii) If the Common Stock is neither listed nor admitted to trading on
     any stock exchange nor traded in the over-the-counter market on the date in
     question or if the 


<PAGE>
                                      -8-


     Plan Administrator determines that the quotations under Subsections (i) or
     (ii) above do not accurately reflect the fair market value of such stock,
     the fair market value will be determined by the Plan Administrator after
     taking into account such factors as the Plan Administrator may deem
     appropriate, including one or more independent professional appraisals.

     (c) In no event may this option be exercised for any fractional share.

     8. Compliance with Laws and Regulations.

     (a) The exercise of this option and the issuance of Optioned Shares upon
such exercise will be subject to compliance by the Company and by you with all
applicable requirements of law relating thereto and with all applicable
regulations of any stock exchange on which shares of the Company's Common Stock
may be listed at the time of such exercise and issuance.

     (b) In connection with the exercise of this option, you will execute and
deliver to the Company such representations in writing as may be requested by
the Company in order for it to comply with the applicable requirements of
Federal and State securities laws.

     9. Restrictive Legends. If and to the extent any Optioned Shares acquired
under this option are not registered under the Securities Act of 1933, the stock
certificates for such Optioned Shares will be endorsed with restrictive legends,
including (without limitation) the following:

         "The Shares represented by this certificate have not been registered
         under the Securities Act of 1933. The shares have been acquired for
         investment and may not be sold or offered for sale in the absence of
         (a) an effective registration statement for the shares under such Act,
         (b) a 'no action' letter of the Securities and Exchange Commission with
         respect to such sale or offer, or (c) an opinion of counsel to the
         Company that registration under such Act is not required with respect
         to such sale or offer."

     10. Successors and Assigns. Except to the extent otherwise provided in
Section 1 and Subsection 5(a), the provisions of this Agreement will inure to
the benefit of, and be binding upon your successors, administrators, heirs,
legal representa-


<PAGE>
                                      -9-


tives and assigns and the successors and assigns of the Company.

     11. Liability of the Company.

     (a) If the Optioned Shares covered by this Agreement exceed, as of the
Grant Date, the number of shares of Common Stock which may without shareholder
approval be issued under the Plan, then this option will be void with respect to
such excess shares unless shareholder approval of an amendment sufficiently
increasing the number of shares of Common Stock issuable under the Plan is
obtained in accordance with the provisions of the Plan.

     (b) The inability of the Company to obtain approval from any regulatory
body having authority deemed by the Company to be necessary to the lawful
issuance and sale of any Common Stock pursuant to this option will relieve the
Company of any liability in respect of the non-issuance or sale of such stock as
to which such approval will not have been obtained.

     12. No Employment Contract. Nothing in this Agreement or in the Plan will
confer upon you any right to continue in the employ of the Company for any
period of time or interfere with or otherwise restrict in any way the rights of
the Company (or any subsidiary of the Company employing you) or you, which
rights are hereby expressly reserved by each, to terminate your employee status,
at any time for any reason whatsoever, with or without cause.

     13. Notices. Any notice required to be given or delivered to the Company
under the terms of this Agreement will be in writing and addressed to the
Company in care of its Secretary at its corporate offices. Any notice required
to be given or delivered to you will be in writing and addressed to you at the
address indicated below your signature line herein. All notices will be deemed
to be given or delivered upon personal delivery or upon deposit in the U.S.
mail, postage prepaid and properly addressed to the party to be notified.

     14. Construction. This Agreement and the option evidenced hereby are made
and granted pursuant to the Plan and are in all respects limited by and subject
to the express terms and provisions of the Plan. Any dispute regarding the
interpretation of this Agreement will be submitted to the Plan Administrator for
resolution. The decision of the Plan Administrator will be final, binding and
conclusive. Questions regarding 


<PAGE>
                                      -10-


this option or the Plan should be referred to the Paralegal Assistant in the
Legal Department.

     15. Governing Law. The interpretation, performance, and enforcement of this
Agreement will be governed by the laws of the State of California.

     16. Tax Arrangements. You hereby agree to make appropriate arrangements
with the Company or subsidiary thereof by which you are employed for the
satisfaction of all Federal, State or local income tax withholding requirements
and Federal social security employee tax requirements applicable to the exercise
of this option.

                                XOMA CORPORATION



                                By:  __________________________
                                     John L. Castello
                                     Chairman of the Board,
                                     President & Chief
                                       Executive Officer

                                Dated:  _______________________


     I hereby agree to be bound by the terms and conditions of this Agreement
and the Plan.

                                By:  __________________________


                                Dated:  _______________________




     If the optionee resides in California or another community property
jurisdiction, I, as the optionee's spouse, also agree to be bound by the terms
and conditions of this Agreement and the Plan.

                                 By:  __________________________


                                 Dated:_________________________






                                                                        EMPLOYEE

                                                            REPURCHASE RIGHT AND
                                                              PERMANENT RIGHT OF
                                                                   FIRST REFUSAL


                                XOMA CORPORATION


                              RESTRICTED STOCK PLAN
                       RESTRICTED STOCK PURCHASE AGREEMENT


     Agreement made as of the day of , 19 by and among XOMA Corporation, a
Delaware corporation (the "Corporation"), ,a key employee (the "Purchaser") of
the Corporation and a participant in the Corporation's Restricted Stock Plan
(the "Plan"), and __________, the Purchaser's spouse.


I.       PURCHASE OF SHARES


     1.1 Purchase. The Purchaser hereby purchases, and the Corporation hereby
sells to the Purchaser, __________ shares of the Corporation's common stock (the
"Purchased Shares") at a purchase price of $ per share (the "Purchase Price")
pursuant to the provisions of the Plan.

     1.2 Payment. Concurrently with the execution of this Agreement, the
Purchaser shall deliver to the Corporation the full amount of the Purchase
Price, payable (i) in cash or cash equivalent; (ii) in shares of common stock
held by the Purchaser; (iii) payment effected through a broker-dealer sale and
remittance procedure pursuant to which the Purchaser (A) shall provide
irrevocable written instructions to the designated broker-dealer to effect the
immediate sale of the Purchased Shares and remit to the Corporation, out of the
sale proceeds, an amount equal to the aggregate Purchase Price plus all
applicable Federal and State income and employment taxes required to be withheld
by the Corporation by reason of such purchase and (B) shall provide written
directives to the Corporation to deliver the certificates for the Purchased
Shares directly to such broker-dealer; or (iv) by promissory note authorized by
the Plan Administrator and payable to the Corporation's order.


<PAGE>
                                      -2-


     1.3 Stockholder Rights. As soon as reasonably practicable following receipt
of the Section 1.2 payment, the Corporation shall issue a stock certificate for
the Purchased Shares to the Purchaser. Upon such issuance and until such time as
the Corporation actually exercises its repurchase rights under this Agreement,
Purchaser (or any successor in interest) shall have all the rights of a
stockholder (including voting and dividend rights) with respect to the Purchased
Shares, subject, however, to the transfer restrictions of Article II.


II.      TRANSFER RESTRICTIONS


     2.1 Restriction on Transfer. Purchaser shall not transfer, assign, encumber
or otherwise dispose of any of the Purchased Shares which are subject to the
Corporation's Repurchase Right under Article III or the Corporation's First
Refusal Right under Article IV. Such restrictions on transfer, however, shall
not be applicable to (i) a gratuitous transfer of the Purchased Shares made to
the Purchaser's spouse or issue, including adopted children, or to a trust for
the exclusive benefit of the Purchaser or the Purchaser's spouse or issue, (ii)
a transfer of title to the Purchased Shares effected pursuant to the Purchaser's
will or the laws of interstate succession, or (iii) a transfer to the
Corporation in pledge as security for any purchase-money indebtedness incurred
in the acquisition of the Purchased Shares.

     2.2 Transferee Obligations. Each person (other than the Corporation) to
whom the Purchased Shares are transferred by means of one of the permitted
transfers specified in Section 2.1 must, as a condition precedent to the
validity of such transfer, acknowledge in writing to the Corporation that such
person is bound by the provisions of this Agreement and that the transferred
shares are subject to both the Corporation's Repurchase Right and the
Corporation's First Refusal Right created hereunder, to the same extent such
shares would be so subject if retained by the Purchaser.

     2.3 Definition of Owner. For purposes of Articles III and IV, the term
"Owner" shall include the Purchaser and all subsequent holders of the Purchased
Shares who derive their chain of ownership through a permitted transfer from the
Purchaser in accordance with Section 2.1.



<PAGE>
                                      -3-


III.     REPURCHASE RIGHT


     3.1 Grant. The Corporation is hereby granted the right (the "Repurchase
Right"), exercisable at any time during the sixty (60)-day period following the
date the Purchaser ceases for any reason to be an Employee of the Corporation or
(if later) during the sixty (60)-day period following the date of this
Agreement, to repurchase at the lesser of (i) the Purchase Price or (ii) the
fair market value of the Purchased Shares (adjusted to reflect the formula price
restrictions of Section 4.4) any or all of the Purchased Shares in which the
Purchaser has not acquired a vested interest in accordance with the vesting
provisions of Section 3.3 (such shares to be hereinafter called the "Unvested
Shares"). For purposes of this Agreement, the Purchaser shall be deemed to be an
Employee of the Corporation for so long as the Purchaser remains an active
employee of the Corporation or any subsidiary corporation (as defined in Section
5.4).

     3.2 Exercise of the Repurchase Right. The Repurchase Right shall be
exercisable by written notice delivered to the Owner of the Unvested Shares
prior to the expiration of the sixty (60)-day period specified in Section 3.1.
The notice shall indicate the number of Unvested Shares to be repurchased and
the date on which the repurchase is to be effected, such date to be not more
than thirty (30) days after the date of notice. Prior to the close of business
on the date specified for the repurchase, the Owner shall deliver to the
Secretary of the Corporation the certificates representing the Unvested Shares
to be repurchased, each certificate to be properly endorsed for transfer. The
Corporation shall concurrently with the receipt of such stock certificates pay
to the Owner, in cash or cash equivalents (including the cancellation of any
outstanding purchase-money indebtedness), an amount equal to the Purchase Price
previously paid for the Unvested Shares which are to be repurchased. Such
Unvested Shares shall thereupon be canceled and cease to be issued and
outstanding shares of the Corporation's common stock.

     3.3 Termination of the Repurchase Right. The Repurchase Right shall
terminate, and the Owner shall accordingly vest in the Purchased Shares, in
accordance with the following provisions:

     (a) The Repurchase Right shall terminate with respect to any Unvested
Shares for which it is not timely exercised under Section 3.2.


<PAGE>
                                      -4-


     (b) The Repurchase Right shall terminate, and cease to be exercisable, with
respect to any and all Purchased Shares in which the Purchaser vests in
accordance with the schedule below. Accordingly, provided the Purchaser
continues to be an Employee of the Corporation, the Purchaser shall acquire a
vested interest in, and the Repurchase Right shall lapse with respect to, one or
more Purchased Shares in accordance with the following vesting provisions:

     (i) The Purchaser shall not acquire any vested interest in, nor shall the
Repurchase Right lapse with respect to, any Purchased Shares during the initial
__________ (_) calendar month period measured from the Grant Date of the Option.

     (ii) Upon the expiration of such initial ________ (_)-month period, the
Purchaser shall acquire a vested interest in, and the Repurchase Right shall
lapse with respect to, that number of Purchased Shares equal to
_________________ percent (_%) of the Total Purchasable Shares under the Option
(without adjustment for shares already Purchased pursuant to such Option).

     (iii) The Purchaser shall acquire a vested interest in, and the Repurchase
Right shall lapse with respect to, the remaining Purchased Shares in a series of
____________ (__)consecutive monthly installments, each equal to _____________
(__) of the Purchased Shares, with the first such installment to vest at the end
of the _____________ (__) calendar month period measured from the Grant Date.

     3.4 Fractional Shares. No fractional shares shall be repurchased by the
Corporation. Accordingly, should the Repurchase Right extend to a fractional
share (in accordance with the vesting computation provisions of Section 3.3) at
the time the Purchaser ceases to be an Employee of the Corporation, then such
fractional share shall be added to any fractional share in which the Purchaser
is then vested in order to make one whole vested share no longer subject to the
Repurchase Right.

     3.5 Additional Shares or Substituted Securities. Should any change be made
to the Corporation's outstanding Common Stock by reason of any stock dividend,
stock split, combination of shares, recapitalization or other transaction
affecting the Corporation's outstanding Common Stock as a class without receipt
of consideration, then any new, substituted or additional securities or other
property (including money paid other than as a regular cash dividend) which is
by reason of any such transaction distributed with respect to the Purchased

<PAGE>
                                      -5-


Shares shall be immediately subject to the Repurchase Right, but only to the
extent the Purchased Shares are at the time covered by such right, and
appropriate adjustments to reflect the distribution of such securities or
property shall be made to the number of Purchased Shares for all purposes
relating to the Repurchase Right, and the Corporation (or its successor) may
require the establishment of an escrow account for any money (other than cash
dividends) distributed with respect to the Purchased Shares covered by the
Repurchase Right in order to facilitate the exercise of such right. Appropriate
adjustments shall also be made to the price per share to be paid upon the
exercise of the Repurchase Right in order to reflect the effect of any such
transaction upon the Corporation's capital structure; provided, however, that
the aggregate purchase price shall remain the same.

     3.6 Permanent Right of First Refusal. Any shares in which the Purchaser
acquires a vested interest under this Article III may not be transferred,
assigned, encumbered or otherwise made the subject of disposition in
contravention of the Corporation's First Refusal Right under Article IV.


IV.      PERMANENT RIGHT OF FIRST REFUSAL


     4.1 Grant. The Corporation is hereby granted a permanent right of first
refusal ("First Refusal Right") with respect to each and every proposed
disposition of the Purchased Shares by the Purchaser, other than a permitted
transfer under Section 2.1. The First Refusal Right shall be a permanent
restriction on the Purchased Shares and shall accordingly bind the Purchaser,
any other Owner of the Purchased Shares and each and every other holder of
record of the Purchased Shares, all of whom shall be collectively referred to in
this Article IV as the "Holder."

     4.2 Notice of Intended Disposition. In the event the Holder desires to sell
or otherwise transfer for value any or all of the Purchased Shares which are
vested pursuant to the provisions of Section 3.3 (the vested shares which are
the subject of such offer to be hereinafter called, solely for purposes of this
Article IV, the "Target Shares"), the Holder shall promptly deliver to the
Secretary of the Corporation written notice of such intention, including the
number of Purchased Shares the Holder wishes to sell and a summary of the terms
and conditions of any bona fide third-party offer received for the shares (the
"Disposition Notice").


<PAGE>
                                      -6-


     4.3 Exercise of Right. The Corporation (or its assigns) shall, for a period
of sixty (60) days following receipt of the Disposition Notice under paragraph
4.2, have the right to repurchase all of the Target Shares specified in the
Disposition Notice at a price per share determined in accordance with the
Section 4.4 formula. Such right shall be exercisable by written notice delivered
to the Holder prior to the expiration of the sixty (60) day exercise period. If
such right is exercised, the Corporation (or its assigns) shall effect the
repurchase of the Target Shares, including payment of the formula price, not
more than sixty (60) days thereafter; and at such time the Holder shall deliver
to the Corporation the certificates representing the Target Shares to be
repurchased, each certificate to be properly endorsed for transfer.

     4.4 Formula Price. The price per share at which the Corporation may
exercise its First Refusal Right under Section 4.3 shall be determined in
accordance with the following formula:

     X = M - $ __ , where

     X = the price per share at which the Corporation may repurchase the Target
Shares, and

     M = the fair market value per share of the Target Shares (determined under
Section 4.7 without regard to the Corporation's permanent First Refusal Right)
on the date immediately preceding the date such right is exercised.

     4.5 Non-Exercise of Right. In the event the Exercise Notice is not given to
the Holder within sixty (60) days following the date of the Corporation's
receipt of the Disposition Notice, the Holder shall have a period of fifteen
(15) days thereafter in which to sell or otherwise dispose of the Target Shares
(I) at a price not less than that, and on terms no more favorable than those,
set forth in the Disposition Notice or, if no terms are set forth in the
Disposition Notice, (II) for a current cash payment equal to the fair market
value (adjusted to reflect the First Refusal Right) of the Target Shares. The
third-party purchaser and all subsequent purchasers of the Target Shares shall
acquire the Target Shares subject to the First Refusal Right under this Article
IV. In the event the Holder does not effect an authorized sale or other
disposition of the Target Shares within the specified fifteen (15) day period,
the Holder must once again provide the requisite Section 4.2 notice prior to any
subsequent disposition of the Purchased Shares.


<PAGE>
                                      -7-


     4.6 Recapitalization. In the event of any stock dividends stock split,
recapitalization or other transaction affecting the Corporation's outstanding
securities without receipt of consideration, then any new, substituted or
additional securities or other property (including money paid other than as a
cash dividend) which is by reason of such transaction distributed with respect
to the Purchased Shares shall be immediately subject to the Corporation's First
Refusal Rights under this Article IV, but only to the extent the Shares are at
the time covered by such right.

     4.7 Valuation. For purposes of determining the Section 4.4 formula price,
the fair market value per share of the Target Shares or the relevant valuation
date shall be determined as follows:

     (i) If the Corporation's common stock is not at the time listed or admitted
to trading on any stock exchange, but is traded in the over-the-counter market,
the fair market value shall be the closing selling price of one share of such
common stock on the valuation date in the over-the-counter market, as such price
is quoted on the NASDAQ National Market System. If there are no reported closing
selling price for the valuation date, then the closing selling price on the last
date preceding the valuation date for which such price is granted shall be
determinative of fair market value.

     (ii) If the Corporation's common stock is at the time listed or admitted to
trading on any stock exchange, the fair market value shall be the closing
selling price of one share of common stock on the valuation date on the stock
exchange determined by the Plan Administrator to be the primary market for the
common stock, as such price is officially quoted on such exchange. If there is
no reported sale of common stock on such exchange on the valuation date, then
the fair market value shall be the closing selling price on the exchange on the
last date preceding the valuation date for which such quotation exists.

     4.8 Nonlapse. The First Refusal Right under this Article IV is intended to
be a "restriction which by its terms will never lapse" within the meaning of
Section 83(d) of the Internal Revenue Code and shall accordingly be binding upon
each and every Holder of the Purchased Shares.

     4.9 Transferee Obligations. Each person to whom the Target Shares are
transferred by means of a transfer effected in accordance with this Article IV
must as a condition prece-


<PAGE>
                                      -8-


dent to the validity of such transfer acknowledge in writing to the Corporation
that such person is bound by the provisions of this Agreement and that the
transferred shares shall remain subject to the Corporation's First Refusal Right
hereunder.


V.   GENERAL PROVISIONS APPLICABLE TO REPURCHASE RIGHT AND FIRST REFUSAL RIGHT.


     5.1 Assignment. The Corporation may assign its Repurchase Right under
Article III and/or its First Refusal Right under Article IV to any person or
entity selected by the Corporation's Board of Directors, including (without
limitation) one or more shareholders of the Corporation.

     If the assignee of the Repurchase Right is other than a subsidiary
corporation of the Corporation, then such assignee must make a cash payment to
the Corporation, upon the assignment of the Repurchase Right, in an amount equal
to the excess (if any) of the fair market value of the Unvested Shares at the
time subject to the Repurchase Right and the aggregate repurchase price payable
for such Unvested Shares.

     5.2 Notices. Any notice required in connection with the exercise of the
Corporation's Repurchase Right or First Refusal Right shall be given in writing
and shall be deemed effective upon personal delivery or upon deposit in the
United States mail, registered or certified, postage prepaid and addressed to
the party entitled to such notice at the address indicated below such party's
signature line on this Agreement or at such other address as such party may
designate by 10 days advance written notice under this Section 5.2 to all other
parties to this Agreement.

     5.3 No Waiver. The failure of the Corporation (or its assigns) in any
instance to exercise the Repurchase Right granted under Article III or the First
Refusal Right under Article IV shall not constitute a waiver of any other
repurchase rights or rights of first refusal that may subsequently arise under
the provisions of this Agreement or any other agreement with the Corporation. No
waiver of any breach or condition of this Agreement shall be deemed to be a
waiver of any other or subsequent breach or condition, whether of like or
different nature.

     5.4 Definitions. For purposes of this Agreement, each corporation (other
than the Corporation) in an unbroken 


<PAGE>
                                      -9-


chain of corporations beginning with the Corporation shall be considered to be a
subsidiary of the Corporation, provided each such corporation (other than the
last corporation) in the unbroken chain owns, at the time of the determination,
stock possessing fifty percent (50%) or more of the total combined voting power
of all classes of stock in one of the other corporations in such chain.

     5.5 Cancellation of Shares. If the Corporation (or its assigns) shall make
available, at the time and place and in the amount and form provided in this
Agreement, the consideration for the Purchased Shares to be repurchased in
accordance with the provisions of this Agreement, then from and after such time,
the person from whom such shares are to be repurchased shall no longer have any
rights as a holder of such shares (other than the right to receive payment of
such consideration in accordance with this Agreement) and such shares shall be
deemed purchased in accordance with the applicable provisions hereof and the
Corporation (or its assigns) shall be deemed the owner and holder of such
shares, whether or not the certificates therefor have been delivered as required
by this Agreement.

     5.6 Legend. All certificates representing the Purchased Shares shall be
endorsed with the following legend:

          "THIS CERTIFICATE AND THE SHARES REPRESENTED HEREBY MAY NOT BE SOLD,
          ASSIGNED, TRANSFERRED, ENCUMBERED, OR IN ANY MANNER DISPOSED OF EXCEPT
          IN CONFORMITY WITH THE TERMS OF A WRITTEN AGREEMENT, DATED
          ____________, 19 _ , BETWEEN THE COMPANY AND THE REGISTERED HOLDER OF
          THE SHARES (OR THE PREDECESSOR IN INTEREST TO THE SHARES). SUCH
          AGREEMENT GRANTS THE CORPORATION (AND ITS ASSIGNS) CERTAIN REPURCHASE
          RIGHTS AND RIGHTS OF FIRST REFUSAL TO REPURCHASE THE SHARES UPON ANY
          PROPOSED SALE, ASSIGNMENT, TRANSFER, ENCUMBRANCE OR OTHER DISPOSITION
          OF THE SHARES OR UPON TERMINATION OF SERVICE WITH THE CORPORATION. THE
          FIRST REFUSAL RIGHTS ARE PERMANENT AND WILL BE BINDING UPON EACH AND
          EVERY HOLDER OF THE SHARES. THE CORPORATION WILL UPON WRITTEN REQUEST
          FURNISH A COPY OF SUCH AGREEMENT TO THE HOLDER HEREOF WITHOUT CHARGE."



<PAGE>
                                      -10-


VI.      MISCELLANEOUS PROVISIONS


     6.1 Purchaser Undertaking. Purchaser hereby agrees to take whatever
additional action and execute whatever additional documents the Corporation may
in its judgment deem necessary or advisable in order to carry out or effect one
or more of the obligations or restrictions imposed on either the Purchaser or
the Purchased Shares pursuant to the express provisions of this Agreement.

     6.2 Agreement is Entire Contract. This Agreement constitutes the entire
contract between the parties hereto with regard to the subject matter hereof.
This Agreement is made pursuant to the provisions of the Plan and shall in all
respects be construed in conformity with the express terms and provisions of the
Plan.

     6.3 No Employment Contract. Nothing in this Agreement or in the Plan shall
confer upon the Purchaser any right to continue in the employ of the Corporation
(or any subsidiary corporation of the Corporation employing Purchaser) for any
period of specific duration or interfere with or otherwise restrict in any way
the rights of the Corporation (or any subsidiary corporation of the Corporation
employing Purchaser) or the Purchaser, which rights are hereby expressly
reserved by each, to terminate the Employee status of Purchaser at any time for
any reason whatsoever, with or without cause.

     6.4 Governing Law. This Agreement shall be governed by, and construed in
accordance with, the laws of the State of California, as such laws are applied
to contracts entered into and performed in such State.

     6.5 Counterparts. This Agreement may be executed in counterparts, each of
which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument.

     6.6 Successors and Assigns. The provisions of this Agreement shall inure to
the benefit of, and be binding upon, the Corporation and its successors and
assigns and the Purchaser and the Purchaser's legal representatives, heirs,
legatees, distributees, assigns and transferees by operation of law, whether or
not any such person shall have become a party to this Agreement and have agreed
in writing to join herein and be bound by the terms and conditions hereof.


<PAGE>
                                      -11-


     6.7 Power of Attorney. Purchaser's spouse hereby appoints Purchaser his or
her true and lawful attorney in fact, for him or her and in his or her name,
place and stead, and for his or her use and benefit, to agree to any amendment
or modification of this Agreement and to execute such further instruments and
take such further actions as may reasonably be necessary to carry out the intent
of this Agreement. Purchaser's spouse further gives and grants unto Purchaser as
his or her attorney in fact full power and authority to do and perform every act
necessary and proper to be done in the exercise of any of the foregoing powers
as fully as he or she might or could do if personally present, with full power
of substitution and revocation, hereby ratifying and confirming all the
Purchaser shall lawfully do and cause to be done by virtue of this power of
attorney.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
and year first written above.

                                    XOMA CORPORATION


                                    By
                           Address:___________________________________
                                   ___________________________________
                                   ___________________________________

                                   ___________________________________
                                                          , Purchaser
                           Address:___________________________________
                                   ___________________________________
                                   ___________________________________

                                   ___________________________________
                                                   , Purchaser Spouse



                     INTERNATIONAL GENETIC ENGINEERING, INC.
                       1985 NONQUALIFIED STOCK OPTION PLAN

     1. ESTABLISHMENT, PURPOSE, AND DEFINITIONS.

     (a) There is hereby established the 1985 Nonqualified Stock Option Plan
(the "Plan") of International Genetic Engineering, Inc. (the "Company"). The
Plan permits the granting to "significant employees or consultants," (as
hereinafter defined) of stock options ("Options"). These Options are not
intended to qualify as incentive stock options under Section 422A of the
Internal Revenue Code of 1954, as amended (the "Code").

     (b) The purpose of this Plan is to provide a means by which significant
employees and consultants of the Company or its affiliates may be given an
opportunity to purchase shares of the Common Stock of the Company (the "Stock")
pursuant to Options.

     (c) In the absence of contrary action by the Board of Directors of the
Company (the "Board"), any action taken by the Board, or by the committee of
directors appointed by the Board to administer the Plan (such committee being
hereinafter referred to as the "Committee") with respect to the implementation,
interpretation or administration of the Plan shall be final, conclusive and
binding. The Committee shall have authority to grant options, to establish the
terms and conditions thereof and otherwise to act for the Company with respect
to the Plan, except as provided in Paragraph 9.

     (d) The term "affiliates" as used in the Plan means parent or subsidiary
corporations of the Company, as defined in section 425 of the Code (but
substituting "Company" for "employer corporation"), including parents or
subsidiaries which become such after adoption of the Plan. The term "significant
employees and consultants" shall mean one or more employees, officers,
consultants or directors of the Company or its affiliates who, in the judgment
of the Committee or the Board (as hereinafter defined), render those types of
services which tend to contribute materially to the success of the Company or
which may reasonably be anticipated to contribute materially to the future
success of the company.

     2. STOCK SUBJECT TO THE PLAN.

     (a) Options may be granted under this Plan from time to time to significant
employees and consultants to purchase an aggregate of no more than 550,000
shares of Stock. As the Committee or the Board may determine from time to time,
the shares may consist either in whole or in part of shares of authorized but
unissued Stock, or shares of authorized and issued Stock reacquired by the
Company and held in its treasury. If an Option ceases to be exercisable in whole
or in part, the shares which were subject to such Option, but as to which the

                                       -2-

<PAGE>


Option had not been exercised, shall continue to be available for granting under
the Plan.

     (b) It there shall be any change in the Stock subject to this Plan or the
Stock subject to any Option granted hereunder, through merger, consolidation,
reorganization, recapitalization, reincorporation, stock split, stock dividend,
or other change in the corporate or capital structure of the Company (including
a liquidating dividend but not an ordinary and reasonable dividend), that event
shall simultaneously, and without any further action by the Committee or the
Board, cause appropriate adjustments to be made in (i) the number of shares and
the price per share subject to outstanding Options in order to preserve, but not
to increase, the benefits of the optionee, so that immediately after such event
each holder of an Option shall be entitled, upon payment to the Company of the
aggregate amount of money provided in the Option, to receive that number of
shares or other property that he would have received it he had exercised the
Option in full (without regard to any provisions relating to the dates on which
the Option becomes exercisable) immediately prior to such event; and (ii) the
aggregate number of shares subject to this Plan. Provided, however, that subject
to any required action by the stockholders of the Company, if there shall be a
dissolution or liquidation of the Company or if the Company shall not be the
surviving corporation in any merger, consolidation or reorganization or

                                       -3-

<PAGE>


if eighty percent (80%) or more of the Company's then outstanding voting stock
is acquired by another corporation or if the Company agrees to sell
substantially a11 of its assets and property to another person (a "Terminating
Event"), each optionee shall have the right immediately prior to such
dissolution, liquidation, merger, consolidation, reorganization, acquisition or
sale of assets to exercise his Option(s) to the extent not theretofore
exercised, whether or not they are then exercisable in the ordinary course of
events, unless there is a surviving corporation or a parent or subsidiary
corporation thereof that shall assume (with appropriate changes) the outstanding
Options or replace them with new options of comparable value. The Company shall
give reasonable notice of any Terminating Event. Thirty (30) days after delivery
of such notice, every Option or any portion thereof outstanding hereunder shall
thereupon terminate, unless there is a surviving corporation or a parent or
subsidiary corporation thereof that shall assume (with appropriate changes) the
outstanding Options or replace them with new options of comparable value.

     3. ELIGIBILITY.

         The significant employees and consultants who shall be eligible to have
Options granted to them are defined to be those employees and consultants as the
Committee or the Board, in its absolute discretion, shall designate from time to
time.

                                       -4-

<PAGE>


     4. ADMINISTRATION OF THE PLAN.

     (a) The Plan shall be administered by the Committee. The Board may from
time to time remove members from, or add members to, the Committee. Vacancies on
the Committee, however caused, shall be filled by the Board. The Committee shall
hold meetings at such times and places as it may determine. A majority of the
Committee shall constitute a quorum. A majority of the members present may act
at any meeting at which a quorum is present. Any action that may be taken at a
meeting may be taken without a meeting if reduced to and approved in writing by
all the members of the Committee. Options may be granted to significant
employees who are members of the Committee, provided that they are approved by a
majority of the members of the whole Committee with the person to whom Options
are to be issued not voting, unless the Company's shares become subject to the
Securities and Exchange Act of 1934. If the Company becomes subject to the
Securities and Exchange of 1934, no options may be granted to any member of the
Committee during the term of his or her membership on the Committee. No person
shall be eligible to serve on the Committee unless he or she is then a
"disinterested person" within the meaning of paragraph (b) of Rule 16B-3, which
has been adopted by the Securities and Exchange Commission under the Securities
Exchange Act of 1934, if and as such rule is then in effect.

                                       -5-

<PAGE>


     (b) Subject to and consistent with the provisions of this Plan, either the
Board or the Committee may from time to time determine which significant
employees and consultants shall be granted Options, the terms and conditions
thereof, and the number of shares for which an Option or Options shall be
granted to an optionee.

     (c) In addition to any other authority it may have, either the Board or the
Committee shall have authority, subject to and consistent with the provisions of
this Plan:

          (1) To substitute Options with different terms for previously granted
     Options;

          (2) To amend the terms of any Option or Options previously granted,
     including the authority to reduce the Option exercise price from time to
     time, but not to reduce the price below the price as determined under
     Paragraph 5; and

          (3) To accept, upon exercise of Options, consideration other than
     cash, including without limitation, a promissory note or notes of the
     Optionee, shares of the Company's Stock valued at its fair market value at
     the time or the surrender of options to purchase Stock, valued at the
     difference between fair market value at the time of the Stock subject to
     the Option less the exercise price thereof.

                                       -6-

<PAGE>


     If the Stock is neither listed nor admitted to trading on any stock
exchange nor actively traded in the over-the-counter market at the time an
Option is granted, then the Committee or the Board shall in good faith determine
the fair market value of the Stock on the basis of such criteria as may appear
to it to be reasonable at the time. If the Stock is listed or admitted to
trading on a stock exchange or is actively traded over-the-counter at the time
the Option is granted, the fair market value shall be the mean between the
highest reported bid price and the lowest reported asked price of the Stock in
the over-the-counter market on the last business day prior to the date the
Option is granted, as reported by any publication selected by the Company which
regularly reports the market price of the Stock in such market. If the Stock is
then listed or admitted to trading on any stock exchange, the fair market value
shall be the last reported sales price on the last business day prior to the
date the Option is granted on the principal stock exchange on which the Stock is
then listed or admitted to trading as reported by any publication selected by
the Company which regularly reports the market price of the Stock on such
exchange, or, if no sale takes place on such day on such principal stock
exchange, then the closing bid price of the Stock on such exchange on such day.
Such price shall be subject to adjustment as provided in Paragraph 2(b) hereof.

                                       -7-

<PAGE>


     (d) The Board or the Committee shall report to the Secretary of the Company
the names of persons to whom Options have been granted, the number of shares
covered by each Option, and the terms and conditions of each such Option.

     (e) Subject to the terms and conditions of the Plan, either the Board or
the Committee shall have full power to adopt, amend, and rescind roles and
regulations relating to its administration of this Plan; to construe and
interpret this Plan, such rules and regulations, and the instruments evidencing
Options; and to make all other determinations deemed necessary or advisable for
the administration of this Plan. All decisions, determinations, and
interpretations of the Board of Directors and the Committee shall be final and
binding.

     5. THE OPTION EXERCISE PRICE.

     (a) the exercise price of the Stock covered by each Option shall be not
less than 100 percent of the fair market value of such stock, as determined in
good faith by the Committee or the Board (as the case may be), on the date the
Option is granted. For all purposes hereof, the date on which an Option is
granted shall be the date on which the Committee or the Board determines to make
the grant and establishes the price thereof, without regard to subsequent delays
in approvals of other terms and conditions or preparation of documents.

                                       -8-

<PAGE>


     (b) The Option price shall be paid in full at the time of exercise of the
Option in cash, by check, or, at the discretion of the Committee or the Board,
by delivering stock of the Company already owned by the Optionee, or also at the
discretion of the Committee or the Board, by the promissory note or notes of the
Optionee, or at the discretion of the Committee or the Board by a combination of
these methods. The value of any stock delivered in payment shall, prior to the
stock's being publicly traded, be the fair market value of the stock as
determined by the Committee or the Board and, after the stock is publicly
traded, be the fair market value of the Company's stock, as defined in Section
4(c) but using market quotations on the last business day prior to delivery. Any
promissory notes shall bear a rate of interest not less than the rate, as it may
change from time to time, required under federal tax law to prevent any
imputation of interest, unless the rate exceeds the maximum rate permissible
under California law, in which case the rate shall be the maximum permitted
under California law. Such promissory notes shall be secured by a security
interest in the shares issued upon exercise and such other security, if any as
the Committee or the Board may require. All other terms of such loan shall be
determined solely by the Committee, and all terms and conditions, including
whether the loan shall become due upon cessation of employment, shall be set
forth in the promissory note or notes executed by the Optionee. The Committee
shall

                                       -9-

<PAGE>

furnish the Optionee with a Truth-in-Lending Statement showing the terms of the
loan, including the amount financed, total payments of interests, total payments
of principal and annual percentage rate. The Board or Committee may in its
discretion, during any time in which any portion of the loan is outstanding,
provide for forgiveness of the loan, on such terms and conditions as the Board
or Committee shall determine.

     6. TERMS AND CONDITIONS OF OPTIONS.

     (a) Each Option granted pursuant to this Plan shall be evidenced by a
written Stock Option Agreement executed by the Company and the person to whom
such Option is granted, in such form and on such terms as the Board or the
Committee shall approve from time to time, but subject to the following
subparagraphs (b) and (c) of this Paragraph 6.

     (b) Each Stock Option Agreement entered into pursuant to this Plan shall
contain at least the following provisions:

          (1) The number of shares that may be purchased upon exercise of the
     Option and such exercise price as the Board of Directors or the Committee
     may determine, but which is not less than the price determined in
     accordance with Paragraph 5;

                                      -10-

<PAGE>


          (2) A prohibition against the transfer of any Option to purchase Stock
     other than a transfer by will or the laws of descent and distribution and a
     limitation that the Option is exercisable during the optionee's lifetime
     only by him or after his death by his legal representative;

          (3) Provisions for termination of the Option thirty days after
     termination of employment except for cause or for death or permanent and
     total disability of the Option holder, one year in the event of termination
     of employment by reason of death or permanent and total disability, and
     immediate termination of the Option in the event of termination for cause;
     and

          (4) Such term for any Option, which is not in excess of a period of
     ten years and one day from the date it is granted as the Committee or the
     Board may determine and a schedule under which at least 20% of the shares
     granted under this Option shall become exercisable each year.

                                      -11-

<PAGE>


     (c) Each Stock Option Agreement may also contain:

               (1) Such provisions as are necessary to render the issuance of
          Stock in compliance with all applicable requirements of law and to
          relieve the Company of any obligation to issue or deliver Stock unless
          and until, in the opinion of the Company's counsel, there has been
          full compliance with all applicable requirements of the securities
          laws and all applicable listing requirements of any national
          securities exchange on which shares of the same class are then listed;

               (2) Such restrictions on sale or other disposition of the Stock
          purchased upon exercise of the Option as may be determined by the
          Board or the Committee; and

               (3) Such other terms and conditions not inconsistent with this
          Plan as may be determined by the Board or the Committee.

     7. USE OF PROCEEDS.

     Proceeds realized from the sale of Stock pursuant to Options granted under
this Plan shall constitute general funds of the Company.

                                      -12-

<PAGE>


     8. AMENDMENT, SUSPENSION, OR TERMINATION OF PLAN.

     The Board may at any time suspend or terminate this Plan, and may amend it
from time to time in such respects as the Board may deem advisable; provided,
however (except as provided in Paragraph 2(b) hereof), the Board shall not amend
the Plan in the following respects without shareholder approval:

     (a) To increase the maximum number of shares subject to the Plan; or

     (b) To change the designation of class of persons eligible to receive
Options under the Plan.

     No amendment, suspension, or termination of this Plan shall, without the
optionee's consent, alter or impair any rights or obligations under any Option
theretofore granted to him under this Plan.

     9. EFFECTIVE DATE AND TERMINATION OF PLAN.

     (a) The Plan was adopted by the Board and became effective on December 19,
1985. The Plan was approved by the shareholders of the Company on November 20,
1985.

     (b) Unless sooner terminated by the Board, the Plan shall terminate ten
years and one day after the date of Board approval as stated in Paragraph 9(a).

                                      -13-

<PAGE>


                     INTERNATIONAL GENETIC ENGINEERING, INC.
                      STOCK OPTION AGREEMENT UNDER THE 1985
                         NONQUALIFIED STOCK OPTION PLAN

     THIS AGREEMENT is dated as of the (blank) day of (blank), 19 (blank) by and
between International Genetic Engineering, Inc. (the "Company") and (blank)
("Optionee").

     WHEREAS, pursuant to the 1985 Nonqualified Stock Option Plan of the Company
(the "Plan"), the Board of Directors (the "Board") of the Company or the Stock
Incentive Committee (the "Committee") of the Board has authorized granting to
Optionee a Non-Qualified Stock Option (the "Option") to purchase shares of
common stock of the Company in accordance with and on the terms and conditions
hereinafter stated;

     NOW, THEREFORE, it is hereby agreed:

     1. Grant of Option. Subject to the terms and conditions of the Plan, which
is incorporation herein by reference and a copy of which is available to
Optionee upon request, and pursuant to the action of the Board of the Committee
and in accordance with authorizations granted by all appropriate regulatory and
governmental agencies, the Company hereby grants to Optionee the Option to
purchase all or any part of (blank) shares of common stock of the Company at the
price of $(blank) per share, which price has been determined by the Board or the
Committee. The date of grant of this Option is the date first above set forth.
<PAGE>

     2. Exercise.

     (a) This Option shall be exercisable as follows:

     (blank)

     (b) This Option shall remain exercisable as to all of such shares until ten
years and one day from the date of grant of this Option, unless this Option has
expired or terminated earlier in accordance with the provisions hereof. Shares
as to which this Option becomes exercisable pursuant to the foregoing provision
may be purchased at any time prior to expiration of this Option.

     (c) Notwithstanding the preceding provisions of this paragraph, upon
delivery of notice from the Company of the pendency of dissolution or
liquidation of the Company or a reorganization, merger, consolidation of the
Company with one or more corporations as a result of which the Company will not
be the surviving corporation, or the acquisition of eighty percent (80%) or more
of the Company's then outstanding voting stock by another corporation, a sale of
substantially all of the assets and property of the Company to another person (a
"Terminating Even"), this Option shall be exercisable in full and not merely as
to those shares with respect to which installments, if any, have then accrued,
unless there is a

                                       -2-
<PAGE>
surviving corporation or a parent or subsidiary corporation thereof that shall
assume (with appropriate changes) the outstanding Options or replace them with
new options of comparable value. Notwithstanding the above, if this Option shall
expire within 30 days of delivery of said notice pursuant to Section 3(b), 4, 5
or 6 of this Agreement, this Section 2(c) shall have no effect. Thirty (30) days
after delivery or said notice, this Option or any portion hereof not exercised
shall terminate, unless provision be made in connection with the Terminating
Event for assumption of this Option or for substitution of new options for this
Option covering an equivalent amount of stock of a successor employer
corporation, or a parent or subsidiary corporation thereof, solely at the
election of such successor corporation or parent or subsidiary corporation, with
appropriate adjustments as to number and kind of shares and prices.

     (d) This Option shall be subject to appropriate adjustment sin price and
number of shares to reflect any stock split, stock dividend, recapitalization or
similar event (other than those specified in (c) above), as set forth in Section
2(b) of the Plan.

     3. Exercise of Option. This Option may be exercised only in 100-share lots,
or, if less than 100 shares remain to be purchased upon exercise of any vested
installments of this Option, then to the extent of the remaining shares which
may be

                                       -3-
<PAGE>
purchased. The Option shall be exercised by delivery to the Company of (a)
written notice of exercise stating the number of shares being purchased; (b)
cash, check, or, at the discretion of the Committee or the Board, delivery of
stock of the Company already owned by the Optionee, or also at the discretion of
the Committee or the Board, by execution and delivery of the promissory note or
notes of the Optionee, or at the discretion of the Committee or the Board by a
combination of these methods; and (c) the written statement provided for in
Section 8(b) hereof.

     4. Cessation of Employment (Other Than Death or Total Disability). Except
as provided in Paragraph 5 hereof, if Optionee shall cease to be employed by the
Company or a subsidiary corporation for any reason other than Optionee's
permanent and total disability or death, this Option shall expire thirty (30)
days after the date on which the Optionee ceases employment or on the date
specified in Paragraph 2 hereof, whichever is earlier. Before such expiration,
Optionee shall have the right to exercise this Option only as to those shares
with respect to which installments, if any, had accrued under Paragraph 2 hereof
at the date of termination of employment.

     5. Termination of Employment for Cause. If Optionee's employment by the
Company or a patent or subsidiary corporation is terminated for cause, this
Option shall expire immediately. Termination for cause shall include termination
for malfeasance or gross misfeasance in the performance of duties or conviction
of a felony or any conduct intentionally detrimental to the interests of the
Company or a parent or subsidiary corporation, or any other cause as specified
in any employment agreement between the Company and the Optionee, and in any
event, determination of the Board with respect thereto shall be final and
conclusive.

     6. Nontransferability; Death or Total Disability of Optionee. This Option
shall not be transferable except by will or by the laws of descent and
distribution and shall be exercisable during Optionee's lifetime only by
Optionee. If Optionee dies, or is permanently and totally disabled, while
employed by the Company or a subsidiary corporation, this Option shall expire
one(1) year after the date of Optionee's death, or permanent and total
disability, or on the day specified in paragraph 2 hereof, whichever is earlier.
After Optionee's death but before such expiration, the persons to whom
Optionee's rights under this Option shall have passed by will or by the
applicable laws of descent and distribution, or a person lawfully entitled to
act for him, shall have the right to exercise this Option only as to those
shares, if any, for which installments had accrued under Paragraph 2 hereof as
of the date on which Optionee ceased to be employed by the Company or subsidiary
corporation. Shares purchased by such persons shall be subject to all of the
terms and provisions of this Agreement.

                                       -4-
<PAGE>
     7. Employment. This agreement shall not obligate the Company or a
subsidiary corporation to employ Optionee for any period, nor shall it interfere
in any way with the right of the Company or a subsidiary corporation to reduce
Optionee's compensation or to terminate the employment of Optionee.

     8. Privileges and Restrictions of Stock Ownership.

     (a) Optionee shall have no rights as a stockholder with respect to common
stock of the Company subject to this Option until the date of issuance of stock
certificates to him. Except as provided in Section 3(b) of the Plan, no
adjustment will be made for dividends or other rights for which the record date
is prior to the date such stock certificates are issued.

     (b) By accepting this Option, Optionee, for himself and his transferees by
will or the laws of descent and distribution, agrees that any and all shares
purchased upon exercise of this Option shall be acquired for investment and not
for sale or for distribution, that each notice of the exercise of any portion of
this Option shall be accompanied by a representation and agreement in writing,
signed by the person entitled to exercise the same, that the shares are being
acquired in good faith for investment and not for sale or for distribution and
that any and all certificates presenting shares purchased on the exercise of
this Option may have affixed thereto an appropriate legend indicating that such
shares have not been

                                       -5-
<PAGE>
registered under the Securities Act of 1933, as amended, and are subject to
certain restrictions on transfer, and shall be subject to such restrictions on
transfer, and related legends, as in the opinion of counsel may be reasonably
prudent under the circumstances. Provided, however, that if the shares subject
to this Option are registered under the Securities Act of 1933, as amended, and
if other applicable laws do not require similar restrictions at the time, the
requirements set forth in this Section 8 shall be of no force and effect, and
the Optionee may acquire such shares without giving such a representation.

     9. Modification and Termination. The rights of Optionee are subject to
adjustment, modification and termination as provided in Paragraph 2 (relating to
adjustments to reflect reorganizations, recapitalizations and like
transactions), 4 (relating to authority in administration of the Plan) and 9
(relating to amendment, termination and suspension of the Plan) of the Plan.

     10. Notification of Sale. Optionee agrees that Optionee, or any person
acquiring shares upon exercise of this Option, will notify the Company not more
than five (5) days after any sale or disposition of such shares.

                                       -6-
<PAGE>
     11. Withholding Taxes. Whenever shares are to be issued in satisfaction of
this Option, the Company shall have the right to require Optionee to remit to
the Company an amount sufficient to satisfy any federal, state and local
withholding tax requirements prior to the delivery of any certificate or
certificate of such shares.

     12. Notices. Notices delivered under this Agreement shall be delivered to
the Company, at its principal office (Attention: President), and to the Optionee
at such address as Optionee shall designate to the Company.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement.

OPTIONEE:                       INTERNATIONAL GENETIC
                                ENGINEERING, INC.

                                By (blank)

                                       -7-




                              ASSUMPTION AGREEMENT
                     INTERNATIONAL GENETIC ENGINEERING, INC.
                       1985 NONQUALIFIED STOCK OPTION PLAN

     This Agreement is made as of November 13, 1989, by an between XOMA
Corporation, a Delaware Corporation ("XOMA") and (blank) ("Employee").

     WHEREAS:

     1. International Genetic Engineering, Inc. ("INGENE"), XOMA, and XOMA
Acquisition Corporation, a wholly owned subsidiary of XOMA ("Sub"), entered into
the First Amended and Restated Agreement and Plan of Reorganization dated as of
August 10, 1989 and an Agreement of Merger dated as of November 13, 1989.

     2. Effective November 13, 1989 ("Merger Effective Date"), pursuant to the
Agreement of Merger, Sub was merged with and into INGENE.

     3. Employee is the holder of an outstanding option granted prior to the
Merger Effective Date, to purchase shares of INGENE Common Stock under the
International Genetic Engineering, Inc. 1985 Nonqualified Stock Option Plan
("Plan").

     4. Employee's outstanding option is evidenced by an option agreement
("Original Option Agreement") specifying the terms and conditions upon which the
outstanding option may be exercised.

     5. Pursuant to Section 4.03(a) of the Agreement of Merger and Section 2(b)
of the Plan, XOMA has agreed to assume the obligations of INGENE under all
options outstanding under the Plan on the Merger Effective Date.

     NOW THEREFORE, effective as of the Merger Effective Date, the parties agree
as follows:

     A. Employee warrants and represents that Employee is the holder of an
option to purchase the number of shares of INGENE Common Stock indicated in the
table below ("TABLE"), at the specified exercise price per share ("INGENE
Option").

     B. The terms and conditions of the INGENE Option are amended as follows:

     (1) The shares purchasable under the Original Option Agreement shall be
shares of XOMA Common Stock.

     (2) All references to the Company in the Plan and the Original Option
Agreement shall be references to XOMA.

     (3) The number of XOMA shares purchasable under the INGENE Option assumed
by XOMA, and the exercise price of those shares are adjusted as indicated in the
TABLE to reflect the exchange ratio at which shares of INGENE Common Stock were
converted into shares of XOMA Common Stock under the Agreement of Merger.

<TABLE>
                                      TABLE
<CAPTION>
                  INGENE OPTION                                        XOMA OPTION
                                                                                                 Adjusted
                  Number of                 Exercise                   Number of                 Exercise
Date              Unexercised               Price                      Shares of                 Price
Granted           INGENE Shares             Per Share                  XOMA                      Per Share
<S>               <C>                       <C>                        <C>                       <C>
(blank)
</TABLE>

     C. With the exception of the above amendments, the terms and conditions of
the INGENE Options, as set forth in the Plan and the Original Option Agreement,
remain in full force and effect.

     D. With respect to the INGENE Option, XOMA assumes all obligations of
INGENE and agrees to issue up to the number of shares of XOMA Common Stock
indicated in the TABLE upon exercise of the INGENE Option in accordance with
provisions of the Plan and the Original Option Agreement (as amended by this
Agreement) and payment of the adjusted exercise price per share specified in the
TABLE.

     E. This Agreement shall be binding upon, and inure to the benefit of, the
successors and assigns of XOMA and the executors, administrators, heirs and
legatees of the Employee's estate.
<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first set forth above.

(blank)
Employee

XOMA Corporation

By (blank)
Title (blank)




                                AMENDMENT TO THE
                        INTERNATIONAL GENETIC ENGINEERING
                       1985 NONQUALIFIED STOCK OPTION PLAN


     Effective as of October 30, 1996, pursuant to Board action on such date,
the International Genetic Engineering 1985 Nonqualified Stock Option Plan (the
"Ingene Plan") is hereby amended as follows:

     1. Section 4(a) of the Ingene Plan is amended by adding the following at
the end thereof:


         "Notwithstanding anything in the Plan to the contrary, effective
         October 30, 1996, the Plan will be administered by either the full
         Board of Directors (without regard to the number of "non-employee
         directors" (as defined below) on the Board) or, if appointed by the
         Board, a committee thereof comprised of at least two (2) "non-employee
         directors." "Non-employee director" has the meaning set forth in Rule
         16b-3(b)(3) of the Securities and Exchange Commission as amended in
         1996 (or any successor provision thereto). Such director will not be
         required to be a "disinterested person" within the meaning of previous
         Rule 16b-3. However, the mere fact that a Committee member shall fail
         to qualify as a non-employee director shall not invalidate any options
         granted by the Committee which are otherwise validly granted under the
         Plan."




                                XOMA CORPORATION

                        1992 DIRECTORS STOCK OPTION PLAN

               (As Amended and Restated Through October 30, 1996)


     1. General. The XOMA Corporation 1992 Directors Stock Option Plan (the
"Plan") was adopted on February 20, 1992 (the "Adoption Date") by the Board of
Directors of XOMA Corporation (the "Company"), subject to the approval of the
Company's stockholders at its 1992 annual meeting. A total of 150,000 shares of
the Company's Common Stock, par value $.0005 per share ("Common Stock"), have
been reserved for issuance hereunder. The Plan provides for the granting to
non-employee directors of the Company of non-qualified options ("Options" or
"Option") to purchase Common Stock.

     2. Purposes. The purposes of the Plan are to increase the proprietary
interest of non-employee directors in the Company by granting them non-qualified
options to purchase Common Stock, to promote long-term shareholder value through
the potential for increased ownership of Common Stock by non-employee directors,
and to encourage the continued service on the Board of Directors (the "Board")
of non-employee directors.

     3. Administration. The Plan is designed to operate automatically and not
require administration. However, to the extent that administration is necessary,
the Plan shall be administered by those members of the Board who are not
eligible to participate in the Plan (the "Plan Administrators"). Since it is
intended that this Plan provide for grants of Options to non-employee directors
of the Company, this function will be limited to matters of administrative
oversight. Decisions and determinations of the Plan Administrators shall be
final and binding upon all persons having an interest in the Plan. The Plan
Administrators will have no discretion with respect to the selection of
optionees or the determination of the exercise price, the timing of grants or
the number of shares covered by the Options granted hereunder. The Plan
Administrators will receive no additional compensation for their services in
connection with the administration of the Plan.

     4. Eligibility. Each member of the Board who is not a full or part-time
employee of the Company or of any subsidiary or affiliate of the Company
("Director") shall be entitled to participate in the Plan.

     5. Grants under the Plan. All Options granted under the Plan shall be
non-statutory options, not entitled to special tax treatment under Section 422
of the Internal Revenue Code of 1986, as amended (the "Code"). The number of
shares of Common Stock available for grants under the Plan shall not exceed
150,000 shares, subject to adjustment as provided in Section7. The shares with
respect to which particular Option has been granted are 

<PAGE>
                                      -2-


hereinafter referred to as "Optioned Shares." The written agreement evidencing
each Option granted under the Plan (the "Agreement") shall be dated as of the
applicable date of grant. Each Director accepting an Option grant shall execute
and return a copy of the Agreement to the Company. If any outstanding Option
shall terminate for any reason without having been exercised in full, the shares
applicable to the unexercised portion of such Option shall again become
available under the Plan. Either authorized and unissued shares or treasury
shares may be delivered under the Plan.

     6. Stock Options.

     (a) Initial Grants. On the Adoption Date (which shall be the date of grant
for purposes of paragraphs 6(c), (d) and (e)) of the Plan, each Director shall
be granted an Option to purchase that number of shares of Common Stock equal to
10,000 minus the number of shares of Common stock with respect to which options
have been previously granted to such Director (without regard to the status of
such Director at the time of any such prior grant, whether any such prior grant
was made pursuant to another plan of the company or any other circumstances of
any such prior grant), subject to the approval of the Plan by the Company's
stockholders at the 1992 annual meeting. Each person who becomes a Director for
the first time after the Effective Date (as defined below) shall be granted an
Option on the six-month anniversary of the date such person becomes a Director
to purchase that number of shares of Common Stock equal to 10,000 minus the
number of shares of Common Stock with respect to which options have been
previously granted to such Director (without regard to the status of such
Director at the time of any such prior grant, whether any such prior grant was
made pursuant to another plan of the Company or any other circumstances of any
such prior grant).

     (b) Regular Annual Grants. On each date that the Company holds its annual
meeting of stockholders commencing with the 1993 calendar year, immediately
after the annual election of directors, each Director then in office (other than
those Directors first elected at such meeting) will receive a grant of an Option
to purchase 1,000 shares, provided that no Director will receive under this Plan
Options to purchase a total of more than 25,000 shares.

     (c) Option Exercise Price. The per share price to be paid by the Director
at the time an Option is exercised shall be 100% of the fair market value of the
Common Stock on the date of grant. "Fair market value" shall be determined as
follows:

          (i) If the Common Stock is not at the time listed or admitted to
     trading on any stock exchange but is traded in the over-the-counter market,
     the fair market value shall be the closing selling price per share of
     Common Stock on the date in question, as such price is reported by the
     National Association of Securities Dealers through its NASDAQ National
     Market System or any successor system. If there is no reported 


<PAGE>
                                      -3-


     closing selling price for Common Stock on the date in question, then the
     closing selling price on the last preceding date for which such quotation
     exists shall be determinative of fair market value.

          (ii) If the Common Stock is at the time listed or admitted to trading
     on any stock exchange, then the fair market value shall be the closing
     selling price per share of Common Stock on the date in question on the
     stock exchange which is the primary market for the Common Stock, as such
     price is officially quoted on such exchange. If there is no reported sale
     of Common Stock on such exchange on the date in question, then the fair
     market value shall be the closing selling price on the exchange on the last
     preceding date for which such quotation exists.

     (d) Maximum Term of Option. Each Option shall have a maximum term of ten
(10) years from the date of grant.

     (e) Date of Exercise. Provided that an optionee hereunder (an "Optionee")
remains a Director, and except as otherwise provided in paragraph 8(a),

          (i) the Options granted in Section 6(a) hereof shall become
     exercisable in accordance with the following schedule:

          (A)  With respect to Options granted pursuant to the first sentence of
               Section 6(a) hereof, each such Option shall become exercisable
               with respect to 20% of the Optioned Shares on the date of grant;

          (B)  Each Option shall become exercisable with respect to 20% (or, in
               the case of Options referred to in clause (A) above, an
               additional 20%) of the Optional Shares after the expiration of
               one year from the date of grant;

          (C)  Each Option shall become exercisable with respect to an
               additional 20% of the Optional Shares after the expiration of two
               years from the date of grant;

          (D)  Each Option shall become exercisable with respect to an
               additional 20% of the Optioned Shares after the expiration of
               three years from the date of grant;

          (E)  Each Option shall become exercisable with respect to an
               additional 20% (or, in the case of Options referred to in clause
               (A) above, the remaining 20%) of the Optional Shares after the
               expiration of four years from the date of grant;


<PAGE>
                                      -4-


          (F)  With respect to Options other than those referred to in clause
               (A) above, each such Option shall become exercisable with respect
               to the remaining 20% of the Optioned Shares after the expiration
               of five years from the date of grant; and

          (ii) the Options granted in Section 6(b) hereof shall become
     exercisable on the date of grant.

     Exercisable installments may be exercised in whole or in part and, to the
extent not exercised, shall accumulate and be exercisable at any time on or
before the Expiration Date or sooner termination of the Option term.

     (f) Accelerated Termination of Option Term. The option term with respect to
a particular Option granted hereunder shall terminate (and such Option shall
cease to be exercisable) prior to the specified expiration date thereof (the
"Expiration Date") should one of the following provisions become applicable:

          (i) Except as otherwise provided in subparagraphs (ii), (iii) and (iv)
     below, should Optionee cease to be a Director at any time during the option
     term, then Optionee shall have up to a three (3) month period commencing
     with the date of such cessation of Director status in which to exercise
     this Option, but in no event shall this Option be exercisable at any time
     after the Expiration Date. During such limited period of exercisability,
     the Option may not be exercised for more than the number of Optioned Shares
     (if any) for which it is exercisable at the date of Optionee's cessation of
     Director status. Upon the expiration of such limited period of
     exercisability or (if earlier) upon the Expiration Date, the Option shall
     terminate and cease to be outstanding.

          (ii) Should Optionee die while such Option is outstanding, then the
     personal representative of Optionee's estate or the person or persons to
     whom the Option is transferred shall have the right to exercise this
     Option, but only with respect to that number of Optioned shares (if any)
     for which Option is exercisable on the date of Optionee's death. Such right
     shall lapse and the Option shall cease to be exercisable upon the earlier
     of (A) the expiration of the one (1) year period measured from the date of
     Optionee's death or (B) the specified Expiration Date of the Option term.

          (iii) Should Optionee become permanently disabled and cease by reason
     thereof to be a Director at any time during the Option term, then Optionee
     shall have a period of twelve (12) months (commencing with the date of such
     cessation of Director status) during which to exercise such Option;
     provided, however, that in no event shall the Option be exercisable at any
     time after the Expiration Date. During such limited period of
     exercisability, the Option may not be exercised for more that the number of

<PAGE>
                                      -5-


     Optioned Shares (if any) for which this Option is exercisable at the date
     of Optionee's cessation of Director status. Upon the expiration of such
     limited period of exercisability or (if earlier) upon the Expiration Date,
     the Option shall terminate and cease to be outstanding. Optionee shall be
     deemed to be permanently disabled if Optionee is, by reason of any
     medically determinable physical or mental impairment expected to result in
     death or to be of continuous duration of not less than 12 consecutive
     months or more, unable to perform his/her usual duties as a director of the
     Company.

          (iv) Should Optionee's status as a Director be terminated on account
     of any act of (A) fraud or intentional misrepresentation, or (B)
     embezzlement, misappropriation or conversion of assets or opportunities of
     the Company, or any unauthorized disclosure of confidential information or
     trade secrets of the Company, such Option shall terminate and cease to be
     exercisable immediately upon the date of such termination of Director
     status.

     (g) Method of Exercise. An Option may be exercised with respect to all or
any part of the shares of Common Stock for which such Option is at the time
exercisable. Each notice of exercise shall be accompanied by the full purchase
price of the shares being purchased, with such payment to be made in cash or by
check.

     (h) Transferability. Options are transferable and assignable to the spouse
of the Optionee or a descendent of the Optionee (any such spouse or descendent,
an "Immediate Family Member") or a corporation, partnership, limited liability
company or trust so long as all of the shareholders, partners, members or
beneficiaries thereof, as the case may be, are either the Optionee or an
Immediate Family Member of the Optionee, provided that (i) there may be no
consideration for any such transfer and (ii) subsequent transfers or transferred
options will be prohibited other than by will, by the laws of descent and
distribution or pursuant to a "qualified domestic relations order" as such term
is defined by the Code or the Employee Retirement Income Security Act of 1974
("ERISA"). Following transfer, any such options will continue to be subject to
the same terms and conditions as were applicable immediately prior to transfer,
provided that for purposes of the option agreement the term "Optionee" will
refer to the transferee.

     7. Adjustment Upon Changes in Capitalization

     (a) If the number of shares of the Company as a whole are increased,
decreased or changed into, or exchanged for, a different number or kind of
shares or securities of the Company, whether through reclassification, stock,
dividend, stock split, combination of shares, exchange of shares, change in
corporate structure or the like, an appropriate and proportionate adjustment
shall be made in the number and kind of shares subject to the Plan, and in the
number, kind and per share exercise price of shares subject to unexercised
Options or portions thereof granted prior to any such change. Any such

<PAGE>
                                      -6-


adjustment in an outstanding Option, however, shall be made without a change in
the total price applicable to the unexercised portion of the Option but with a
corresponding adjustment in the price for each share covered by the Option.

     (b) If the Company is the surviving entity in any merger or other business
combination, then an Option shall be appropriately adjusted to apply and pertain
to the number and class of securities which the holder of the number of shares
of Common Stock subject to an Option immediately prior to such merger or other
business combination would have been entitled to receive in the consummation of
such merger or other business combination, and appropriate adjustment shall be
made to the option price payable per share, provided the aggregate option price
shall remain the same.

     8. Corporate Transaction.

     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Company is not the surviving
     entity, except for a transaction the principal purpose of which is to
     change the State of the Company's incorporation,

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Company, or

          (iii) any other business combination in which fifty percent (50%) or
     more of the Company's outstanding voting stock is transferred to different
     holders in a single transaction or a series of related transactions,

then the exercisablity of an Option shall automatically be accelerated so that
such Option may be exercised for any or all of the shares of Common Stock
subject to such Option. No such acceleration of exercise dates shall occur,
however, if and to the extent the terms of any agreement relating to such
Corporate Transaction provide as a prerequisite to the consummation of such
Corporate Transaction that outstanding options purchase Common Stock (including
an Option issued pursuant to this Plan) are to be assumed by the successor
corporation or parent thereof or are to be replaced with options to purchase
shares of capital stock of the successor corporation or parent thereof. In any
such case, an appropriate adjustment as to the number and kind of shares and the
per share exercise prices shall be made. No fractional shares of stock shall be
issued under the Plan on account of any adjustment specified above. Upon the
consummation of the Corporate Transaction, an Option shall, to the extent not
previously exercised or assumed by the successor corporation or its parent
company, terminate and cease to be exercisable.


<PAGE>
                                      -7-


     (b) This Plan shall not in any way affect the right of the company to
adjust, reclassify, reorganize or otherwise make changes in its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     9. Amendment and Termination of Plan. The Board may make such amendments to
the Plan and to any Agreements hereunder as it shall deem advisable; provided,
however, that the Board may not, without further approval by the affirmative
votes of the holders of a majority of the securities of the Company present, or
represented, and entitled to vote at a stockholders meeting duly held in
accordance with applicable laws, increase the number of shares as to which
Options may be granted under this Plan (except as otherwise permitted in
paragraph 8(a) hereof), materially increase the benefits accruing to
participants under this Plan or materially modify the requirements as to
eligibility for participation under this Plan. In addition, the Board may not
amend the Plan or Agreement hereunder more than once every six months, other
than to comport with changes in the Code or the rules thereunder. The Board may
terminate the Plan at any time within its absolute discretion. No such
termination, other than that provided in Section8(a) hereof, shall in any way
affect any Option then outstanding.

     10. Miscellaneous Provisions. Neither the Plan nor any action taken
hereunder shall be construed as giving any Director any right to be nominated
for re-election to the Board. The Plan shall be governed by the laws of the
State of California.

     11. Effective Date. The Plan shall, subject to the approval of the
stockholders at the 1992 annual meeting, be effective as of February 20, 1992
(the "Effective Date").



This document is to be used for initial grants to new directors


                             Stock Option Agreement

                           Under the XOMA Corporation

                        1992 Directors Stock Option Plan



(A)         Optionee:

(B)         Grant Date:                  (E)       Expiration Date:

(C)         Shares:                      (F)       Exercise Price:
            10,000 shares                          $   per share

(D)         Share Installments:          (G)       Option Type:
            Option becomes exercis-                Non-Qualified Stock Option
            able in five equal, an-
            nual installments, be-
            ginning 1 year from
            Grant Date

     Subject to the terms of the XOMA Corporation 1992 Directors Stock Option
Plan, as amended and restated through October 30, 1996 (the "Plan") and to the
terms and conditions set forth in this agreement (the "Agreement"), XOMA
Corporation (the "Corporation") has granted you, as of the Grant Date shown in
item (B) above, a non-qualified stock option (not entitled to special tax
treatment under Section 422 of the Internal Revenue Code of 1986, as amended
(the "Code")) to purchase the number of shares of the Corporation's Common Stock
shown in item (C) above (the "Optioned Shares") at the Exercise Price shown in
item (F) above.

     The details of your option are as follows:

     1. Term. This option has a maximum term of ten years measured from the
Grant Date and will, unless sooner terminated in accordance with Section 4 or
Subsection 6(a) hereof, expire on the Expiration Date shown in item (E) above.
Upon the Expiration Date or upon the sooner termination of this option under
Section 4 or Subsection 6(a), this option will cease to be exercisable and have
no further force or effect whatsoever.


<PAGE>
                                      -2-


     2. Transferability. This option is transferable and assignable by you to
your spouse or descendent (any such spouse or descendent, an "Immediate Family
Member") or a corporation, partnership, limited liability company or trust so
long as all of the shareholders, partners, members or beneficiaries thereof, as
the case may be, are either you or an Immediate Family Member, provided that
there may be no consideration for any such transfer, and, following transfer,
(i) subsequent transfers of this option will be prohibited other than by will or
the laws of descent and distribution, and (ii) this option will continue to be
subject to the same terms and conditions as were applicable immediately prior to
transfer, provided that for purposes of this Agreement any references to "you"
will refer to the transferee.

     3. Exercise Schedule. Provided that you remain a member of the Board of
Directors of the Corporation who is not a full or part-time employee of the
Corporation or of any subsidiary or affiliate of the Corporation (a "Director"),
and except as otherwise provided in Section 6(a), the option granted herein will
become exercisable in accordance with the following schedule:

     (a) This option is exercisable with respect to 20% of the Optioned Shares
after the expiration of one year from the Grant Date;

     (b) This option is exercisable with respect to an additional 20% of the
Optioned Shares after the expiration of two years from the Grant Date;

     (c) This option is exercisable with respect to an additional 20% of the
Optioned Shares after the expiration of three years from the Grant Date;

     (d) This option is exercisable with respect to an additional 20% of the
Optioned Shares after the expiration of four years from the Grant Date; and

     (e) This option is exercisable with respect to the remaining 20% of the
Optioned Shares after the expiration of five years from the Grant Date.

     Exercisable installments may be exercised in whole or in part in increments
of 25 or more shares and, to the extent not exercised, will accumulate and be
exercisable at any time on or before the Expiration Date or sooner termination
of the option term.


<PAGE>
                                      -3-


     4. Accelerated Termination of Option Term. The option term specified in
Section 1 will terminate (and this option will cease to be exercisable) prior to
the Expiration Date should one of the following provisions become applicable:

     (a) Except as otherwise provided in Subsections (b), (c) and (d) below, if
you cease to be a Director at any time during the option term, then you will
have up to three months commencing with the date of such cessation of Director
status in which to exercise this option, but in no event will this option be
exercisable at any time after the Expiration Date. During such limited period of
exercisability, this option may not be exercised for more than the number of
Optioned Shares (if any) for which it is exercisable at the date of your
cessation of Director status. Upon the expiration of such limited period of
exercisability or (if earlier) upon the Expiration Date, this option will
terminate and cease to be outstanding.

     (b) If you die while this option is outstanding, then the personal
representative of your estate or the person or persons to whom the option is
transferred pursuant to your will or in accordance with the laws of descent and
distribution will have the right to exercise this option, but only with respect
to the number of Optioned Shares (if any) for which it is exercisable at the
date of your death. Such right will lapse and this option will cease to be
exercisable upon the earlier of (i) the expiration of the one-year period
measured from the date of your death or (ii) the Expiration Date.

     (c) If you become permanently disabled and cease by reason thereof to be a
Director at any time during the option term, then you will have a period of
twelve months (commencing with the date of such cessation of Director status)
during which to exercise this option; provided, however, that in no event will
this option be exercisable at any time after the Expiration Date. During such
limited period of exercisability, this option may not be exercised for more than
the number of Optioned Shares (if any) for which this option is exercisable at
the date of your cessation of Director status. Upon the expiration of such
limited period of exercisability or (if earlier) upon the Expiration Date, this
option will terminate and cease to be outstanding. You will be deemed to be
permanently disabled if you are, by reason of any medically determinable
physical or mental impairment expected to result in death or to be of continuous
duration of not less than 


<PAGE>
                                      -4-


twelve consecutive months or more, unable to perform your usual duties as a
Director of the Corporation.

     (d) If your status as a Director is terminated on account of any act of (i)
fraud or intentional misrepresentation or (ii) embezzlement, misappropriation or
conversion of assets or opportunities of the Corporation, or any unauthorized
disclosure of confidential information or trade secrets of the Corporation, this
option will terminate and cease to be exercisable immediately upon the date of
such termination of Director status.

     5. Adjustment Upon Changes in Capitalization.

     (a) If the number of shares of the Corporation as a whole is increased,
decreased or changed into, or exchanged for, a different number or kind of
shares or securities of the Corporation, whether through reclassification, stock
dividend, stock split, combination of shares, exchange of shares, change in
corporate structure or the like, an appropriate and proportionate adjustment
will be made in the number, kind, and per share exercise price of shares subject
to unexercised options or portions thereof granted prior to any such change. Any
such adjustment in an outstanding portion, however, will be made without a
change in the total price applicable to the unexercised portion of the option,
but with a corresponding adjustment in the price of each share covered by the
option.

     (b) If the Corporation is the surviving entity in any merger or other
business combination, then this option will be appropriately adjusted to apply
and pertain to the number and class of securities which the holder of the number
of shares of the Corporation's Common Stock subject to this option immediately
prior to such merger or other business combination would have been entitled to
receive in the consummation of such merger or other business combination, and an
appropriate adjustment will be made to the Exercise Price payable per share,
provided the aggregate Exercise Price will remain the same.

     6. Corporate Transaction.

     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Corporation is not the
     surviving entity, except for a transaction the 


<PAGE>
                                      -5-


     principal purpose of which is to change the State of the Corporation's
     incorporation,

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Corporation, or

          (iii) any other business combination in which fifty percent (50%) or
     more of the Corporation's outstanding voting stock is transferred to
     different holders in a single transaction or a series of related
     transactions,

then the exercisability of this option will automatically be accelerated so that
such option may be exercised simultaneously with consummation of such Corporate
Transaction for any or all of the shares of the Corporation's Common stock
subject to this option. No such acceleration of exercise dates will occur,
however, if and to the extent the terms of any agreement relating to such
Corporate Transaction provide as a prerequisite to the consummation of such
Corporate Transaction that outstanding options to purchase the Corporation's
Common Stock (including this option) are to be assumed by the successor
corporation or parent thereof or are to be replaced with options to purchase
shares of capital stock of the successor corporation or parent thereof. In any
such case, an appropriate adjustment as to the number and kind of shares and the
per share exercise prices will be made. No fractional shares of stock will be
issued on account of any adjustment specified above. Immediately following the
consummation of the Corporate Transaction, this option will, to the extent not
previously exercised or assumed by the successor corporation or its parent
company, terminate and cease to be exercisable.

     (b) This Agreement will not in any way affect the right of the Corporation
to adjust, reclassify, reorganize or otherwise make changes in its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     7. Privilege of Stock Ownership. You will not have any rights of a
stockholder of the Corporation with respect to the Optioned Shares until you
have exercised the option, paid the Exercise Price and been issued a stock
certificate for the purchased shares.

     8. Manner of Exercising Option.

     (a) In order to exercise this option with respect to all or any part of the
Optioned Shares for which this option is at the time exercisable, you (or in the
case of exercise after 


<PAGE>
                                      -6-


your death, your executor, administrator, heir or legatee, as the case may be)
must take the following actions:

          (i) Provide the Secretary of the Corporation with written notice of
     such exercise, specifying the number of Optioned Shares with respect to
     which the option is being exercised.

          (ii) Pay the Exercise Price in full, in cash or by check payable to
     the Corporation's order, for the Optioned Shares being purchased.

          (iii) Furnish to the Corporation appropriate documentation that the
     person or persons exercising the option, if other than you, have the right
     to exercise this option.

     (b) In no event may this option be exercised for any fractional shares.

     9. Compliance with Laws and Regulations.

     (a) The exercise of this option and the issuance of Optioned Shares upon
such exercise will be subject to compliance by the Corporation and by you with
all applicable requirements of law relating thereto and with all applicable
regulations of any stock exchange on which shares of the Corporation's Common
Stock may be listed at the time of such exercise and issuance.

     (b) In connection with the exercise of this option, you will execute and
deliver to the Corporation such representations in writing as may be requested
by the Corporation in order for it to comply with the applicable requirements of
Federal and State securities law.


     10. Restrictive Legends. If and to the extent any Optioned Shares acquired
under this option are not registered under the Securities Act of 1933, the stock
certificates for such Optioned Shares will be endorsed with restrictive legends,
including (without limitation) the following:

          "The Shares represented by this certificate have not been registered
          under the Securities Act of 1933. The shares have been acquired for
          investment and may not be sold or offered for sale in the absence of
          (a) an effective registration statement for the shares 


<PAGE>
                                      -7-


          under such Act, (b) a 'no action' letter of the Securities and
          Exchange Commission with respect to such sale or offer, or (c) an
          opinion of counsel to the Company that registration under such Act is
          not required with respect to such sale or offer."

     11. Successors and Assigns. Except to the extent otherwise provided in
Section 2 and Subsection 6(a), the provisions of this Agreement will inure to
the benefit of, and be binding upon, your successors, administrators, heirs,
legal representatives and assigns and the successors and assigns of the
Corporation.

     12. Liability of the Corporation.

     (a) If the Optioned Shares covered by this Agreement exceed, as of the
Grant Date, the number of shares of the Corporation's Common Stock which may
without stockholder approval be issued under the Plan, then this option will be
void with respect to such excess shares unless stockholder approval of an
amendment sufficiently increasing the number of shares of the Corporation's
Common Stock issuable under the Plan is obtained in accordance with the
provisions of the Plan.

     (b) The inability of the Corporation to obtain approval from any regulatory
body having authority deemed by the Corporation to be necessary to the lawful
issuance and sale of any Common Stock pursuant to this option will relieve the
Corporation of any liability in respect of the non-issuance or sale of such
stock as to which such approval will not have been obtained.

     13. No Right to Nomination. Neither this Agreement nor any action taken
hereunder will be construed as giving you any right to be nominated for
re-election to the Board of Directors of the Corporation.

     14. Notices. Any notice required to be given or delivered to the
Corporation under the terms of this Agreement will be in writing and addressed
to the Corporation in care of its Secretary at its corporate offices. Any notice
required to be given or delivered to you will be in writing and addressed to you
at the address indicated below your signature line herein. All notices will be
deemed to be given or delivered upon personal delivery or upon deposit in the
U.S. mail, postage prepaid and properly addressed to the party to be notified.


<PAGE>
                                      -8-


     15. Construction. This Agreement and the option evidenced hereby are made
and granted pursuant to the Plan and are in all respects limited by and subject
to the express terms and provisions of the Plan. Any dispute regarding the
interpretation of this Agreement will be submitted to the Plan Administrator (as
that term is defined in the Plan) for resolution. The decision of the Plan
Administrator will be final, binding and conclusive. Questions regarding this
option or the Plan should be referred to the Paralegal Assistant in the Legal
Department of the Corporation.

     16. Governing Law. The interpretation, performance, and enforcement of this
Agreement will be governed by the laws of the State of California.


                           XOMA CORPORATION


                           By:
                                    John L. Castello
                                    Chairman of the Board,
                                    President & Chief Executive
                                      Officer


                           Dated:


     I hereby agree to be bound by the terms and conditions of this Agreement
and the Plan.

                            By:


                            Dated:


<PAGE>
                                      -9-


     If the optionee resides in California or another community property
jurisdiction, I, as the optionee's spouse, also agree to be bound by the terms
and conditions of this Agreement and the Plan.


                            By:


                            Dated:


This document is to be used for annual grants to existing directors


                             Stock Option Agreement

                           Under the XOMA Corporation

                        1992 Directors Stock Option Plan



(A)         Optionee:

(B)         Grant Date:                   (E)       Expiration Date:

(C)         Shares:                       (F)       Exercise Price:
            1,000 shares                            $   per share

(D)         Share Installments:           (G)       Option Type:
            Option is fully                         Non-Qualified Stock Option
            exercisable

     Subject to the terms of the XOMA Corporation 1992 Directors Stock Option
Plan, as amended and restated through October 30, 1996 (the "Plan") and to the
terms and conditions set forth in this agreement (the "Agreement"), XOMA
Corporation (the "Corporation") has granted you, as of the Grant Date shown in
item (B) above, a non-qualified stock option (not entitled to special tax
treatment under Section 422 of the Internal Revenue Code of 1986, as amended
(the "Code")) to purchase the number of shares of the Corporation's Common Stock
shown in item (C) above (the "Optioned Shares") at the Exercise Price shown in
item (F) above.

     The details of your option are as follows:

     1. Term. This option has a maximum term of ten years measured from the
Grant Date and will, unless sooner terminated in accordance with Section 4 or
Subsection 6(a) hereof, expire on the Expiration Date shown in item (E) above.
Upon the Expiration Date or upon the sooner termination of this option under
Section 4 or Subsection 6(a), this option will cease to be exercisable and have
no further force or effect whatsoever.

     2. Transferability. This option is transferable and assignable by you to
your spouse or descendent (any such spouse or descendent, an "Immediate Family
Member") or a corporation, partnership, limited liability company or trust so
long as all of the shareholders, partners, members or beneficiaries thereof, as
the case may be, are either you or an Immediate Family Member, provided that
there may be no consideration for 


<PAGE>
                                      -2-


any such transfer, and, following transfer, (i) subsequent transfers of this
option will be prohibited other than by will or the laws of descent and
distribution, and (ii) this option will continue to be subject to the same terms
and conditions as were applicable immediately prior to transfer, provided that
for purposes of this Agreement any references to "you" will refer to the
transferee.

     3. Exercise Schedule. The option granted herein is exercisable with respect
to 100% of the Optioned Shares beginning on the Grant Date and may be exercised
in whole or in part, and to the extent not exercised, will be exercisable at any
time on or before the Expiration Date or sooner termination of the option term.

     4. Accelerated Termination of Option Term. The option term specified in
Section 1 will terminate (and this option will cease to be exercisable) prior to
the Expiration Date should one of the following provisions become applicable:

     (a) Except as otherwise provided in Subsections (b), (c) and (d) below, if
you cease to be a member of the Board of Directors of the Corporation who is not
a full or part-time employee of the Corporation or of any subsidiary or
affiliate of the Corporation (a "Director") at any time during the option term,
then you will have up to three months commencing with the date of such cessation
of Director status in which to exercise this option, but in no event will this
option be exercisable at any time after the Expiration Date. Upon the expiration
of such limited period of exercisability or (if earlier) upon the Expiration
Date, this option will terminate and cease to be outstanding.

     (b) If you die while this option is outstanding, then the personal
representative of your estate or the person or persons to whom the option is
transferred pursuant to your will or in accordance with the laws of descent and
distribution will have the right to exercise this option. Such right will lapse
and this option will cease to be exercisable upon the earlier of (i) the
expiration of the one-year period measured from the date of your death or (ii)
the Expiration Date.

     (c) If you become permanently disabled and cease by reason thereof to be a
Director at any time during the option term, then you will have a period of
twelve months (commencing with the date of such cessation of Director status)
during which to exercise this option; provided, however, that in no event will
this option be exercisable at any time after the Ex-


<PAGE>
                                      -3-


piration Date. Upon the expiration of such limited period of exercisability or
(if earlier) upon the Expiration Date, this option will terminate and cease to
be outstanding. You will be deemed to be permanently disabled if you are, by
reason of any medically determinable physical or mental impairment expected to
result in death or to be of continuous duration of not less than twelve
consecutive months or more, unable to perform your usual duties as a Director of
the Corporation.

     (d) If your status as a Director is terminated on account of any act of (i)
fraud or intentional misrepresentation or (ii) embezzlement, misappropriation or
conversion of assets or opportunities of the Corporation, or any unauthorized
disclosure of confidential information or trade secrets of the Corporation, this
option will terminate and cease to be exercisable immediately upon the date of
such termination of Director status.

     5. Adjustment Upon Changes in Capitalization.

     (a) If the number of shares of the Corporation as a whole is increased,
decreased or changed into, or exchanged for, a different number or kind of
shares or securities of the Corporation, whether through reclassification, stock
dividend, stock split, combination of shares, exchange of shares, change in
corporate structure or the like, an appropriate and proportionate adjustment
will be made in the number, kind, and per share exercise price of shares subject
to unexercised options or portions thereof granted prior to any such change. Any
such adjustment in an outstanding portion, however, will be made without a
change in the total price applicable to the unexercised portion of the option,
but with a corresponding adjustment in the price of each share covered by the
option.

     (b) If the Corporation is the surviving entity in any merger or other
business combination, then this option will be appropriately adjusted to apply
and pertain to the number and class of securities which the holder of the number
of shares of the Corporation's Common Stock subject to this option immediately
prior to such merger or other business combination would have been entitled to
receive in the consummation of such merger or other business combination, and an
appropriate adjustment will be made to the Exercise Price payable per share,
provided the aggregate Exercise Price will remain the same.

     6. Corporate Transaction.


<PAGE>
                                      -4-


     (a) In the event of one or more of the following transactions ("Corporate
Transaction"):

          (i) a merger or acquisition in which the Corporation is not the
     surviving entity, except for a transaction the principal purpose of which
     is to change the State of the Corporation's incorporation,

          (ii) the sale, transfer or other disposition of all or substantially
     all of the assets of the Corporation, or

          (iii) any other business combination in which fifty percent (50%) or
     more of the Corporation's outstanding voting stock is transferred to
     different holders in a single transaction or a series of related
     transactions,

then the exercisability of this option will automatically be accelerated so that
such option may be exercised simultaneously with consummation of such Corporate
Transaction for any or all of the shares of the Corporation's Common stock
subject to this option. No such acceleration of exercise dates will occur,
however, if and to the extent the terms of any agreement relating to such
Corporate Transaction provide as a prerequisite to the consummation of such
Corporate Transaction that outstanding options to purchase the Corporation's
Common Stock (including this option) are to be assumed by the successor
corporation or parent thereof or are to be replaced with options to purchase
shares of capital stock of the successor corporation or parent thereof. In any
such case, an appropriate adjustment as to the number and kind of shares and the
per share exercise prices will be made. No fractional shares of stock will be
issued on account of any adjustment specified above. Immediately following the
consummation of the Corporate Transaction, this option will, to the extent not
previously exercised or assumed by the successor corporation or its parent
company, terminate and cease to be exercisable.

     (b) This Agreement will not in any way affect the right of the Corporation
to adjust, reclassify, reorganize or otherwise make changes in its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     7. Privilege of Stock Ownership. You will not have any rights of a
stockholder of the Corporation with respect to the Optioned Shares until you
have exercised the option, paid the Exercise Price and been issued a stock
certificate for the purchased shares.


<PAGE>
                                      -5-


     8. Manner of Exercising Option.

     (a) In order to exercise this option with respect to all or any part of the
Optioned Shares for which this option is at the time exercisable, you (or in the
case of exercise after your death, your executor, administrator, heir or
legatee, as the case may be) must take the following actions:

          (i) Provide the Secretary of the Corporation with written notice of
     such exercise, specifying the number of Optioned Shares with respect to
     which the option is being exercised.

          (ii) Pay the Exercise Price in full, in cash or by check payable to
     the Corporation's order, for the Optioned Shares being purchased.

          (iii) Furnish to the Corporation appropriate documentation that the
     person or persons exercising the option, if other than you, have the right
     to exercise this option.

     (b) In no event may this option be exercised for any fractional shares.

     9. Compliance with Laws and Regulations.

     (a) The exercise of this option and the issuance of Optioned Shares upon
such exercise will be subject to compliance by the Corporation and by you with
all applicable requirements of law relating thereto and with all applicable
regulations of any stock exchange on which shares of the Corporation's Common
Stock may be listed at the time of such exercise and issuance.

     (b) In connection with the exercise of this option, you will execute and
deliver to the Corporation such representations in writing as may be requested
by the Corporation in order for it to comply with the applicable requirements of
Federal and State securities law.

     10. Restrictive Legends. If and to the extent any Optioned Shares acquired
under this option are not registered under the Securities Act of 1933, the stock
certificates for such Optioned Shares will be endorsed with restrictive legends,
including (without limitation) the following:

          "The Shares represented by this certificate have not been registered
     under the Securities Act of 1933. 


<PAGE>
                                      -6-


     The shares have been acquired for investment and may not be sold or offered
     for sale in the absence of (a) an effective registration statement for the
     shares under such Act, (b) a 'no action' letter of the Securities and
     Exchange Commission with respect to such sale or offer, or (c) an opinion
     of counsel to the Company that registration under such Act is not required
     with respect to such sale or offer."

     11. Successors and Assigns. Except to the extent otherwise provided in
Section 2 and Subsection 6(a), the provisions of this Agreement will inure to
the benefit of, and be binding upon, your successors, administrators, heirs,
legal representatives and assigns and the successors and assigns of the Company.

     12. Liability of the Corporation.

     (a) If the Optioned Shares covered by this Agreement exceed, as of the
Grant Date, the number of shares of the Corporation's Common Stock which may
without stockholder approval be issued under the Plan, then this option will be
void with respect to such excess shares unless stockholder approval of an
amendment sufficiently increasing the number of shares of the Corporation's
Common Stock issuable under the Plan is obtained in accordance with the
provisions of the Plan.

     (b) The inability of the Corporation to obtain approval from any regulatory
body having authority deemed by the Corporation to be necessary to the lawful
issuance and sale of any Common Stock pursuant to this option will relieve the
Corporation of any liability in respect of the non-issuance or sale of such
stock as to which such approval will not have been obtained.

     13. No Right to Nomination. Neither this Agreement nor any action taken
hereunder will be construed as giving you any right to be nominated for
re-election to the Board of Directors of the Corporation.

     14. Notices. Any notice required to be given or delivered to the
Corporation under the terms of this Agreement will be in writing and addressed
to the Corporation in care of its Secretary at its corporate offices. Any notice
required to be given or delivered to you will be in writing and addressed to you
at the address indicated below your signature line herein. All notices will be
deemed to be given or delivered upon per-


<PAGE>
                                      -7-


sonal delivery or upon deposit in the U.S. mail, postage prepaid and properly
addressed to the party to be notified.

     15. Construction. This Agreement and the option evidenced hereby are made
and granted pursuant to the Plan and are in all respects limited by and subject
to the express terms and provisions of the Plan. Any dispute regarding the
interpretation of this Agreement will be submitted to the Plan Administrator (as
that term is defined in the Plan) for resolution. The decision of the Plan
Administrator will be final, binding and conclusive. Questions regarding this
option or the Plan should be referred to the Paralegal Assistant in the Legal
Department of the Corporation.

     16. Governing Law. The interpretation, performance, and enforcement of this
Agreement will be governed by the laws of the State of California.


                             XOMA CORPORATION


                             By:
                                 John L. Castello
                                 Chairman of the Board,
                                 President & Chief Executive
                                   Officer


                             Dated:


     I hereby agree to be bound by the terms and conditions of this Agreement
and the Plan.


                             By:


                             Dated:

     If the optionee resides in California or another community property
jurisdiction, I, as the optionee's spouse, also agree to be bound by the terms
and conditions of this Agreement and the Plan.


                             By:


                             Dated:





                                XOMA Corporation

                     Management Incentive Compensation Plan

I.       Introduction and Summary.

         This document describes the XOMA Corporation Management Incentive
Compensation Plan (the "Plan"), as approved by the Board of Directors. The Plan
became effective on July 1, 1993 and was amended as of October 27, 1993. Subject
to the ability of the Board of Directors to terminate the Plan at any time, the
Plan applies to fiscal years ending December 31, 1993 and each December 31
thereafter.

         Officers, employees who have the title of Director or are in salary
grades E8 and above and report directly to an officer, and additional
discretionary participants ("Discretionary Participants") determined by the
Chief Executive Officer ("CEO") to be critical to the achievement of Corporate
Objectives established by the Board of Directors, are eligible to participate in
this Plan and, depending on their performance and that of the corporation, earn
incentive compensation ("Incentive Compensation") (Article III contains the
definitions of certain terms not otherwise defined in the places such terms
first appear in this Plan.) The CEO shall designate those eligible employees who
will participate in the Plan. Employees receiving promotions, and new employees
joining XOMA during a Plan Period, who thereby meet the eligibility criteria for
participation in the Plan, will be considered at the discretion of the CEO for
participation in the Plan on a pro rata basis. The CEO will not participate in
the Plan.

         After the conclusion of each applicable Plan Period, the Board of
Directors and the Compensation Committee of the Board of Directors (the
"Compensation Committee") will make a determination as to the performance of
XOMA and Plan participants in meeting Corporate Objectives as well as individual
objectives. Prior to the commencement of each Plan Period, the Board of
Directors acting on the advice of the Compensation Committee, will establish a
target Incentive Compensation Pool ("Target Incentive Compensation Pool"). The
Target Incentive Compensation Pool will be expressed as a percentage of the
aggregate annual Base Salaries of all participants in the Plan for the
applicable Plan Period. Awards to individual participants will vary depending on
(1) the achievement of Corporate Objectives; (2) the size of the Target
Incentive Compensation Pool; (3) the individual's Base Salary; and (4) the
individual's performance during the applicable Plan Period and expected ongoing
contribution to XOMA. Awards may exceed or be lower than the Target Incentive
Compensation Pool on the basis of the calculation of the

                                        1
<PAGE>
extent to which XOMA's Corporate Objectives have been met as set forth in the
Explanatory Note to Schedule I attached hereto.

         Individual awards will be granted in cash and/or shares of XOMA common
stock based on the average market value of the common stock for the ten trading
days prior to the date of the award. Individual awards will vest over a
three-year period with 50% of each award payable on a distribution date set by
the Board of Directors acting in part on the advice of the CEO and the
Compensation Committee and expected to be in February or March of the year
succeeding the Plan Period and 25% of the award payable on each of the next two
annual distribution dates as long as the individual continues to be employed by
XOMA and continues to be a Plan participant. The portion of each award to be
paid on the first distribution date following a Plan Period will be comprised of
50% cash and 50% in shares of XOMA common stock based on the market value
formula set forth above. For the balance of the award expected to be paid in
successive years, participants will be asked to make a one-time, irrevocable
choice prior to December 31 of the year succeeding the Plan Period, as to
whether the balance of the award should be paid in cash or shares of XOMA common
stock. Failure to exercise the option or to meet the December 31 deadline will
result in the common stock choice being selected. No option is being offered to
divide the balance of the award between cash and XOMA common stock.

         The distribution date of awards under the Plan for each Plan Period
will be the same for all participants and is expected to be set no later than
ninety days after the end of each Plan Period.

         Questions concerning the Plan should be forwarded to the Vice President
of Human Resources. In all instances, the written provisions of the Plan and
other determinations of the Compensation Committee and the Board of Directors
shall govern and be final.

II.      Purposes.

         To build a corporate team that will achieve XOMA's goals and
objectives, to recognize individual efforts, to attract and retain highly
motivated individuals and to encourage outstanding performance and contributions
to XOMA.

III.     Definitions.

         For the purpose of this Plan, the following definitions will apply:

         A. Base Salaries. The term "Base Salaries" means total base salaries
         before any deferred tax reductions, excluding overtime, moving
         allowances, participation in clinical studies, incentive or bonus
         payments, shift differential, imputed income due to fringe benefits
         such as group insurance plans, and other

                                        2
<PAGE>
compensatory items of this type.

         B. Corporate Objectives. The term "Corporate Objectives" means that
         list of corporate objectives approved from time to time by the Board of
         Directors in its sole discretion for each Plan Period. The objectives
         may be based on financial goals, scientific or commercial progress,
         profits, return on investments or any other criteria established by the
         Board of Directors. The current Corporate Objectives, the milestones
         within each Corporate Objective and their respective relative
         percentage contribution to the overall Corporate Objectives and the
         Required Corporate Objective Percentage is set forth on Schedule I
         attached hereto together with an Explanatory Note describing the method
         of calculation.

         C. Employee. The term "Employee" means any individual on the XOMA
         payroll rendering services for XOMA whose normal work week is 30 hours
         or more (excluding consultants, advisors, and other similar individuals
         providing services to XOMA).

         D. Plan Period. Subject to Article VI, the term "Plan Period" means the
         fiscal period from July 1 to December 31, 1993 and, thereafter, each
         fiscal year ending December 31.

         E. Plan Term. Subject to Article VI, the term "Plan Term" means the
         period commencing on July 1, 1993 and continuing until the termination
         of this Plan by the Board of Directors.

IV.      Plan Mechanics.

         A. Eligibility. Officers, employees who have the title of Director or
         are in salary Grade E8 and above and report directly to an officer, and
         additional Discretionary Participants determined by the CEO to be
         critical to the achievement of the Corporate Objectives, are eligible
         for participation in the Plan. Other than the officers who may
         participate in the Plan who shall be designated in writing by the
         Compensation Committee, the CEO shall designate in writing the
         employees who will participate in the Plan. An individual who becomes
         an Employee who meets the eligibility criteria for participation in the
         Plan after the beginning of a Plan Period, or is promoted after the
         beginning of a Plan Period to a position eligible for participation in
         the Plan, will be considered by the Compensation Committee or the CEO,
         as the case may be, for participation in the Plan and, if designated in
         writing to participate, such Employee will have her/his award pro rated
         as of the date of eligibility determined by the Compensation Committee
         or the CEO, as the case may be. Because awards vest and are payable
         over a three-year term, each participant must maintain eligibility and
         continue as an Employee until each date of distribution to receive the
         distribution to be made on that date.

                                        3
<PAGE>
         B. Length of Plan. Subject to Article VI, the Plan will be effective
for the Plan Term.

         C.       Incentive Plan.

               1.   Determination of Amounts Available for Incentive
                    Compensation.

         a. Prior to the commencement of each Plan Period, the Compensation
         Committee acting on behalf of the Board of Directors in its sole
         discretion will determine the Target Incentive Compensation Pool. As
         soon as practicable after the end of each Plan Period, the Compensation
         Committee will determine whether and to what extent the Corporate
         Objectives have been met. If a determination is made that XOMA has not
         met the Corporate Objectives to the extent required, the Compensation
         Committee may decline to award any Incentive Compensation.

         b. The Board of Directors and the Compensation Committee have
         determined that, with respect to the years ending December 31, 1993 and
         1994, respectively, unless at least 50% and 60% of the Corporate
         Objectives (the "Required Minimum Corporate Objective Percentage") have
         been met, respectively, no Incentive Compensation will be awarded. In
         addition, with respect to the year ending December 31, 1995, and each
         year thereafter during the Plan Term, the Required Minimum Corporate
         Objective Percentage will increase to 70%.

         c. The Target Incentive Compensation Pool is expressed as a percentage
         of the aggregate annual Base Salaries of the participants in the Plan.
         The final Incentive Compensation Pool ("Final Incentive Compensation
         Pool") will be determined by utilizing the method of calculation of the
         extent to which XOMA's Corporate Objectives have been met as set forth
         in the Explanatory Note to Schedule I for the applicable Plan Period.

                  2.       Calculation of Individual Incentive Awards.

         a. It is the intention of the Compensation Committee and the Board of
         Directors that awards to participants shall vary depending on: (1) the
         extent of collective achievement of Corporate Objectives; (2) each
         participant's employment level in the organization and Base Salary; and
         (3) each participant's contributions to the achievement of the
         Corporate Objectives as a result of: (x) achievement of individual
         objectives and ongoing performance and (y) individual contributions
         towards XOMA's meeting of the Corporate Objectives without regard to
         individual objectives.

                                        4
<PAGE>
         b. Corporate and individual performance objectives will be weighted
         depending upon participant level. A 20% judgment factor will be
         included as an individual performance measurement for all participants
         in the Plan.

                  Corporate and individual performance goals for participants in
         the Plan are to be weighted as follows:

<TABLE>
<CAPTION>
                                                                                        Discretionary
         Participant                        Corporate             Individual            Performance
         Level                              Objectives            Objectives            Objectives
         <S>                                <C>                   <C>                   <C>
         Officer                            40%                   40%                   20%
         Other Executive                    30%                   50%                   20%
</TABLE>

         c. The bonus opportunity ranges for participants in the Plan expressed
         as a percentage of Base Salaries at the beginning of a Plan Period are
         as follows:

<TABLE>
<CAPTION>
         Participant Level                  Minimum               Target                Maximum
         <S>                                <C>                   <C>                   <C>
         Officer                            12.5%                 25%                   37.5%
         Other Executive                    7.5%                  15%                   27.5%
</TABLE>

         d. The performance of each participant in the Plan will be rated as
         soon as practicable following the conclusion of the applicable Plan
         Period in the exercise of the sole discretion of the individual or
         group indicated below. The ratings for all officers will be determined
         by the Compensation Committee. The ratings for all other participants
         will be determined by the CEO. Participants whose performance for the
         Plan Period is rated as unsatisfactory will not be eligible for
         participation in the Plan for that Plan Period and no Incentive
         Compensation will be awarded for below minimum performance.

         e. The total value of all awards made for the applicable Plan Period
         will not exceed the amount of the Final Incentive Compensation Pool
         determined for that Plan Period. Thus, each individual award for a
         participant from the Final Incentive Compensation Pool will vary
         depending on the participant's rating, employment level in the
         organization, Base Salary, and the individual ratings of all
         participants.

         3.       Awards to Participants.

          a. Approval. All awards will be approved following the end of a Plan
          Period by the Compensation Committee acting on the advice of the Board
          of Directors and the CEO.

          b. Distribution of Incentive Awards. The distribution dates for awards
          will be established by the Board of Directors acting on the advice of
          the Compensation Committee. Subject to vesting

                                        5
<PAGE>
         requirements, it is expected that distributions will normally be made
         in February or March of the succeeding year of the applicable Plan
         Period.

         c. Taxes and Withholding. Each participant will bear any Federal,
         state, and local taxes accruing with respect to any award under the
         Plan. As required by law, XOMA will withhold in cash from any
         distributions amounts required for Federal and state withholding tax
         purposes. With respect to awards in common stock, arrangements for the
         payment of withholding tax in cash satisfactory to XOMA must be made
         prior to the date of any distribution.

         d.       Termination of participation.

                  1. Subject to other provisions hereof, if a participant's
                  employment is terminated for any reason, or for no reason, on
                  or before December 31 of any Plan Period or at any time in any
                  subsequent year in which awards with respect to any Plan
                  Period are expected to be made, such participant shall forfeit
                  all rights to Incentive Compensation as yet unpaid pursuant to
                  the Plan.

                  2. If an Employee changes employment status from full-time to
                  part-time (less than 30 hours per week), any such change will
                  terminate participation in the Plan and all rights to payments
                  awarded for any Plan Period but payable in subsequent years,
                  unless the CEO determines in her/his sole discretion, that
                  such Employee should continue to participate.

                  3. A participant may elect to withdraw, without prejudice,
from the Plan at any time.

         e. Eligibility for Distribution. Subject to other provisions hereof, a
         participant must also be an Employee of the Company continuously from
         the conclusion of any Plan Period up to and including the date of
         distribution of the award to be eligible to receive such distribution.

         f. Change in Control Exception. Notwithstanding any other provision
         hereof, (x) if within one year after a "change in control" (as defined
         below), a participant's employment with XOMA is involuntarily
         terminated other than for cause, or (y) if a participant shall
         voluntarily terminate her or his employment with XOMA within one year
         after a change in control because the nature of such participant's
         duties or compensation do not continue to be substantially equivalent
         to what they were at the time of such change in control, then all
         awards authorized but not yet distributed to such participant shall be
         distributed to such participant.

                                        6
<PAGE>
         For the purposes of this subsection, a "change in control" shall have
         occurred if any person (as defined in Section 13 of the Securities
         Exchange Act of 1934, as amended) acquires shares of voting capital
         stock, (other than directly from XOMA) and thereby becomes the owner of
         more than 20% of XOMA's outstanding shares of voting capital stock (on
         a fully diluted basis) or XOMA enters into a merger or other
         consolidation (other than one in connection with a voluntary change of
         corporate domicile or similar reorganization or recapitalization
         transaction) in which the stockholders of XOMA (as determined
         immediately prior to the merger) do not own at least 50% of the
         outstanding shares of voting capital stock of the surviving entity
         after the merger. Solely for the purposes of the foregoing, a
         termination shall be deemed to have been made for "cause " in the event
         a participant is terminated for any of the following reasons:

               i)   the participant's continued failure to substantially perform
                    her or his duties with XOMA, or

               ii)  gross misconduct by the participant which is materially and
                    demonstrably injurious to XOMA or its employees.

         g. Death of a participant. In the event of the death of a participant
         while an Employee after the completion of any Plan Period but prior to
         the distribution, the award will be made as soon as practicable to the
         deceased participant's beneficiary as indicated on the participant's
         group insurance enrollment card.

V.       No Right to Employment.

         Nothing in this Plan shall give any participant the right to continued
employment by XOMA. Furthermore, under XOMA policy, employment at XOMA is "at
will" and can be terminated at any time by either party, with or without cause
and with or without notice.

VI.      Plan modification.

         This Plan may be modified or terminated by the Board of Directors at
any time.

VII.     Miscellaneous.

         A. Nontransferability. Awards shall not be transferable by a
participant except by will or the laws of descent and distribution and shall be
exercisable during the lifetime of a participant only by such participant or his
or her guardian or legal representative. A participant's rights under the Plan
may not be pledged, mortgaged, hypothecated, or otherwise encumbered, and shall
not be subject to claims of the participant's creditors.

         B.       Unfunded Status of Awards.  The Plan is intended to

                                        7
<PAGE>
constitute an "unfunded" plan of incentive compensation. With respect to any
payments not yet made to a participant pursuant to an award, nothing contained
in the Plan or any Award shall give any such participant any rights that are
greater than those of a general unsecured creditor of XOMA.

                                        8
<PAGE>
                                   Schedule I

                                Explanatory Note

         Each of the individual Corporate Objectives in this Schedule I has been
assigned a percentage reflecting its relative importance (the "Target
Contribution Percentage") to the achievement of the overall Corporate Objectives
as well as target results and results reflecting best and worst case scenarios
(denominated maximum or minimum for purposes of this Schedule I). If the target
results are achieved, the Target Contribution Percentage is awarded. If results
between the target and the best case scenario are achieved, the Target
Contribution Percentage is increased proportionately up to a maximum of 150% of
the Target Contribution Percentage (the "Best Case Percentage Limitation"). No
percentage contribution in excess of the Best Case Percentage Limitation will be
awarded. Alternatively, if target results are not met but results greater than
the worst case scenario are achieved, the Target Contribution Percentage will be
decreased proportionately to a minimum of 50% of the Target Contribution
Percentage. Achievements below the worst case scenario will result in a 0%
contribution from the applicable Corporate Objective.

                                        1




                            INDEMNIFICATION AGREEMENT

     THIS AGREEMENT, effective as of , is between XOMA CORPORATION, a Delaware
corporation ("Corporation"), and OFFICER ("Officer").

                                WITNESSETH THAT:

     WHEREAS, Officer is an executive officer of Corporation and performs a
valuable service in such capacity for Corporation; and

     WHEREAS, the stockholders of Corporation have adopted Bylaws (the "Bylaws")
providing for the indemnification of the officers, directors, agents and
employees of Corporation to the maximum extent authorized by Section 145 of the
Delaware Corporations Code, as amended ("Code"); and

     WHEREAS, such Bylaws and the Code, by their non-exclusive nature, permit
contracts between Corporation and its directors and officers with respect to
indemnification of such directors and officers; and

     WHEREAS, in accordance with the authorization as provided by the Code,
Corporation has purchased and presently maintains a policy or policies of
liability insurance for directors and officers ("D & O Insurance"), covering
certain liabilities which may be incurred by its directors and officers in the
performance as officers of Corporation; and

     WHEREAS, as a result of recent developments affecting the terms, scope and
availability of D & O Insurance there exists general uncertainty as to the
extent of protection afforded officers of Corporation by such D & O Insurance
and by statutory and by-law indemnification provisions; and

     WHEREAS, in order to induce Officer to continue to serve as an officer of
Corporation, Corporation has determined and agreed to enter into this contract
with Officer;

     NOW, THEREFORE, in consideration of Officer's continued service as an
officer after the date hereof, the parties hereto agree as follows:

     1. Indemnity of Officer. Subject to Section 5 hereof, Corporation hereby
agrees to hold harmless and indemnify Officer to the full extent authorized or
permitted by the provisions of the Code, as may be amended from time to time.

     2. Additional Indemnity. Subject to Section 5 hereof and to the exclusions
set forth in Section 3 hereof, Corporation hereby further agrees to hold
harmless and indemnify Officer:

                                       -1-
<PAGE>
     (a) against any and all expenses (including attorneys' fees), judgments,
fines and amounts paid in settlement actually and reasonably incurred by Officer
in connection with any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (including
an action by or in the right of Corporation) to which Officer is, was or at any
time becomes a party, or is threatened to be made a party, by reason of the fact
that Officer is or was an officer, director, employee or agent of Corporation,
or is or was serving at the request of Corporation as an officer, employee or
agent of another corporation, partnership, joint venture, trust or other
enterprise; and

     (b) otherwise to the fullest extent as may be provided to Officer by
Corporation under the non-exclusivity provisions of Article VII of Section 6 of
the Bylaws of Corporation and the Code.

     3. Limitations on Additional Indemnity. No indemnity pursuant to Section 2
hereof shall be paid by Corporation:

     (a) except to the extent the aggregate of losses to be indemnified
thereunder exceeds the amount of such losses for which Officer is indemnified
either pursuant to Section 1 hereof or pursuant to any other indemnification
arrangement or any D & O Insurance purchased and maintained by Corporation;

     (b) in respect to remuneration paid to Officer if it shall be determined by
a final judgment or other final adjudication that such remuneration was in
violation of law;

     (c) on account of any suit in which judgment is rendered against Officer
for an accounting of profits made from the purchase or sale by Officer of
securities of Corporation pursuant to the provisions of Section 16(b) of the
Securities Exchange Act of 1934 and amendments thereto or similar provisions of
any federal, state or local statutory law;

     (d) on account of Officer's conduct which is finally adjudged to have been
knowingly fraudulent or deliberately dishonest, or to constitute willful
misconduct; or

     (e) if a final decision by a court having jurisdiction in the matter shall
determine that such indemnification is not lawful.

     4. Contribution. If the indemnification provided in Sections 1 and 2 is
unavailable and may not be paid to Officer for any reason other than those set
forth in paragraphs (b), (c) and (d) of Section 3, then in respect of any
threatened, pending or completed action, suit or proceeding in which Corporation
is jointly liable with Officer (or would be if joined in such action, suit or
proceeding), Corporation shall contribute to the amount of expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred and paid

                                       -2-
<PAGE>
or payable by Officer in such proportion as is appropriate to reflect (i) the
relative benefits received by Corporation on the one hand and Officer on the
other hand from the transaction from which such action, suit or proceeding
arose, and (ii) the relative fault of Corporation on the one hand and of Officer
on the other in connection with the events which resulted in such expenses,
judgments, fines or settlement amounts, as well as any other relevant equitable
considerations. The relative fault of Corporation on the one hand and of Officer
on the other shall be determined by reference to, among other things, the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent the circumstances resulting in such expenses, judgments,
fines or settlement amounts. Corporation agrees that it would not be just and
equitable if contribution pursuant to this Section 4 were determined by pro rata
allocation or any other method of allocation which does not take account of the
foregoing equitable considerations.

     5. Continuation of Obligations. All agreements and obligations of
Corporation contained herein shall terminate on the third anniversary of the
date hereof (the "Termination Date"); provided, however, that such agreements
and obligations shall continue thereafter with respect to any claim or
threatened, pending or completed action, suit or proceeding, whether civil,
criminal or investigative, to which Officer is or becomes subject on or
subsequent to the Termination Date by reason of the fact that Officer was an
officer of Corporation or serving in any other capacity referred to herein on or
prior to the Termination Date.

     6. Notification and Defense of Claim. Promptly after receipt by Officer of
notice of the commencement of any action, suit or proceeding, Officer will, if a
claim in respect thereof is to be made against Corporation under this Agreement,
notify Corporation of the commencement thereof; but the omission so to notify
Corporation will not relieve it from any liability which it may have to Officer
otherwise than under this Agreement. With respect to any such action, suit or
proceeding as to which Officer notifies Corporation of the commencement thereof:

     (a) Corporation will be entitled to participate therein at its own expense;

     (b) except as otherwise provided below, to the extent that it may wish,
Corporation jointly with any other indemnifying party similarly notified will be
entitled to assume the defense thereof, with counsel satisfactory to Officer.
After notice from Corporation to Officer of its election so as to assume the
defense thereof, Corporation will not be liable to Officer under this Agreement
for any legal or other expenses subsequently incurred by Officer in connection
with the defense thereof other than reasonable costs of investigation or as
otherwise provided below. Officer shall have the right to employ counsel to
represent Officer in such action, suit or proceeding but the fees and expenses
of

                                       -3-
<PAGE>
such counsel incurred after notice from Corporation of its assumption of the
defense thereof shall be at the expense of Officer unless such counsel is
reasonably satisfactory to Corporation and (i) Officer shall have reasonably
concluded that there may be a conflict of interest between Corporation and
Officer in the conduct of the defense of such action, or (ii) Corporation shall
not in fact have employed counsel to assume the defense of such action, in each
of which cases the fees and expenses of counsel shall be at the expense of
Corporation. Corporation shall not be entitled to assume the defense of any
action, suit or proceeding brought by or on behalf of Corporation or as to which
Officer shall have made the conclusion provided for in (ii) above. Officer also
shall have the right to employ counsel reasonably satisfactory to Corporation to
represent Officer in any such action, suit or proceeding with respect to which
Corporation does not assume the defense; and

     (c) Corporation shall not be liable to indemnify Officer under this
Agreement for any amounts paid in settlement of any action or claim effected
without its written consent. Corporation shall not settle any action or claim in
any manner which would impose any penalty or limitation on Officer without
Officer's written consent. Neither Corporation nor Officer will unreasonably
withhold its consent to any proposed settlement.

     7. Advancement and Repayment of Expenses.

     (a) In the event that Officer employs Officer's own counsel pursuant to
Section 6(b) above, Corporation shall advance to Officer, prior to any final
disposition of any threatened or pending action, suit or proceeding, whether
civil, criminal, administrative or investigative, any and all reasonable
expenses (including legal fees and expenses) incurred in investigating or
defending any such action, suit or proceeding within ten (10) days after
receiving copies of invoices presented to Officer for such expenses.

     (b) Officer agrees that Officer will reimburse Corporation for all
reasonable expenses paid by Corporation in defending any civil or criminal
action, suit or proceeding against Officer in the event and only to the extent
it shall be ultimately determined pursuant to the procedure specified in Section
145(d) of the Code that Officer is not entitled, under the provisions of the
Code, the Bylaws, this Agreement or otherwise, to be indemnified by Corporation
for such expenses.

     8. Enforcement.

     (a) Corporation expressly confirms and agrees that it has entered into this
Agreement and assumed the obligations imposed on Corporation hereby in order to
induce Officer to continue as an officer of Corporation, and acknowledges that
Officer is relying upon this Agreement in continuing such capacity.

                                       -4-
<PAGE>
     (b) In the event Officer is required to bring any action to enforce rights
or to collect moneys due under this Agreement and is successful in such action,
Corporation shall reimburse Officer for all of Officer's reasonable fees and
expenses in bringing and pursuing such action.

     9. Separability. Each of the provisions of this Agreement is a separate and
distinct agreement and independent of the others, so that if any provision
hereof shall be held to be valid or unenforceable for any reason, such
invalidity or unenforceability shall not affect the validity or enforceability
of the other provisions hereof.

     10. Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Delaware.

     11. Binding Effect. This Agreement shall be binding upon Officer and upon
Corporation, its successors and assigns, and shall inure to the benefit of
Officer, his heirs, personal representatives and assigns, to the benefit of
Corporation, its successors and assigns.

                                       -5-
<PAGE>
     12. Amendment and Termination. No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement this
day of and it shall be effective as of the day and year first above written.

                                    XOMA CORPORATION

                                    By:
                                       ------------------------------
                                         John L. Castello
                                         Chairman of the Board,
                                         President and
                                         Chief Executive Officer

                                    OFFICER

                                    Title:   Title

                                       -6-





                            INDEMNIFICATION AGREEMENT

     THIS AGREEMENT, effective as of is between XOMA CORPORATION, a Delaware
corporation ("Corporation"), and ("Officer").

                                WITNESSETH THAT:

     WHEREAS, Officer is a director and an executive officer of Corporation and
performs a valuable service in such capacity for Corporation; and

     WHEREAS, the stockholders of Corporation have adopted Bylaws (the "Bylaws")
providing for the indemnification of the officers, directors, agents and
employees of Corporation to the maximum extent authorized by Section 145 of the
Delaware Corporations Code, as amended ("Code"); and

     WHEREAS, such Bylaws and the Code, by their non-exclusive nature, permit
contracts between Corporation and its directors and officers with respect to
indemnification of such directors and officers; and

     WHEREAS, in accordance with the authorization as provided by the Code,
Corporation has purchased and presently maintains a policy or policies of
liability insurance for directors and officers ("D & O Insurance"), covering
certain liabilities which may be incurred by its directors and officers in the
performance of their duties as directors and officers of Corporation; and

     WHEREAS, as a result of recent developments affecting the terms, scope and
availability of D & O Insurance there exists general uncertainty as to the
extent of protection afforded directors and officers of Corporation by such D &
O Insurance and by statutory and by-law indemnification provisions; and

     WHEREAS, in order to induce Officer to continue to serve as a director and
an executive officer of Corporation, Corporation has determined and agreed to
enter into this contract with Officer;

     NOW, THEREFORE, in consideration of Officer's continued service as a
director and an executive officer after the date hereof, the parties hereto
agree as follows:

     1. Indemnity of Officer. Subject to Section 5 hereof, Corporation hereby
agrees to hold harmless and indemnify Officer to the fullest extent authorized
or permitted by the provisions of the Code, as may be amended from time to time.

     2. Additional Indemnity. Subject to Section 5 hereof and to the exclusions
set forth in Section 3 hereof, Corporation hereby further agrees to hold
harmless and indemnify Officer:

                                       -1-
<PAGE>
     (a) against any and all expenses (including attorneys' fees), judgments,
fines and amounts paid in settlement actually and reasonably incurred by Officer
in connection with any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (including
an action by or in the right of Corporation) to which Officer is, was or at any
time becomes a party, or is threatened to be made a party, by reason of the fact
that Officer is or was an officer, director, employee or agent of Corporation,
or is or was serving at the request of Corporation as an officer, director,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise; and

     (b) otherwise to the fullest extent as may be provided to Officer by
Corporation under the non-exclusivity provisions of Article VII of Section 6 of
the Bylaws of Corporation and the Code.

     3. Limitations on Additional Indemnity. No indemnity pursuant to Section 2
hereof shall be paid by Corporation:

     (a) except to the extent the aggregate of losses to be indemnified
thereunder exceeds the amount of such losses for which Officer is indemnified
either pursuant to Section 1 hereof or pursuant to any other indemnification
arrangement or any D & O Insurance purchased and maintained by Corporation;

     (b) in respect to remuneration paid to Officer if it shall be determined by
a final judgment or other final adjudication that such remuneration was in
violation of law;

     (c) on account of any suit in which judgment is rendered against Officer
for an accounting of profits made from the purchase or sale by Officer of
securities of Corporation pursuant to the provisions of Section 16(b) of the
Securities Exchange Act of 1934 and amendments thereto or similar provisions of
any federal, state or local statutory law;

     (d) on account of Officer's conduct which is finally adjudged to have been
knowingly fraudulent or deliberately dishonest, or to constitute willful
misconduct; or

     (e) if a final decision by a court having jurisdiction in the matter shall
determine that such indemnification is not lawful.

     4. Contribution. If the indemnification provided in Sections 1 and 2 is
unavailable and may not be paid to Officer for any reason other than those set
forth in paragraphs (b), (c) and (d) of Section 3, then in respect of any
threatened, pending or completed action, suit or proceeding in which Corporation
is jointly liable with Officer (or would be if joined in such action, suit or
proceeding), Corporation shall contribute to the amount of expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred and paid or payable by Officer in such proportion as is
appropriate to reflect (i) the relative benefits received by Corporation on the
one hand

                                       -2-
<PAGE>
and Officer on the other hand from the transaction from which such action, suit
or proceeding arose, and (ii) the relative fault of Corporation on the one hand
and of Officer on the other in connection with the events which resulted in such
expenses, judgments, fines or settlement amounts, as well as any other relevant
equitable considerations. The relative fault of Corporation on the one hand and
of Officer on the other shall be determined by reference to, among other things,
the parties' relative intent, knowledge, access to information and opportunity
to correct or prevent the circumstances resulting in such expenses, judgments,
fines or settlement amounts. Corporation agrees that it would not be just and
equitable if contribution pursuant to this Section 4 were determined by pro rata
allocation or any other method of allocation which does not take account of the
foregoing equitable considerations.

     5. Continuation of Obligations. All agreements and obligations of
Corporation contained herein shall terminate on the date that Officer ceases to
be either a director or an officer of the Corporation (the "Termination Date");
provided, however, that such agreements and obligations shall continue
thereafter with respect to any claim or threatened, pending or completed action,
suit or proceeding, whether civil, criminal or investigative, to which Officer
is or becomes subject on or subsequent to the Termination Date by reason of the
fact that Officer was a director and/or an officer of Corporation or serving in
any other capacity referred to herein on or prior to the Termination Date.

     6. Notification and Defense of Claim. Promptly after receipt by Officer of
notice of the commencement of any action, suit or proceeding, Officer will, if a
claim in respect thereof is to be made against Corporation under this Agreement,
notify Corporation of the commencement thereof; but the omission so to notify
Corporation will not relieve it from any liability which it may have to Officer
otherwise than under this Agreement. With respect to any such action, suit or
proceeding as to which Officer notifies Corporation of the commencement thereof:

     (a) Corporation will be entitled to participate therein at its own expense;

     (b) except as otherwise provided below, to the extent that it may wish,
Corporation jointly with any other indemnifying party similarly notified will be
entitled to assume the defense thereof, with counsel reasonably satisfactory to
Officer. After notice from Corporation to Officer of its election to assume the
defense thereof, Corporation will not be liable to Officer under this Agreement
for any legal or other expenses subsequently incurred by Officer in connection
with the defense thereof other than reasonable costs of investigation or as
otherwise provided below. Officer shall have the right to employ counsel in such
action, suit or proceeding, but the fees and expenses of such counsel incurred
after notice from Corporation of its assumption of the defense thereof shall be
at the expense of Officer unless such counsel is reasonably satisfactory to
Corporation and (i) Officer shall have reasonably concluded that there may be a
conflict of

                                       -3-
<PAGE>
interest between Corporation and Officer in the conduct of the defense of such
action, or (ii) Corporation shall not in fact have employed counsel to assume
the defense of Officer in such action, in each of which cases the fees and
expenses of counsel shall be at the expense of Corporation. Corporation shall
not be entitled to assume the defense of any action, suit or proceeding brought
by or on behalf of Corporation or as to which Officer shall have made the
conclusion provided for in (i) above. Officer also shall have the right to
employ counsel reasonably satisfactory to Corporation to represent Officer in
any such action, suit or proceeding with respect to which Corporation does not
assume the defense; and

     (c) Corporation shall not be liable to indemnify Officer under this
Agreement for any amounts paid in settlement of any action or claim effected
without its written consent. Corporation shall not settle any action or claim in
any manner which would impose any penalty or limitation on Officer without
Officer's written consent. Neither Corporation nor Officer will unreasonably
withhold its consent to any proposed settlement.

     7. Advancement and Repayment of Expenses.

     (a) In the event that Officer employs Officer's own counsel pursuant to
Section 6(b) above, Corporation shall advance to Officer, prior to any final
disposition of any threatened or pending action, suit or proceeding, whether
civil, criminal, administrative or investigative, any and all reasonable
expenses (including legal fees and expenses) incurred in investigating or
defending any such action, suit or proceeding within ten (10) days after
receiving copies of invoices presented to Officer for such expenses.

     (b) Officer agrees that Officer will reimburse Corporation for all
reasonable expenses paid by Corporation in defending any civil or criminal
action, suit or proceeding against Officer in the event and only to the extent
it shall be ultimately determined pursuant to the procedure specified in Section
145(d) of the Code that Officer is not entitled, under the provisions of the
Code, the Bylaws, this Agreement or otherwise, to be indemnified by Corporation
for such expenses.

     8. Enforcement.

     (a) Corporation expressly confirms and agrees that it has entered into this
Agreement and assumed the obligations imposed on Corporation hereby in order to
induce Officer to continue as a director and an officer of Corporation, and
acknowledges that Officer is relying upon this Agreement in continuing in such
capacity.

     (b) In the event Officer is required to bring any action to enforce rights
or to collect moneys due under this Agreement and is successful in such action,
Corporation shall reimburse Officer for all of Officer's reasonable fees and
expenses in bringing and pursuing such action.

                                       -4-
<PAGE>
     9. Separability. Each of the provisions of this Agreement is a separate and
distinct agreement and independent of the others, so that if any provision
hereof shall be held to be invalid or unenforceable for any reason, such
invalidity or unenforceability shall not affect the validity or enforceability
of the other provisions hereof.

     10. Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Delaware.

     11. Binding Effect. This Agreement shall be binding upon Officer and upon
Corporation, its successors and assigns, and shall inure to the benefit of
Officer, his heirs, personal representatives and assigns, and to the benefit of
Corporation, its successors and assigns.

     12. Amendment and Termination. No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement this
day of , and it shall be effective as of the day and year first above written.

                                  XOMA CORPORATION

                                  By:
                                  ------------------------------------
                                  Employee Director Signature

                                       -5-



                            INDEMNIFICATION AGREEMENT

     THIS AGREEMENT, effective as of is between XOMA CORPORATION, a Delaware
corporation ("Corporation"), and ("Director").

                                WITNESSETH THAT:

     WHEREAS, Director is a director of Corporation and performs a valuable
service in such capacity for Corporation; and

     WHEREAS, the stockholders of Corporation have adopted Bylaws (the "Bylaws")
providing for the indemnification of the officers, directors, agents and
employees of Corporation to the maximum extent authorized by Section 145 of the
Delaware Corporations Code, as amended ("Code"); and

     WHEREAS, such Bylaws and the Code, by their non-exclusive nature, permit
contracts between Corporation and its directors and officers with respect to
indemnification of such directors and officers; and

     WHEREAS, in accordance with the authorization as provided by the Code,
Corporation has purchased and presently maintains a policy or policies of
liability insurance for directors and officers ("D & O Insurance"), covering
certain liabilities which may be incurred by its directors and officers in the
performance of their duties as directors and officers of Corporation; and

     WHEREAS, as a result of recent developments affecting the terms, scope and
availability of D & O Insurance there exists general uncertainty as to the
extent of protection afforded directors and officers of Corporation by such D &
O Insurance and by statutory and by-law indemnification provisions; and

     WHEREAS, in order to induce Director to continue to serve as a director of
Corporation, Corporation has determined and agreed to enter into this contract
with Director;

     NOW, THEREFORE, in consideration of Director's continued service as a
director after the date hereof, the parties hereto agree as follows:

     1. Indemnity of Director. Subject to Section 5 hereof, Corporation hereby
agrees to hold harmless and indemnify Director to the fullest extent authorized
or permitted by the provisions of the Code, as may be amended from time to time.

     2. Additional Indemnity. Subject to Section 5 hereof and to the exclusions
set forth in Section 3 hereof, Corporation hereby further agrees to hold
harmless and indemnify Director:

                                       -1-
<PAGE>
     (a) against any and all expenses (including attorneys' fees), judgments,
fines and amounts paid in settlement actually and reasonably incurred by
Director in connection with any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (including
an action by or in the right of Corporation) to which Director is, was or at any
time becomes a party, or is threatened to be made a party, by reason of the fact
that Director is or was an officer, director, employee or agent of Corporation,
or is or was serving at the request of Corporation as an officer, director,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise; and

     (b) otherwise to the fullest extent as may be provided to Director by
Corporation under the non-exclusivity provisions of Article VII of Section 6 of
the Bylaws of Corporation and the Code.

     3. Limitations on Additional Indemnity. No indemnity pursuant to Section 2
hereof shall be paid by Corporation:

     (a) except to the extent the aggregate of losses to be indemnified
thereunder exceeds the amount of such losses for which Director is indemnified
either pursuant to Section 1 hereof or pursuant to any other indemnification
arrangement or any D & O Insurance purchased and maintained by Corporation;

     (b) in respect to remuneration paid to Director if it shall be determined
by a final judgment or other final adjudication that such remuneration was in
violation of law;

     (c) on account of any suit in which judgment is rendered against Director
for an accounting of profits made from the purchase or sale by Director of
securities of Corporation pursuant to the provisions of Section 16(b) of the
Securities Exchange Act of 1934 and amendments thereto or similar provisions of
any federal, state or local statutory law;

     (d) on account of Director's conduct which is finally adjudged to have been
knowingly fraudulent or deliberately dishonest, or to constitute willful
misconduct; or

     (e) if a final decision by a court having jurisdiction in the matter shall
determine that such indemnification is not lawful.

     4. Contribution. If the indemnification provided in Sections 1 and 2 is
unavailable and may not be paid to Director for any reason other than those set
forth in paragraphs (b), (c) and (d) of Section 3, then in respect of any
threatened, pending or completed action, suit or proceeding in which Corporation
is jointly liable with Director (or would be if joined in such action, suit or
proceeding), Corporation shall contribute to the amount of expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred and paid or -2-
<PAGE>
payable by Director in such proportion as is appropriate to reflect (i) the
relative benefits received by Corporation on the one hand and Director on the
other hand from the transaction from which such action, suit or proceeding
arose, and (ii) the relative fault of Corporation on the one hand and of
Director on the other in connection with the events which resulted in such
expenses, judgments, fines or settlement amounts, as well as any other relevant
equitable considerations. The relative fault of Corporation on the one hand and
of Director on the other shall be determined by reference to, among other
things, the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent the circumstances resulting in such expenses,
judgments, fines or settlement amounts. Corporation agrees that it would not be
just and equitable if contribution pursuant to this Section 4 were determined by
pro rata allocation or any other method of allocation which does not take
account of the foregoing equitable considerations.

     5. Continuation of Obligations. All agreements and obligations of
Corporation contained herein shall terminate on the date that Director ceases to
be a director of the Corporation (the "Termination Date"); provided, however,
that such agreements and obligations shall continue thereafter with respect to
any claim or threatened, pending or completed action, suit or proceeding,
whether civil, criminal or investigative, to which Director is or becomes
subject on or subsequent to the Termination Date by reason of the fact that
Director was a director of Corporation or serving in any other capacity referred
to herein on or prior to the Termination Date.

     6. Notification and Defense of Claim. Promptly after receipt by Director of
notice of the commencement of any action, suit or proceeding, Director will, if
a claim in respect thereof is to be made against Corporation under this
Agreement, notify Corporation of the commencement thereof; but the omission so
to notify Corporation will not relieve it from any liability which it may have
to Director otherwise than under this Agreement. With respect to any such
action, suit or proceeding as to which Director notifies Corporation of the
commencement thereof:

     (a) Corporation will be entitled to participate therein at its own expense;

     (b) except as otherwise provided below, to the extent that it may wish,
Corporation jointly with any other indemnifying party similarly notified will be
entitled to assume the defense thereof, with counsel reasonably satisfactory to
Director. After notice from Corporation to Director of its election to assume
the defense thereof, Corporation will not be liable to Director under this
Agreement for any legal or other expenses subsequently incurred by Director in
connection with the defense thereof other than reasonable costs of investigation
or as otherwise provided below. Director shall have the right to employ counsel
to represent Director in such action, suit or proceeding, but the fees 

                                      -3-


<PAGE>
and expenses of such counsel incurred after notice from Corporation of its
assumption of the defense thereof shall be at the expense of Director unless
such counsel is reasonably satisfactory to Corporation and (i) Director shall
have reasonably concluded that there may be a conflict of interest between
Corporation and Director in the conduct of the defense of such action, or (ii)
Corporation shall not in fact have employed counsel to assume the defense of
Director in such action, in each of which cases the fees and expenses of counsel
shall be at the expense of Corporation. Corporation shall not be entitled to
assume the defense of any such action, suit or proceeding brought by or on
behalf of Corporation or as to which Director shall have made the conclusion
provided for in (ii) above. Director also shall have the right to employ counsel
reasonably satisfactory to Corporation to represent Director in any such action,
suit or proceeding with respect to which Corporation does not assume the
defense; and

     (c) Corporation shall not be liable to indemnify Director under this
Agreement for any amounts paid in settlement of any action or claim effected
without its written consent. Corporation shall not settle any action or claim in
any manner which would impose any penalty or limitation on Director without
Director's written consent. Neither Corporation nor Director will unreasonably
withhold its consent to any proposed settlement.

     7. Advancement and Repayment of Expenses.

     (a) In the event that Director employs Director's own counsel pursuant to
Section 6(b) above, Corporation shall advance to Director, prior to any final
disposition of any threatened or pending action, suit or proceeding, whether
civil, criminal, administrative or investigative, any and all reasonable
expenses (including legal fees and expenses) incurred in investigating or
defending any such action, suit or proceeding within ten (10) days after
receiving copies of invoices presented to Director for such expenses.

     (b) Director agrees that Director will reimburse Corporation for all
reasonable expenses paid by Corporation in defending any civil or criminal
action, suit or proceeding against Director in the event and only to the extent
it shall be ultimately determined pursuant to the procedure specified in Section
145(d) of the Code that Director is not entitled, under the provisions of the
Code, the Bylaws, this Agreement or otherwise, to be indemnified by Corporation
for such expenses.

     8. Enforcement.

     (a) Corporation expressly confirms and agrees that it has entered into this
Agreement and assumed the obligations imposed on Corporation hereby in order to
induce Director to continue as a director of Corporation, and acknowledges that
Director is relying upon this Agreement in continuing in such capacity.

                                       -4-
<PAGE>
     (b) In the event Director is required to bring any action to enforce rights
or to collect moneys due under this Agreement and is successful in such action,
Corporation shall reimburse Director for all of Director's reasonable fees and
expenses in bringing and pursuing such action.

     9. Separability. Each of the provisions of this Agreement is a separate and
distinct agreement and independent of the others, so that if any provision
hereof shall be held to be invalid or unenforceable for any reason, such
invalidity or unenforceability shall not affect the validity or enforceability
of the other provisions hereof.

     10. Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Delaware.

     11. Binding Effect. This Agreement shall be binding upon Director and upon
Corporation, its successors and assigns, and shall inure to the benefit of
Director, his heirs, personal representatives and assigns, and to the benefit of
Corporation, its successors and assigns.

                                       -5-
<PAGE>
     12. Amendment and Termination. No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement this
day of , and it shall be effective as of the day and year first above written.

                                       XOMA CORPORATION

                                       By

                                       Non-Employee Director Signature

                                       -6-




                                XOMA CORPORATION

                              EMPLOYMENT AGREEMENT
                                      with
                                JOHN L. CASTELLO

                                                            Berkeley, California

THIS AGREEMENT is made as of the 29th day of April, 1992 by and between XOMA
CORPORATION, a Delaware Corporation (the "Corporation"), and John L. Castello,
employee ("Employee").

     1. Employment. On the terms and conditions set forth herein, Corporation
hereby employs Employee, and Employee hereby accepts such employment. While
employed hereunder, Employee shall devote all of the Employee's best efforts and
attention to the business and affairs of the Corporation; however, Employee may
continue to be a member of the Board of Directors of Alpha Therapeutics
Corporation, IBA, PMA, and serve on other such boards as Employee and the
Corporation may jointly agree, as well as Employee may continue to act under his
Consultancy Agreement of August 1, 1991 with Ares-Serono, Inc.

     2. Compensation. (i) Employee's rate of compensation shall be as set forth
on Exhibit I attached hereto and incorporated herein and shall be payable in
equal, semi-monthly installments on the fifteenth and the last day of each month
unless otherwise agreed by the parties; (ii) Employee shall be reimbursed for
reasonable out-of-pocket expenses incurred by Employee in performing services
for the Corporation upon such terms and conditions as may be established from
time to time by the Corporation.

     3. Proprietary Rights. Prior to, or coincidental with, the execution of
this Agreement, Employee has or will execute and deliver to the Corporation an
agreement in form and substance as set forth in Exhibit II attached hereto and
incorporated herein.

     4. Conflicts and Non-Competition. Notwithstanding any provisions of the
Agreement, including specifically those set forth in paragraphs 1 and 3
hereinabove, while employed hereunder by Corporation, Employee will not,
directly or indirectly, engage in any other activity involving a conflict of
interest between Employee or any third party and Corporation or in any other
occupation, employment, consultation or other activity in competition with the
business, developments, products, work or activities of the Corporation.

     5. Other Provisions. Any Additional Provisions relating to Employee's
employment hereunder are set forth in Exhibit I hereto.


<PAGE>


XOMA CORPORATION
EMPLOYMENT AGREEMENT

     6. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California.

     7. Counterparts. This Agreement may be executed in counterparts, each of
which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument.

     8. Successors and Assigns. Except as otherwise expressly provided in this
Agreement, the provisions hereof shall inure to the benefit of the successors
and assigns of the Corporation. Employee shall not assign any rights or delegate
any obligations hereunder without the prior written consent of Corporation. The
Corporation may transfer its rights hereunder to any other person or entity.

     9. Termination of At-Will Employment. It is understood that Employee's
employment is not for a specified term and that it may be terminated, with or
without cause, and with or without notice, at any time at the will of either
Employee or the CORPORATION irrespective of any statements to the contrary
appearing anywhere in the CORPORATION's publications. It is also understood that
no agreement contrary to the foregoing has been made by or between the
Corporation and Employee.

     10. Entire Agreement. The terms of this Agreement, together with those set
forth in Exhibit I hereto and Appendix A thereto, are intended by the parties to
be the final expression of their agreement with respect to the employment of
Employee by the Corporation and may not be contradicted by evidence of any prior
or contemporaneous agreement. The parties further intend that this Agreement
shall constitute the complete and exclusive statement of its terms and that no
extrinsic evidence whatsoever may be introduced in any judicial, administrative,
or other legal proceeding involving this Agreement.

     11. Amendments; Waivers. This Agreement may not be modified, amended, or
terminated except by an instrument in writing, signed by the Employee and by a
duly authorized representative of the Corporation other than Employee. By an
instrument in writing similarly executed, either party may waive compliance by
the other party with any provision of this Agreement that such other party was
or is obligated to comply with or perform, provided, however, that such waiver
shall not operate as a waiver of, or estoppel with respect to, any other or
subsequent failure. No failure to exercise and no delay in exercising any right,
remedy, or power hereunder shall operate as a waiver thereof, nor shall any
single or partial exercise of any right,

                                       -2-


<PAGE>


XOMA CORPORATION
EMPLOYMENT AGREEMENT

remedy, or power hereunder preclude any other or further exercise thereof or the
exercise of any other right, remedy, or power provided herein or by law or in
equity.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
and year first written above.

XOMA CORPORATION                            EMPLOYEE

By: /s/Steven C. Mendell                    /s/John L. Castello
Steven C. Mendell                           John L. Castello
Title: Chairman of the Board

                                       -3-


<PAGE>


                                XOMA CORPORATION

                  EMPLOYMENT AGREEMENT - ADDITIONAL PROVISIONS

                                    EXHIBIT I

                           EMPLOYEE: JOHN L. CASTELLO

1.   Rate of Compensation:

     The salary of Employee will be $500,000 per year and will be paid to
Employee in equal payments semi-monthly on the 15th and last day of each month.
All performance reviews of Employee will be by the Board of Directors of the
Company.

2.   Employee Benefits:

     Employee will be entitled to all XOMA employee benefits, which shall
include:

     (a) Xoma's standard insurance benefits;

     (b) In addition to the foregoing:

               i. Life Insurance. Xoma will provide Employee with supplemental
          life insurance for the amount that an annual premium of $18,000
          provides.

               ii. Tax and Financial Planning. Xoma will provide to Employee
          annually for the Employee's retention of attorneys, accountants and/or
          financial consultants of Employee's own choosing for the Employee's
          personal tax and financial planning, at an annual cost to Xoma not to
          exceed $7,000.

3.   Relocation:

     It will be necessary for Employee to relocate to the greater Berkeley,
California area, and the Corporation will provide reimbursement for all
necessary and reasonable costs including but not limited to the actual cost of
the movement of Employee's goods, packing, insuring and so forth; real estate
brokers and related fees; and costs of Employee for acquiring a mortgage on a
new principal residence. All of these costs will be grossed up for federal and
state income tax purposes. For this purpose, "grossed up" means that in the case
of a reimbursed expense that is taxable to Employee and is not deductible for
one or both of federal and state income tax purposes, Employee will be paid an
amount which, after taxes on such amount, will equal the amount of the
non-deductible reimbursable expenses. Appropriate temporary housing, if
required, will be provided to Employee at no additional out-of-

                                       -4-
<PAGE>
pocket expense for a period of up to six (6) months after commencement of
employment. The relocation benefits shall be in effect for a period of one year
after the commencement of employment.

4.   Vacation:

     Employee will be granted an annual vacation in the amount of four (4)
weeks, with full pay commencing for the first year of employment; that is,
Employee shall be entitled to take four (4) weeks vacation during the first year
of employment.

5.   Stock Option:

     As an inducement to Employee to enter into the employment of the
Corporation, an option has been granted to Employee in accordance with the
now-in-force option plan in the amount of 500,000 shares of the common stock of
the Corporation. Such option shall be in accordance with such option plan, and
shall be in accordance with the currently existing form of Stock Option
Agreement under the Xoma Corporation 1981 Stock Option Plan, as amended, a copy
of which is attached hereto as Appendix A.

6.   Additional Capacities, President and Chief Executive Officer:

     Employee is required to assume the responsibilities of President and Chief
Executive Officer and member of the Board of Directors of the Corporation with
all the rights and privileges typically associated with this type of role. As
the President and Chief Executive Officer, Employee will report to the Board of
Directors of the Corporation. As such President and Chief Executive Officer,
Employee will be responsible for conducting the day-to-day affairs of the
Corporation, interpreting and applying the policies and direction of the Board
of Directors, making and applying supplemental applications and guidelines,
building and controlling the operations of the Corporation, executing the
corporate strategy, and practicing diligent management. Commensurate with the
by-laws of the Corporation and policies of the Board of Directors, Employee will
have sufficient authority to accomplish all of the above-mentioned
responsibilities.

     Employee shall use his best efforts in directing the business of the
Corporation with the objective of providing maximum profit and return on
invested capital and assuring the development, manufacture and marketing of only
safe and efficacious products; establishing current and long-range objectives,
plans and policies subject to the approval of the Board of Directors; and
representing the Corporation with its major governmental authorities that have
any control over the Corporation or its products, its major customers, the
financial community and the public.

                                       -5-
<PAGE>
7.   Business Expense Reimbursement, and Perquisites:

     During the term of his employment hereunder, Employee shall be entitled to
receive proper reimbursement for all reasonable out-of-pocket expenses incurred
by him (in accordance with the policies and procedures established by the
Corporation for its senior executive officers) in performing services hereunder,
provided Employee properly accounts therefor. Employee shall have the privilege
at his option to fly commercially on a class of service chosen by Employee.

     Employee will be required at Corporation expense to take an annual physical
examination by a physician of his own choice acceptable to the Corporation, and
a report of any material health problems shall be rendered to the Board.

8.   Early Termination Obligation of the Corporation:

     While this Employment Agreement provides for termination of at-will
employment of the Employee, as part of the inducement and offer to Employee to
enter into employment with the Corporation, should the Corporation terminate the
services of Employee as an Employee of the Corporation for any reason other than
for "Due Cause" (as that term is defined hereinbelow), the Corporation shall pay
Employee's base level salary in effect at the time of any such termination for
one year thereafter. Such termination other than for Due Cause shall include
termination by the Employee for "Good Reason" (as that therm is defined
hereinbelow), in which event the Corporation shall be obligated to pay such
one-year salary.

9.   Consequence of Termination of Employment:

     9.1 Death. In the event of the death of the Employee during the term of
this Agreement, his salary shall cease at the end of the month in which death
occurs and all unpaid amounts, shall be paid to the Employee's designated
beneficiary, or in the absence of such designation to the estate or other legal
representative of the Employee at the time of death. Other death benefits will
be determined in accordance with the terms of the Corporation's benefit programs
and plans.

     9.2 Disability. In the event of the Employee's permanent disability, the
Employee shall be entitled to his salary for a period of one (1) year after such
disability commences and other benefits as determined in accordance with the
terms of the Corporation's benefit programs and plans.

     Notwithstanding anything in this Agreement to the contrary, the Corporation
is hereby given the option to terminate the Employee's employment in the event
that the Employee shall, during the term hereof, become permanently disabled as
the term permanently disabled is hereinafter defined. Such option shall be

                                       -6-
<PAGE>
exercised by the Corporation giving notice to Employee by certified mail of the
Corporation's intention to terminate his employment due to permanent disability
on the last day of the month during which such notice is mailed.

     For purposes of this Agreement, Employee shall be deemed to have become
permanently disabled, if, during the term hereof, because of physical or mental
disability he becomes unable or shall have been unable to perform his duties
hereunder (a) for 120 consecutive days, or (b) for 180 days (irrespective of
whether such days are consecutive) occurring during any period of 365
consecutive days.

     During a period in which the one-year salary payments are being made
pursuant to the first paragraph of this Section 9.2, the Employee will undergo
reasonable periodic medical examinations to confirm the continuation of his
disability. Such medical examinations will be conducted by a medical doctor
chosen by the parties. If the parties cannot agree on such a doctor, they each
shall select a medical doctor and the two doctors shall select a third medical
doctor for this purpose. In the event that the Corporation has terminated
Employee because of permanent disability notwithstanding a determination by a
medical doctor, chosen as described in the preceding sentence, that Employee is
no longer subject to a permanent disability as defined in this Section 9.2,
Employee will continue to be entitled to receive the one-year salary payments as
herein set forth, provided that, following such determination, he makes a
continuing reasonable effort to find employment at such time commensurate with
his abilities, experience, and background.

     9.3 Termination by the Corporation for Due Cause. Nothing herein shall
prevent the Corporation from terminating Employee's employment for Due Cause.
Employee shall continue to receive salary for the period ending with the date of
such termination as provided in this Section 9.3. Any rights and benefits he may
have in respect of any other compensation or employee benefit plans or programs
of the Corporation shall be determined in accordance with the terms of such
other compensation arrangements or such other plans or programs.

     The term "Due Cause", as used herein, shall mean that (a) the Employee has
committed a willful, serious act, such as embezzlement, against the Corporation
intending to enrich himself at the expense of the Corporation or (b) the
Employee, in carrying out his duties hereunder, has been guilty of willful,
gross negligence (including competition as defined in Section 13, resulting in
either case in material harm to the Corporation (this provision shall not apply
to any particular instance which is merely the result of any good faith error in
judgment), (c) the willful and continued failure by Employee to substantially
perform his duties with the Corporation (other than any such failure

                                       -7-
<PAGE>
resulting from Employee's incapacity due to physical or mental illness), after a
demand for substantial performance is delivered to Employee by the Board which
specifically identifies the manner in which the Board believes that Employee has
not substantially performed his duties, or (d) the willful engaging by Employee
in gross misconduct materially and demonstrably injurious to the Corporation.
For purposes of this paragraph, no act, or failure to act, on Employee's part
shall be considered "willful" unless done, or omitted to be done, by Employee,
not in good faith and without reasonable belief that Employee's action or
omission was in the best interest of the Corporation.

     Notwithstanding the foregoing, Employee shall not be deemed to have been
terminated for Due Cause unless and until there shall have been delivered to him
a copy of a resolution duly adopted by the affirmative vote of a majority of the
entire membership of the Board at a meeting of the Board called and held for the
purpose (after reasonable notice to Employee and an opportunity for Employee,
together with his counsel, to be heard before the Board), finding that in the
good faith opinion of the Board Employee was guilty of conduct set forth above
and specifying the particulars thereof in detail.

     9.4 Termination by Corporation Other than for Due Cause. The foregoing
notwithstanding, the Corporation may terminate the Employee's employment for
whatever reason it deems appropriate, provided, however, that in the event such
termination is not due to permanent disability as provided in Section 9.2, or
based on Due Cause as provided in Section 9.3, the Employee will continue to
receive his salary as provided in Section 8 for the term of one year from the
date of such termination. During the period of salary continuation hereunder the
Employee will be entitled to continued benefit coverage and benefit credits as
provided in Section 6 hereof or the economic equivalent. Any such benefit
coverage, or economic equivalent thereto, will be offset by comparable coverage
provided to the Employee in connection with any subsequent employment.

     9.5 Termination by the Employee for Good Reason. Employee may terminate his
employment under this Agreement for Good Reason in which event the Corporation
shall still have the same obligations to Employee under this Agreement as
provided for in Section 9.4.

                  9.5.1  "Good Reason" shall mean:

                  (a) Without Employee's express written consent, the assignment
         to Employee of any duties inconsistent with his positions, duties,
         responsibilities and status with the Corporation immediately prior to a
         Change in Control, as hereinafter defined, or a change in his reporting
         responsibilities, title or offices as in effect immediately

                                       -8-
<PAGE>
         prior to a change in control, or any removal of Employee from or any
         failure to re-elect him to any of such positions, except in connection
         with the termination of his employment for Due Cause, Disability or
         Retirement or as a result of his death or by Employee other than for
         Good Reason;

                  (b) A reduction in Employee's base salary or benefits or a
         breach of the Corporation's obligations undertaken in this Agreement;

                  (c) In the event of the occurrence of a Change in Control,
         this Agreement may be terminated by Employee only upon the occurrence
         thereafter of one or more of the following events:

                           i. Any termination by the Corporation of the
                  Employment of Employee within three (3) years after a Change
                  in Control and prior to the date upon which Employee shall
                  have attained age 65, which termination shall be for any
                  reason other than for Due Cause or as a result of the death of
                  Employee or by reason of Employee's disability and the actual
                  receipt of disability benefits as provided in Section 9.2
                  hereof; or

                           ii. Termination by Employee of his employment with
                  the Corporation within three (3) years after a Change in
                  Control and upon the occurrence of any of the following
                  events:

                                    (A) Failure to elect or re-elect Employee,
                           or removal of Employee, as a director of the
                           Corporation (or any successor thereto), if Employee
                           shall have been a director of the Corporation
                           immediately prior to the Change in Control, or the
                           office of the Corporation which Employee held
                           immediately prior to a Change in Control;

                                    (B) A significant adverse change in the
                           nature or scope of the authorities, powers,
                           functions, responsibilities or duties attached to the
                           position with the Corporation which Employee had
                           immediately prior to the Change in Control, a
                           reduction in the aggregate of Employee's Base Pay and
                           Incentive Pay received from the Corporation, or the
                           termination of Employee's rights to any Employee
                           Benefit to which he was entitled immediately prior to
                           the Change in Control or a reduction in scope or
                           value thereof without the prior written consent of
                           Employee, any of which is not remedied within ten
                           (10) calendar days after receipt by the Corporation
                           of written notice from

                                       -9-
<PAGE>
                           Employee of such change, reduction or termination,
                           as the case may be;

                                    (C) A determination by Employee made in good
                           faith that as a result of a Change in Control and a
                           change in circumstances thereafter significantly
                           affecting his position, he has been rendered
                           substantially unable to carry out, or has been
                           substantially hindered in the performance of, any of
                           the authorities, powers, functions, responsibilities
                           or duties attached to his position immediately prior
                           to the Change in Control, which situation is not
                           remedied within ten (10) calendar days after receipt
                           by the Corporation of written notice from Employee of
                           such determination;

                                    (D) The liquidation, dissolution, merger,
                           consolidation or reorganization of the Corporation or
                           transfer of all or a significant portion of its
                           business and/or assets unless the successor or
                           successors (by liquidation, merger, consolidation,
                           reorganization or otherwise) to which all or a
                           significant portion of its business and/or assets
                           have been transferred (directly or by operation of
                           law) shall have assumed all duties and obligations of
                           the Corporation under this Agreement; or

                                    (E) The Corporation shall relocate its
                           principal executive offices or require Employee to
                           have as his principal location of work any location
                           which is in excess of 100 miles from the location
                           thereof immediately prior to the Termination Date or
                           to travel away from his office in the course of
                           discharging his responsibilities or duties hereunder
                           more than thirty (30) consecutive calendar days or an
                           aggregate of more than sixty (60) calendar days in
                           any consecutive 365-calendar day period without in
                           either case his prior consent.

                  (d) Subsequent to a change in control of the Corporation, the
         failure by the Corporation to obtain the assumption of the obligation
         to perform this Agreement by any successor; or:

                  (e) Subsequent to a change in control of the Corporation, any
         purported termination of Employee's employment which is not effected
         pursuant to a Notice of Termination satisfying the requirements of
         Section 9.7 hereof.

     9.5.2 Change in Control. For purposes of this Agreement, a "Change in
Control" shall have occurred if at any time

                                      -10-
<PAGE>
during the term (as that term is hereafter defined), any of the following events
shall occur:

                  i. The Corporation is merged, or consolidated, or reorganized
         into or with another corporation or other legal person, and as a result
         of such merger, consolidation or reorganization less than 51% of the
         combined voting power of the then-outstanding securities of such
         corporation or person immediately after such transaction are held in
         the aggregate by the holders of voting securities of the Corporation
         immediately prior to such transaction;

                  ii. The Corporation sells all or substantially all of its
         assets to any other corporation or other legal person and thereafter,
         less than 51% of the combined voting power of the then-outstanding
         voting securities of the acquiring or consolidated entity, which are
         held in the aggregate by the holders of voting securities of the
         Corporation immediately prior to such sale;

                  iii. There is a report filed after the date of this Agreement
         on Schedule 13 D or Schedule 14 D-1 (or any successor schedule, form or
         report), each as promulgated pursuant to the Securities Exchange Act of
         1934 (the "Exchange Act") disclosing that any person (as the term
         "person" is used in Section 13(d)(3) or Section 14(d)(2) of the
         Exchange Act) has become the beneficial owner (as the term "beneficial
         owner" is defined under Rule 13 d-3 or any successor rule or regulation
         promulgated under the Exchange Act) representing 25% or more of the
         combined voting power of the then-outstanding voting securities of the
         Corporation;

                  iv. The Corporation shall file a report or proxy statement
         with the Securities and Exchange Commission pursuant to the Exchange
         Act disclosing in response to Item 1 of Form 8-K thereunder or Item
         5(f) of Schedule 14 A thereunder (or any successor schedule, form or
         report or item therein) that the change in control of the Corporation
         has or may have occurred or will or may occur in the future pursuant to
         any then-existing contract or transaction; or

                  v. During any period of two consecutive years, individuals who
         at the beginning of any such period constitute the directors of the
         Corporation cease for any reason to constitute at least a majority
         thereof unless the election or the nomination for election by the
         Corporation's shareholders of each director of the Corporation first
         elected during such period was approved by a vote of at least
         two-thirds of the directors of the Corporation then still in office who
         were directors of the Corporation at the beginning of such period.

                                      -11-
<PAGE>
     9.6 Termination by Employee by Voluntary Resignation. Employee may
terminate this Agreement upon ninety (90) days notice to the Corporation, in
which event the Corporation shall be obligated to pay him his total remuneration
and other benefits up to the date of termination only.

     9.7 Notice of Termination. Any Notice of Termination by the Corporation
pursuant to Section 9.4 or by Employee pursuant to Section 9.5 or 9.6 shall be
communicated by written Notice of Termination to the other party hereof. For
purposes of this Agreement, a "Notice of Termination" shall mean a notice which
shall indicate the specific termination provision in this Agreement relied upon
and shall set forth in reasonable detail the facts and circumstances claimed to
provide a basis for termination of Employee's employment under the provision so
indicated.

     9.8 Date of Termination. "Date of Termination" shall mean:

          (a) If Employee's employment is terminated pursuant to Section 9.5 or
     9.6, the date specified in the Notice of Termination, and

          (b) if Employee's employment is terminated for any other reason, the
     date on which a Notice of Termination is given;

10.  Legal Expenses:

     In the event that Employee incurs legal expenses in contesting any
provision of this Agreement and such contest results in a determination that the
Corporation has breached any of its obligations hereunder, Employee shall be
reimbursed by the Corporation for such legal expenses.

Agreed:

XOMA CORPORATION                            EMPLOYEE
By: /s/Steven C. Mendell                    /s/John L. Castello
Steven C. Mendell                           John L. Castello
Title: Chairman of the Board

                                      -12-





                              EMPLOYMENT AGREEMENT

     This Employment Agreement ("Agreement"), made and effective this 28th day
of March, 1997, by and between XOMA CORPORATION ("XOMA" or the "Company"), a
Delaware corporation with its principal office at 2910 Seventh Street, Berkeley,
California, and Patrick J. Scannon, M.D, Ph.D., ("Executive"), an individual
residing at 176 Edgewood, San Francisco, California.

     WHEREAS, the Company wishes to enter into this Agreement to assure the
Company of the continued services of Executive; and

     WHEREAS, Executive is willing to enter into this Agreement and to serve in
the employ of the Company upon the terms and conditions hereinafter provided;

     NOW, THEREFORE, in consideration of the mutual covenants herein contained,
the parties hereto hereby agree as follows:

     1. Employment. The Company agrees to employ Executive, and Executive agrees
to enter the employ of the Company, for the period referred to in Section 3
hereof and upon the other terms and conditions herein provided.

     2. Position and Responsibilities. The Company agrees to employ Executive in
the position of Chief Scientific and Medical Officer, and Executive agrees to
serve as Chief Scientific and Medical Officer, for the term and on the
conditions hereinafter set forth. Executive agrees to perform such services not
inconsistent with his position as shall from time to time be assigned to him by
the Chairman of the Board, President and Chief Executive Officer of the Company
(the "Chairman").

     3. Term and Duties.

     (a) Term of Employment. This Agreement shall become effective and the term
of employment pursuant to this Agreement shall commence on March 28, 1997 and
will continue for one (1) year until March 27, 1998, when it will terminate
unless it is extended by mutual written consent of Executive and the Company or
unless Executive's employment is terminated by the Company or he resigns from
the Company's employ as described herein.

     (b) Duties. During the period of his employment hereunder Executive shall
serve the Company as its Chief Scientific and Medical Officer, and except for
illnesses, vacation periods and reasonable leaves of absence, Executive shall
devote all of his business time, attention, skill and efforts to the faithful
performance of his duties hereunder.

     So long as Executive is Chief Scientific and Medical Officer of the
Company, he will discharge all duties incidental to such office and such further
duties as may be reasonably

                                        1


<PAGE>


assigned to him from time to time by the Chairman.

     4. Compensation and Reimbursement of Expenses.

     (a) Compensation. For all services rendered by Executive as Chief
Scientific and Medical Officer during his employment under this Agreement, the
Company shall pay Executive as compensation a salary at a rate of not less than
$300,000 per annum. All taxes and governmentally required withholding shall be
deducted in conformity with applicable laws.

     (b) Loan. In further consideration of Executive's agreement to the terms
hereof, the Company has agreed to a one year extension of a loan previously
provided to Executive in the principal amount of $251,297.46 (the "Loan") on the
terms and subject to the conditions set forth herein. On the date on which
Executive and the Company agreed that the Loan was to be funded (the "Loan
Date"), Executive executed a promissory note in the form attached hereto as
Exhibit A evidencing the Loan and a pledge agreement in the form attached hereto
as Exhibit B granting to the Company a first priority security interest in all
of the outstanding shares of Common Stock owned by Executive on the effective
date of this Agreement, whereupon the Company did lend to Executive the
principal amount of the Loan. The full amount of the Loan will be repaid by
Executive as soon as reasonably practicable and in any event no later than March
27, 1998, or on demand following any earlier termination of or resignation by
Executive. Interest will accrue on the Loan at a rate per annum equal to the
prime rate, as published in The Wall Street Journal on the Loan Date, and will
be payable as and when the Loan is repaid.

     (c) Reimbursement of Expenses. The Company shall pay or reimburse Executive
for all reasonable travel and other expenses incurred by Executive in performing
his obligations under this Agreement in a manner consistent with past Company
practice. The Company further agrees to furnish Executive with such assistance
and accommodations as shall be suitable to the character of Executive's position
with the Company, adequate for the performance of his duties and consistent with
past Company practice.

     5. Participation in Benefit Plans. The payments provided in Section 4
hereof are in addition to benefits Executive is entitled to under any group
hospitalization, health, dental care, disability insurance, surety bond, death
benefit plan, travel and/or accident insurance, other allowance and/or executive
compensation plan, including, without limitation, any senior staff incentive
plan, capital accumulation and termination pay programs, restricted or
non-restricted stock purchase plan, stock option plan, retirement income or
pension plan or other present or future group employee benefit plan or program
of the Company for which key executives are or shall become eligible, and
Executive shall be eligible to receive during the period of his employment under
this Agreement, and during any subsequent

                                        2


<PAGE>


period(s) for which he shall be entitled to receive payment from the Company
under paragraph 6(b) below, all benefits and emoluments for which key executives
are eligible under every such plan or program to the extent permissible under
the general terms and provisions of such plans or programs and in accordance
with the provisions thereof.

     6. Payments to Executive Upon Termination of Employment.

     (a) Termination. Upon the occurrence of an event of termination (as
hereinafter defined) during the period of Executive's employment under this
Agreement, the provisions of this paragraph 6(a) and paragraph 6(b) shall apply.
As used in this Agreement, an "event of termination" shall mean and include any
one or more of the following:

               (i) The termination by the Company of Executive's employment
          hereunder for any reason other than pursuant to paragraph 6(c); or

               (ii) Executive's resignation from the Company's employ, upon not
          less than thirty (30) days' prior written notice.

     (b) Continuation of Salary and Other Benefits. Upon the occurrence of an
event of termination under paragraph 6(a), the Company (i) shall, subject to the
provisions of Section 7 below, pay Executive, or in the event of his subsequent
death, his beneficiary or beneficiaries of his estate, as the case may be, as
severance pay or liquidated damages, or both, semi-monthly for a period of
twelve (12) months following the event of termination (the "Severance Payment
Period"), a sum equal to his current salary in effect at the time of the event
of termination, but in no case less than $300,000 per annum, (ii) shall continue
to provide the other benefits referred to in Section 5 hereof until the end of
the Severance Payment Period or until Executive becomes employed elsewhere,
whichever is earlier, and (iii) shall continue to provide the benefits provided
for in paragraph 4(c) to the extent of expenses incurred but not reimbursed
prior to the event of termination. Such payments shall commence on the last day
of the next regular pay period following the date of the event of termination,
or, at the election of the Company, may be paid in one lump sum or in such other
installments as may be mutually agreed between the Company and Executive or, in
the event of his subsequent death, his beneficiary or beneficiaries or legal
representative, as the case may be.

     (c) Other Termination of Employment. Notwithstanding paragraphs 6(a) and
(b) or any other provision of this Agreement to the contrary, if on or after the
date of this Agreement and prior to the end of the term hereof:

               (i) Executive has been convicted of any crime or offense
          constituting a felony under applicable law, including, without
          limitation, any act of dishonesty

                                        3


<PAGE>


          such as embezzlement, theft or larceny;

               (ii) Executive shall act or refrain from acting in respect of any
          of the duties and responsibilities which have been assigned to him in
          accordance with this Agreement and shall fail to desist from such
          action or inaction within ten (10) days (or such longer period of
          time, not exceeding ninety (90) days, as Executive shall in good faith
          and the exercise of reasonable efforts require to desist from such
          action or inaction) after Executive's receipt of notice from the
          Company of such action or inaction and the Board of Directors
          determines that such action or inaction constituted gross negligence
          or a willful act of malfeasance or misfeasance of Executive in respect
          of such duties; or

               (iii) Executive shall breach any material term of this Agreement
          and shall fail to correct such breach within ten (10) days (or such
          longer period of time, not exceeding ninety (90) days, as Executive
          shall in good faith and the exercise of reasonable efforts require to
          cure such breach) after Executive's receipt of notice from the Company
          of such breach;

then, and in each such case, the Company shall have the right to give notice of
termination of Employee's services hereunder as of a date (not earlier than
fourteen (14) days from such notice) to be specified in such notice and this
Agreement (other than the provisions of Section 7 hereof) shall terminate on
such date.

     7. Post-Termination Obligations. All payments and benefits to Executive
under this Agreement shall be subject to Executive's compliance with the
following provisions during the term of his employment and for the Severance
Payment Period:

     (a) Confidential Information and Competitive Conduct. Executive shall not,
to the detriment of the Company, disclose or reveal to any unauthorized person
any trade secret or other confidential information relating to the Company or
its affiliates or to any businesses operated by them, and Executive confirms
that such information constitutes the exclusive property of the Company.
Executive shall not otherwise act or conduct himself to the material detriment
of the Company or its affiliates, or in a manner which is inimical or contrary
to the interests thereof, and shall not, directly or indirectly, engage in,
enter the employ of or render any service to any person, firm or business in
direct competition with any part of the business being conducted by the Company;
provided, however, that Executive's ownership less than five percent (5%) of the
outstanding stock of a corporation shall not be itself be deemed to constitute
such competition. Executive recognizes that the possible restrictions on his
activities which may occur as a result of his performance of his obligations
under this paragraph 7(a) are required for the reasonable protection of the
Company and its investments. For purposes hereof, "direct competition"

                                        4


<PAGE>


means the pursuit of one or more of the same therapeutic or diagnostic
indications utilizing a substantially similar scientific basis.

     (b) Failure of Executive to Comply. If, for any reason other than death or
disability, Executive shall, without written consent of the Company, fail to
comply with the provisions of paragraph 7(a) above, his rights to any future
payments or other benefits hereunder shall terminate, and the Company's
obligations to make such payments and provide such benefits shall cease.

     (c) Remedies. Executive agrees that monetary damages would not be adequate
compensation for any loss incurred by the Company by reason of a breach of the
provisions of this Section 7 and hereby agrees to waive the defense in any
action for specific performance that a remedy at law would be adequate.

     8. Effect of Prior Agreements. This Agreement contains the entire
understanding between the parties hereto and supersedes any prior employment
agreements between the Company and Executive.

     9. General Provisions.

     (a) Binding Agreement. This Agreement shall be binding upon, and inure to
the benefit of, Executive and the Company and their respective permitted
successors and assigns.

     (b) Legal Expenses. In the event that Executive incurs legal expenses in
contesting any provision of this Agreement and such contest results in a
determination that the Company has breached any of its obligations hereunder,
Executive shall be reimbursed by the Company for such legal expenses.

     10. Successors and Assigns.

     (a) Assignment by the Company. This Agreement shall be binding upon and
inure to the benefit of the successors and assigns of the Company and, unless
clearly inapplicable, reference herein to the Company shall be deemed to include
its successors and assigns.

     (b) Assignment by Executive. Executive may not assign this Agreement in
whole or in part.

     11. Modification and Waiver.

     (a) Amendment of Agreement. This Agreement may not be modified or amended
except by an instrument in writing signed by the parties hereto.

     (b) Waiver. No term or condition of this Agreement shall be deemed to have
been waived except by written instrument of the party charged with such waiver.
No such written waiver shall be deemed a continuing waiver unless specifically
stated

                                        5


<PAGE>


therein, and each such waiver shall operate only as to the specific term or
condition waived.

     12. Severability. In the event any provision of this Agreement or any part
hereof is held invalid, such invalidity shall not affect any remaining part of
such provision or any other provision. If any court construes any provision of
this Agreement to be illegal, void or unenforceable because of the duration or
the area or matter covered thereby, such court shall reduce the duration, area
or matter of such provision, and, in its reduced form, such provision shall then
be enforceable and shall be enforced.

     13. Governing Law. This Agreement has been executed and delivered in the
State of California, and its validity interpretation, performance, and
enforcement shall be governed by the laws of said State.

     IN WITNESS WHEREOF, XOMA has caused this Agreement to be executed by its
duly authorized officer, and Executive has signed this Agreement, all as of the
day and year first above written.

                                  XOMA CORPORATION

                                  /S/Christopher J. Margolin
                                  Christopher J. Margolin
                                  Vice President, General Counsel
                                  and Secretary

                                  /s/Patrick J. Scannon
                                  Patrick J. Scannon, M.D., Ph.D.
<PAGE>
                                    EXHIBIT A

                                 PROMISSORY NOTE

$251,297.46                                               Berkeley, California
                                 March 28, 1997

     FOR VALUE RECEIVED, the undersigned (the "Obligor") hereby unconditionally
promises to pay to the order of XOMA Corporation, a Delaware corporation (the
"Obligee"), the principal sum of TWO HUNDRED FIFTY-ONE THOUSAND TWO HUNDRED
NINETY-SEVEN DOLLARS AND FORTY-SIX CENTS ($251,297.46) (the "Principal Amount")
together with interest from the date hereof at a rate per annum of six percent
(6%) on the earlier of (a) five (5) days after the demand of the Obligee if the
Obligor ceases to be employed by the Obligee or (b) the 27th day of March, 1998.
Said principal sum, and/or any accrued interest, may be prepaid in whole or in
part without premium or penalty.

     1. It is hereby understood and agreed that if default be made in the
payment of the Principal Amount or of interest accrued and unpaid thereon, then
the Obligee may exercise any remedies available at law or in equity, including,
but not limited to, foreclosure upon the shares of Obligee's common stock which
have hereupon been pledged by the Obligor to the Obligee as security for the
Obligor's obligations hereunder pursuant to a Pledge Agreement, but shall not be
obligated to proceed first against such collateral and may proceed directly on
this Promissory Note. In the event of any such default, the Obligee shall be
entitled also to all costs of collection, including the reasonable fees of an
attorney. In the event the Obligee proceeds against the collateral and the
proceeds of the collateral are inadequate to pay any amounts due on this
Promissory Note, the Obligor shall remain liable for any deficiency. In
addition, and without limitation of any other provision of this Paragraph, in
the event of any default described above, the Obligor authorizes and requests
the Obligee to deduct and withhold from compensation otherwise payable by the
Obligee to the Obligor an amount equal to the defaulted payment of the Principal
Amount and/or of interest accrued and unpaid thereon; provided however, that the
Obligee may not so deduct more than fifty (50) percent of any payment of
compensation otherwise due the Obligor.

     2. If application shall be made for the appointment of a receiver, trustee
or liquidator of the Obligor or any of his property, or if the Obligor shall
make a general assignment for the benefit of creditors, be adjudicated a
bankrupt or file a voluntary petition in bankruptcy or seek reorganization of
any arrangement with creditors, the Obligee may declare this Promissory Note to
be due and payable, whereupon this Promissory Note shall forthwith become due
and payable without presentment,

                                        1


<PAGE>


demand, protest, or notice of protest, notice of dishonor, notice of nonpayment
or any other notice of any kind, all of which are hereby expressly waived.

     3. No delay or omission on the part of the Obligee in exercising any right
hereunder shall operate as a waiver of such right or of any other right, nor
shall any delay, omission or waiver on any one occasion be deemed a bar to or
waiver of the same or any other right on any future occasion.

     4. If any provision of this Promissory Note should be found to be invalid
or unenforceable, all other provisions shall nevertheless remain in full force
and effect. This Promissory Note and any of its terms may be changed, waived or
terminated only by a written instrument signed by the party against which
enforcement of that change, waiver or termination is sought. The rights and
obligations of the parties hereunder shall be governed by and interpreted and
enforced in accordance with the substantive laws of the State of California,
without giving effect to principles of conflicts of law.

     WITNESS the due execution hereof as of the date first above written.

                                    Patrick J. Scannon, M.D., Ph.D.

                                        2


<PAGE>


                                    EXHIBIT B

                                PLEDGE AGREEMENT

     PLEDGE AGREEMENT dated April 15, 1993, between Patrick J. Scannon, M.D.,
Ph.D. (the "Pledgor"), and XOMA Corporation, a Delaware corporation (the
"Pledgee").

     WHEREAS, the Pledgor is the owner of 69,993 shares (the "Pledged Shares")
of Common Stock, par value $0.0005 per share, issued by the Pledgee; and

     WHEREAS, the Pledgee has agreed to loan the Pledgee $290,539.46 in
connection with the certain liabilities related to the Pledged Shares (the
"Loan"), and the Pledgor has simultaneously with the execution of this Agreement
executed a Promissory Note (the "Note") evidencing such indebtedness;

     NOW THEREFORE, in consideration of the premises and in order to induce the
Pledgee to make the Loan, the Pledgor hereby agrees with the Pledgee as follows:

     SECTION 1. Pledge. The Pledgor hereby pledges to the Pledgee, and grants to
the Pledgee a security interest in, the Pledged Shares and any and all proceeds
therefrom.

     SECTION 2. Security for Obligations. This Agreement secures the payment of
all obligations of the Pledgor to the Pledgee now or hereafter existing pursuant
to the Loan and the Note, whether for principal, interest, fees, expenses or
otherwise (all such obligations of the Pledgor being the "Obligations").

     SECTION 3. Delivery of Pledged Shares. All certificates or instruments
representing or evidencing the Pledged Shares shall be delivered to and held by
or on behalf of the Pledgee pursuant hereto and shall be in suitable form for
transfer by delivery, or shall be accompanied by duly executed instruments of
transfer or assignment in blank, all in forms and substance satisfactory to the
Pledgee. In addition, the Pledgee shall have the right at any time to exchange
certificates or instruments representing or evidencing Pledged Shares for
certificates or instruments of smaller or larger denominations.

     SECTION 4. Representations and Warranties. The Pledgor represents and
warrants as follows:


<PAGE>


                                       -2-

     (a) The Pledgor is the legal and beneficial owner of the Pledged Shares
free and clear of any lien, security interest, option or other charge or
encumbrance except for the security interest created by this Agreement.

     (b) The pledge of the Pledged Shares pursuant to this Agreement creates a
valid and perfected first priority security interest in the Pledged Shares,
securing the payment of the Obligations.

                  SECTION 5. Further Assurances. The Pledgor agrees that at any
time and from time to time, at the expense of the Pledgor the Pledgor will
promptly execute and deliver all further instruments and documents, and take all
further action, that may be necessary or appropriate, or that the Pledgee may
reasonably request, in order to perfect and protect any security interest
granted or purported to be g ranted hereby or to enable the Pledgee to exercise
and enforce its rights and remedies hereunder with respect to any Pledged
Shares.

     SECTION 6. Voting Rights; Dividends; Etc. (a) So long as no default exists
under the Note:

          (i) The Pledgor shall be entitled to exercise any and all voting and
     other consensual rights pertaining to the Pledged Shares.

          (ii) The Pledgor shall be entitled to receive and retain any and all
     dividends in respect of the Pledged Shares, provided, however, that any and
     all dividends paid or payable other than in cash in respect of, and
     instruments and other property received, receivable or otherwise
     distributed in respect of, or in exchange for, any Pledged Shares, and any
     and all dividends and other distributions paid or payable in cash in
     respect of any Pledged Collateral in connection with a partial or total
     liquidation or dissolution or in connection with a reduction of capital,
     capital surplus or paid-in-surplus shall be delivered to the Pledgee to
     hold as collateral as if such were Pledged Shares (such Collateral,
     together with the Pledged Shares, the "Pledged Collateral") and shall, if
     received by the Pledgor, be received in trust for the benefit of the
     Pledgee, be segregated from the other property or funds of the Pledgor, and
     be forthwith delivered to the Pledgee as Pledged Collateral in the same for
     as so received (with any necessary indorsement).


<PAGE>


                                       -3-

     (b) Upon the occurrence of a default under the Note, all rights of the
Pledgor to exercise the voting and other consensual rights which it would
otherwise be entitled to exercise pursuant to Section y(a)(i) and to receive the
dividends which it would otherwise be authorized to receive and retain pursuant
to Section (a)(ii) shall cease, and all such rights shall thereupon become
vested in the Pledgee who shall thereupon have the sole right to exercise such
voting and other consensual rights and to receive and hold as Pledged collateral
such dividends, and all dividends which are received by the Pledgor contrary to
the provisions of this Section (b) shall be received in trust for the benefit of
the Pledgee, shall be segregated from other funds of the Pledgor and shall be
forthwith paid over the Agent as Pledged Collateral in the same form as so
received with any necessary indorsement).

     SECTION 7. Pledgee Appointed Attorney-in-Fact. The Pledgor hereby
irrevocably appoints the Pledgee the Pledgor's attorney-in-fact, with full
authority in the place and stead of the Pledgor and in the name of the Pledgor
or otherwise, from time to time in the Pledgee's discretion, to take any action
and to execute any instrument which the Pledgee may deem necessary or advisable
to accomplish the purposes of this Agreement, including, without limitation, to
receive, indorse and collect all instruments made payable to the Pledgor
representing any dividend or other distribution in respect of the Pledge Shares
and to give full discharge for the same, when and to the extent permitted by
this Agreement.

     SECTION 8. Pledgee May Perform. If the Pledgor fails to perform any
agreement contained herein, the Pledgee may itself perform, or cause performance
of, such agreement, and the expenses of the Pledgee incurred in connection
therewith shall be payable by the Pledgor under Section 11.

     SECTION 9. Reasonable Care. The Pledgee shall be deemed to have exercised
reasonable care in the custody and preservation of the Pledged Collateral in its
possession if such Pledged Collateral is accorded treatment substantially
equivalent to that which the Pledgee accords its own property, it being
understood that the Pledgee shall not have responsibility for taking any
necessary steps to preserve rights against any parties with respect to any of
the Pledged Collateral.

     SECTION 10. Remedies upon Default. If any default under the Note shall have
occurred:


<PAGE>


                                       -4-

     (a) The Pledgee may exercise in respect of the Pledged Collateral, in
addition to other rights and remedies provided for herein or otherwise available
to it, all the rights and remedies of a secured party on default under the
Uniform Commercial Code (the "Code") in effect in the State of California at
that time (in compliance with all applicable securities laws), and the Pledgee
may also, without notice except as specified below, sell (in compliance with all
applicable securities laws) the Pledged collateral or any part thereof in one or
more parcels at public or private sale, at any exchange, broker's board, for
cash, on credit or for future delivery, and at such price or prices and upon
such other terms as the Pledgee may deem commercially reasonable. The Pledgor
agrees that, to the extent notice of sale shall be required by law, at least ten
days' notice to the Pledgor of the time and place of any public sale or the time
after which any private sale is to be made shall constitute reasonable
notification. The Pledgee shall not be obligated to make any sale of Pledged
Collateral regardless of notice of sale having been given.

     (b) Any cash held by the Pledgee as Pledged Collateral and all cash
proceeds received by the Pledgee in respect of any sale of, collection from, or
other realization upon all or any part of the Pledged Collateral may, in the
discretion of the Pledgee, be held by the Pledgee as collateral for, and/or then
or at any time thereafter applied (after payment of any amounts payable to the
Pledgee pursuant to Section 11) in whole or in part by the Pledgee against all
or any part of the Obligations in such order as the Pledgee shall elect. Any
surplus of such cash or cash proceeds held by the Pledgee and remaining after
payment in full of all the Obligations shall be paid over the Pledgor or to
whomsoever may be lawfully entitled to receive such surplus.

     SECTION 11. Expenses. The Pledgor will upon demand pay to the Pledgee the
amount of any and all reasonable expenses, including the fees and expenses of
its counsel and of any agents, which the Pledgee may incur in connection with
(i) the custody of, or the sale or other realization upon, any of the Pledged
collateral, (ii) the exercise or enforcement of any of the rights of the
Pledgee, or (iii) the failure by the Pledgor to perform or observe any of the
provisions hereof.


<PAGE>


                                       -5-

     SECTION 12. Security Interest Absolute. All rights of the Pledgee and
security interests hereunder, and all obligations of the Pledgor hereunder,
shall be absolute and unconditional.

     SECTION 13. Amendments, Etc. No amendment or waiver of any provision of
this Agreement nor consent to any departure by the Pledgor herefrom shall in any
event be effective unless the same shall be in writing and signed by the
Pledgee, and then such waiver or consent shall be effective only in the specific
instance and for the specific purpose for which given.

     SECTION 14. Addresses for Notices. Any notice or other communication to be
given or made to the Pledgee hereunder shall be sent or otherwise communicated
to the Pledgee at Xoma Corporation, Attention: Christopher Margolin, 1920
Seventh Street, Berkeley, California 94170, telecopy (510) 649-7571 or such
other address and/or for such other attention as may be notified to the Pledgor
in accordance with this Section. Any notice or other communication to be given
to the Pledgor hereunder shall be sent or otherwise communicated to the Pledgor
at 176 Edgewood, San Francisco, California 94117, or such other address and/or
for such other attention as may be notified to the Pledgee in accordance with
this Section. Any notice or other communication to be given or made pursuant to
this Agreement may be given or made personally or by registered first class mail
or by telecopier and shall be effective when actually received.

     SECTION 15. Continuing Security Interest; Assignments. This Agreement shall
create a continuing security interest in the Pledged Collateral and shall (I)
remain in full force and effect until payment in full of the Obligations and
(ii) inure, together with the rights and remedies of the Pledgee hereunder, to
the benefit of the Pledgee, and successors, transferees and assigns. Upon the
payment in full of the Obligations, the Pledgor shall be entitled to the return,
upon its request and at its expense, of such of the Pledged Collateral as shall
not have been sold or otherwise applied pursuant to the terms hereof.

     SECTION 16. Governing Law; Terms. This Agreement shall be governed by and
construed in accordance with the laws of the State of California, except as
required by mandatory provisions of law and except to the extent that the
validity or perfection of the security interest hereunder, or remedies
hereunder, in respect of any particular Pledged Collateral are


<PAGE>


                                       -6-

governed by the laws of a jurisdiction other than the State of California.
Unless otherwise defined herein, terms defined in Article 9 of the Uniform
Commercial Code in the State of California are used herein as therein defined.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered by their respective officers thereunto duly
authorized, as of the date first above written.

                                     /s/ Patrick J. Scannon
                                     PATRICK J. SCANNON, M.D., Ph.D.

                                     XOMA CORPORATION

                                     By /s/ John L. Castello
                                     John L. Castello
                                     Chairman of the Board,
                                     President and Chief
                                     Executive Officer




                                XOMA CORPORATION

                                890 HEINZ STREET

                           TRIPLE NET LABORATORY LEASE

                                Table Of Contents

Paragraph Title                                                            Page

1.0       BASIC LEASE TERMS .................................................1

          1.1      Commencement Of Lease ....................................1
          1.2      Lease Term ...............................................1
          1.3      Monthly Rent .............................................1
          1.4      Security Deposit .........................................1
          1.5      Use ......................................................1

2.0       PREMISES ..........................................................2

3.0       TERM ..............................................................2


          3.1      Commencement .............................................2
          3.2      Option To Terminate ......................................2
          3.3      Option To Extend Term ....................................2
          3.4      Term .....................................................2
          3.5      Fair Market Lease Rate ...................................2

4.0       RENT ..............................................................3

          4.1      Monthly Rent .............................................3
          4.2      Rent Adjustment ..........................................3
          4.3      Mode of Payment ..........................................4
          4.4      Triple Net Lease .........................................4
          4.5      Estimated Payments .......................................4
          4.6      Security Deposit .........................................5
          4.7      Late Charges .............................................5

5.0       TAXES .............................................................6

          5.1      Real Property Taxes ......................................6
          5.2      Personal Property Taxes ..................................6

6.0       INSURANCE .........................................................6

          6.1      Property/Rental Insurance -
                   Premises .................................................6
          6.2      Property Insurance - Fixtures And
                   Inventory ................................................7
          6.3      Lessor's Liability Insurance .............................7
          6.4      Lessee's Liability Insurance .............................7
          6.5      Waiver Of Subrogation ....................................7
          6.6      Indemnification ..........................................8
          6.7      Plate Glass Replacement ..................................8
          6.8      Workers' Compensation Insurance ..........................8


                                       -i-


<PAGE>
                                                                            Page

7.0       MAINTENANCE .......................................................8

          7.1        Premises ...............................................8
          7.2        Building ...............................................9
          7.3        Common Areas ...........................................9
          7.4        Alterations, Changes And Additions
                     By Lessee ..............................................9
          7.5        Plumbing ...............................................10
          7.6        Liens ..................................................10

8.0       MANAGEMENT ........................................................10

9.0       UTILITIES AND SERVICES ............................................11

10.0      USE OF PREMISES ...................................................11

          10.1       Use ....................................................11
          10.2       Common Areas ...........................................11
          10.3       Uses Prohibited ........................................11
          10.4       Lessee's Warranty ......................................12

11.0      DEFAULT PROVISIONS ................................................13

          11.1       Insolvency .............................................13
          11.2       Non-Payment, Breach Or Vacating ........................13
          11.3       Default Under Other Leases .............................13
          11.4       Lessor's Right To Relet ................................13
          11.5       Right To Terminate .....................................14
          11.6       Default By Lessor ......................................14

12.0      EXPIRATION OR TERMINATION .........................................14

          12.1       Surrender Of Possession ................................14
          12.2       Holding Over ...........................................14
          12.3       Voluntary Surrender ....................................14

13.0      CONDEMNATION OF PREMISES ..........................................15

          13.1       Total Condemnation .....................................15
          13.2       Partial Condemnation ...................................15
          13.3       Award To Lessee ........................................15

14.0      ENTRY BY LESSOR ...................................................16

15.0      INDEMNIFICATION ...................................................16

16.0      ASSIGNMENT AND SUBLETTING .........................................16

17.0      DAMAGE OR DESTRUCTION .............................................17

          17.1       Right To Termination On Destruction
                     Of Premises ............................................17
          17.2       Repairs By Lessor ......................................17
          17.3       Reduction Of Rent During Repairs .......................17
          17.4       Arbitration ............................................17


                                       ii-


<PAGE>
                                                                            Page

          17.5       Lessor's Overriding Right To
                     Terminate ..............................................18

18.0      OPTION TO PURCHASE PREMISES .......................................18

19.0      MISCELLANEOUS PROVISIONS ..........................................20

          19.1       Waiver .................................................20
          19.2       Successors And Assigns .................................20
          19.3       Notices ................................................20
          19.4       Partial Invalidity .....................................20
          19.5       Number And Gender ......................................20
          19.6       Descriptive Headings ...................................20
          19.7       Time Is Of The Essence .................................20
          19.8       Entire Agreement .......................................20
          19.9       Memorandum Of Lease ....................................21
          19.10      Applicable Law .........................................21
          19.11      Corporate Authority ....................................21
          19.12      Litigation Expense .....................................21
          19.13      Subordination Of Leasehold .............................21
          19.14      Lessee's Certificate ...................................21
          19.15      Attornment .............................................22
          19.16      Day ....................................................22
          19.17      Brokers ................................................22

         EXHIBIT A - DESCRIPTION OF THE PREMISES

                                      -iii-


<PAGE>
                                XOMA CORPORATION

                                890 HEINZ STREET

                           TRIPLE NET LABORATORY LEASE

     LEASE made and entered into this 22 day of July 1987, between SEVENTH
STREET PROPERTIES ("Lessor") and XOMA CORPORATION ("Lessee").

                                R E C I T A L S:

     A. Lessor and Lessee entered into an earlier Lease (the "Original Lease")
for the Premises described herein.

     B. Concurrently with the execution of this Lease, Lessee is entering into
three other leases with Seventh Street Properties II, an affiliate of Lessee,
for approximately 35,000 square feet in Building E, approximately 20,000 square
feet in Building F and approximately 6,720 square feet in Building C at the
Aquatic Park Center (referred to respectively as the "Building E Lease",
"Building F Lease" and "Building C Lease").

     C. In connection with Lessee's leasing of such additional space in
Buildings E, F and C, and as partial consideration therefor, Lessor and Lessee
desire to amend the terms of the Original Lease effective as of the Commencement
Date referenced below and to restate the Original Lease in its entirety below to
include such amended terms.

     D. The Building E Lease, the Building C Lease and this Lease are intended
to be read together so that a breach of one is deemed to be a breach of the
other.

                               A G R E E M E N T:

     NOW, THEREFORE, the parties hereby agree as follows:

     1.0 BASIC LEASE TERMS.

        1.1     Commencement Of Lease: The term of this Lease shall commence
                October 1, 1987.

        1.2     Lease Term: Through April 30, 2003.

        1.3     Monthly Rent: $22,333.

        1.4     Security Deposit: $22,333.

        1.5     Use: Pharmaceutical manufacturing, offices, laboratories,
                shipping and receiving relating to pharmaceutical products.

        2.0     PREMISES.

     Lessor hereby leases to Lessee that certain building and real property
located at 890 Heinz Street, Berkeley, California (the "Premises"). The building
on the Premises

                                       -1-


<PAGE>


constitutes approximately 24,275 square feet of leaseable space. Exhibit A
attached hereto further describes the Premises being leased hereby.

     3.0 TERM.

     3.1 Commencement. The Lease shall commence on the date specified in
Paragraph 1.1 above (the "Commencement Date") and shall continue thereafter for
the term specified in Paragraph 1.2 above (the "Initial Term"), unless sooner
terminated pursuant to this Lease.

     3.2 Option To Terminate. Lessee is hereby granted an option to terminate
the Lease effective April 30, 1998 by giving written notice to Lessor of
Lessee's intent to terminate (the "Termination Notice") on or before July 31,
1997.

     3.3 Option To Extend Term. Lessee is hereby granted an option to extend the
term for a five year period following the expiration of the Initial Term (the
"Option Term") by giving written notice to the Lessor of Lessee's intent to
exercise such option (the "Option Notice") at least 270 days before the
expiration of the Initial Term. The Option Term shall be on the same terms and
conditions in effect immediately before the end of the Initial Term, except that
the rent shall be set at 95% of the fair market lease rate for comparable space
in the Berkeley area, provided that in no event shall the rental rate for the
Option Term be less than the rental rate as of the last day of the Initial Term.
Notwithstanding anything to the contrary above, if Lessee is in default in the
payment of rent, in the making of other payments required to be made by Lessee
under this lease, or otherwise under this Lease on the date the Option Notice is
delivered to Lessor or on the date the Option Term is to commence, the Option
Term shall not commence and this Lease shall expire at the end of the Initial
Term.

     3.4 Term. All references to the "Term" in this Lease shall include the
Initial Term set forth in Paragraph 3.1 plus any extensions pursuant to
Paragraph 3.3.

     3.5 Fair Market Lease Rate. Lessor shall give Lessee notice ("Lessor's
Notice") of the fair market lease rate after receiving Lessee's written notice
of intent to exercise the Option, provided that Lessor's Notice shall not be
delivered later than 120 days prior to the commencement of the Option Term. If
Lessee believes that the fair market lease rate as established by Lessor is
incorrect, Lessee shall notify Lessor in writing within 20 days of Lessee's
receipt of the notice from Lessor that Lessee desires to submit the matter to
appraisal with a designation of an MAI qualified appraiser. If Lessor agrees
with the identity of such appraiser, it shall within 10 days notify the
appraiser and Lessee that such appraiser shall determine the fair market lease
rate (including fair market increases during the Option Term). If not, Lessor
shall submit the name of its appraiser to Lessee within said 10 days. The two
appraisers so selected shall choose a third appraiser and the three together
shall determine the fair market lease rate (including fair market increases
during the Option Term). If the two appraisers cannot select a third

                                       -2-



<PAGE>
appraiser within 20 days after Lessor submits the name of its appraiser, either
party may at any time apply to the presiding judge of any court of competent
jurisdiction for the appointment of the third appraiser. If the three appraisers
are unable to agree on the fair market lease rate they shall each determine the
fair market lease rate assuming annual CPI increases during the Option Term and
then average their determinations by tossing out the high and low appraisal and
accepting the middle appraisal as the fair market lease rate. The costs of the
appraisal process shall be borne by Lessee unless the fair market lease rate as
determined by the appraisal is more than 10% below the lease rate set forth in
Lessor's Notice in which case Lessor and Lessee shall share the costs of the
appraisal process equally. The appraisal process shall be completed as quickly
as reasonably possible. If for any reason the Option Term commences prior to the
conclusion of the appraisal process, Lessee shall continue to pay the monthly
base rent then in effect to Lessor plus 10% of such amount, which 10% only shall
be held by Lessor in escrow pending completion of the appraisal process, at
which time all funds held in escrow shall be distributed to Lessee and/or Lessor
in accordance with the outcome of the appraisal process, and Lessee shall
subsequently be bound by the lease rate as determined by the appraisal process.
The rent during the Option Term shall continue to be adjusted as agreed upon
between Lessor and Lessee or as determined by the appraisal process.

     4.0 RENT

     4.1 Monthly Rent. Lessee shall pay to Lessor as rent for the Premises in
advance on the first day of each calendar month of the Term without deduction,
offset, prior notice or demand, in lawful money of the United States, the sum
specified in Paragraph 1.3 above which is based $.92 per square foot on the
square footage set forth in Paragraph 2.0. The rent owing shall be adjusted as
necessary if the actual square footage is shown to be other than as set forth in
Paragraph 2.0.

     4.2 Rent Adjustment. For the period through April 30, 1998 the base rent
set forth in Paragraph 4.1 above shall be adjusted as follows. On October 1,
1990 and every three years thereafter (the "Adjustment Dates"), by the
percentage increase in the Consumer Price Index (all items) for all urban
consumers in the San Francisco-Oakland metropolitan area, published by the
United States Department of Labor, Bureau of Labor Statistics. The monthly rent
until the next Adjustment Date shall be the greater of (a) the rent in effect
immediately before the Adjustment Date or (b) the initial rent set forth in
Paragraph 4.1 above multiplied by a fraction, the numerator of which shall be
said Index number for the calendar month three months prior to the Adjustment
Date and the denominator of which shall be said Index number for the calendar
month three months prior to the first full calendar month following the
Commencement Date. Notwithstanding the above, in no case shall the increase as
of any Adjustment Date exceed 21% plus the Carry Forward. As used above, the
"Carry Forward" shall mean the percentage increases in CPI which are not used at
earlier Adjustment Dates to adjust the rent because of this limitation. For
example, if the CPI increase is 15% on October

                                       -3-


<PAGE>


1, 1990, then the Carry Forward is six percent and the CPI increase on October
1, 1993 shall be the actual CPI increase, not to exceed 27%. If the actual CPI
increase on October 1, 1993 were 23%, then the Carry Forward to October 1, 1996
would be four percent. Should the Bureau discontinue the publication of said
Index numbers, or publish the same less frequently, or alter the same in some
other manner, then Lessor shall adopt a substitute index or procedure which
reasonably reflects consumer prices. Commencing May 1, 1998, the adjustment
mechanism set forth above shall be discarded and rent shall be adjusted to 95%
of the fair market lease rate as of May 1, 1998 for comparable space in the
Berkeley area, provided that in no event shall the new rental rate be less than
the rental rate in effect immediately before such adjustment. (Adjustments
subsequent to May 1, 1998 shall be determined in the course of establishing the
fair market lease rate.) On or before January 1, 1998, Lessor shall provide
Lessee with notice of the May 1, 1998 fair market lease rate. The fair market
lease rate shall then be determined in accordance with Paragraph 3.5, and the
notice referenced above shall be deemed "Lessor's Notice."

     4.3 Mode Of Payment. Lessee shall pay all rent due Lessor at Lessor's
address set forth on the signature page hereof, or any such other place as
Lessor may designate from time to time in writing.

     4.4 Triple Net Lease. This Lease is what is commonly called a "Net, Net,
Net Lease," it being understood that Lessor shall receive the rent set forth
herein free and clear of any and all other impositions, taxes, liens, charges or
expenses of any nature whatsoever in connection with the ownership and operation
of the Premises. In the event of non-payment of all or any portion of such
charges, costs and expenses, Lessor shall have the same rights and remedies as
provided in this Lease for failure of Lessee to pay rent. Lessee shall in no
event be entitled to any abatement or reduction of rent or other monetary sums
payable hereunder, except as expressly provided herein, notwithstanding any
present or future law to the contrary.

     4.5 Estimated Payments. Lessee shall be notified by Lessor of Estimated
Payments for taxes, insurance, maintenance of the landscaping and parking lot,
and landscaping and parking lot utilities and services from time to time. The
Estimated Payments shall be paid by Lessee together with rent, on the first day
of each month throughout the Term. The Estimated Payments may be increased or
decreased by Lessor upon 30 days' written notice to Lessee based upon statements
received or charges incurred by Lessor, information available to Lessor as to
the probable cost of expected charges and expenses, or the reasonable estimate
of Lessor as to the probable amount of expected charges or expenses. Lessor
shall be entitled to retain the monies received from such payments in its
general fund pending payment of all such costs and charges. No more frequently
than once each calendar quarter, the actual costs shall be determined by Lessor,
and Lessee shall remit to Lessor on demand its unpaid pro rata share of the
actual expense. In the event Lessee paid more than the actual expenses for such
period of time, Lessor shall apply such overpayment towards the next Estimated
Payments owing by Lessee. At the termination of

                                      - 4 -


<PAGE>


this Lease, an accounting for such charges and expenses shall be made to the
nearest practical accounting period, and Lessee shall pay to Lessor any balance
due, or the Lessor shall refund to Lessee any excess amount paid.

     4.6 Security Deposit. Lessee has deposited with Lessor as a security
deposit the sum specified in Paragraph 1.4 above (the "Deposit"). On May 1, 1998
and May 1, 2003 (unless the Lease is terminated or the Option is not exercised,
as the case may be) Lessee shall increase the Deposit to that amount which is
equal to the newly established monthly rental. The Deposit shall be held by
Lessor as a security deposit for the faithful performance by Lessee of all
terms, covenants, and conditions of this Lease to be kept and performed by
Lessee during the Term. If Lessee defaults with respect to any provisions of
this Lease, including but not limited to the provisions relating to the payment
of rent and any of the monetary sums due hereunder, Lessor may (but shall not be
required to) use, apply or retain any part or all of the Deposit for the payment
of any amount which Lessor may spend or become obligated to spend by reason of
Lessee's default or to compensate Lessor for any loss or damage which Lessor may
suffer by reason of Lessee's default. If any portion of the Deposit is so used
or applied, Lessee shall, within 10 days after written demand therefor, deposit
cash with Lessor in an amount sufficient to restore the Deposit to its original
amount; Lessee's failure to do so shall be a material breach of this Lease.
Lessor shall not be required to keep the Deposit separate from its general
funds, and Lessee shall not be entitled to interest on the Deposit. If Lessee
shall fully and faithfully perform every provision of this Lease to be performed
by it, the Deposit or any balance thereof shall be returned to Lessee (or, at
Lessor's option, to the last assignee of Lessee's interests hereunder) at the
expiration of the Term and after Lessee has vacated the Premises. In the event
of termination of Lessor's interest in this Lease, Lessor shall transfer the
Deposit to Lessor's successor in interest, whereupon Lessee agrees to release
Lessor from all liability for the return of the Deposit or the accounting
therefor.

     4.7 Late Charges. Lessee hereby acknowledges that late payment by Lessee to
Lessor of rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this Lease, the exact amount of which will be extremely
difficult to ascertain. Such costs include, but are not limited to, processing
and accounting charges, and late charges which may be imposed on the Lessor by
the terms of any mortgage or trust deed covering the Premises. Accordingly, if
any installment of rent or any other sum due from Lessee shall not be received
by Lessor or Lessor's designee within 10 days after such amount shall be due,
Lessee shall pay to Lessor a late charge equal to five percent of such overdue
amount. The parties hereby agree that such late charge represents a fair and
reasonable estimate of the costs Lessor will incur by reason of late payment by
Lessee. Acceptance of such late charge by Lessor shall in no event constitute a
waiver of Lessee's default with respect to such overdue amount, nor prevent a
Lessor from exercising any of the other rights and remedies granted hereunder.

                                       -5-


<PAGE>


     5.0 TAXES.

     5.1 Real Property Taxes. Lessee agrees to pay to Lessor in addition to the
rent and other charges herein all Real Property Taxes in accordance with
Paragraph 4.5. As used herein, "Real Property Taxes" shall include any form of
assessment, license, fee, rent, tax, levy, penalty or tax imposed by any
authority having the direct or indirect power to tax, including any improvement
district, as against any legal or equitable interest of Lessor in the Premises
or as against Lessor's business of renting the Premises. Lessee's share of Real
Property Taxes shall be equitably prorated to cover only the period of time
within the fiscal tax year during which this Lease is in effect. With respect to
any assessments which may be levied against or upon the Premises, and which may
be paid in annual installments, only the amount of such annual installments
(with appropriate proration for any partial year) and interest due thereon shall
be included within the computation of the annual Real Property Taxes. Lessor
represents that, to the best of his knowledge, there are no assessment or
improvement districts being planned which would affect the Premises other than
as in effect as of the date of this Lease.

     5.2 Personal Property Taxes. Lessee shall pay before delinquency all taxes
levied or assessed on Lessee's fixtures, improvements, furnishings, merchandise,
equipment and personal property in and on the Premises, whether or not affixed
to the real property. If Lessee in good faith contests the validity of any such
personal property taxes, then Lessee shall at its sole expense defend itself and
Lessor against the same and shall pay and satisfy any adverse determination or
judgment that may be rendered thereon and shall furnish Lessor with a surety
bond satisfactory to Lessor in an amount equal to 150% of such contested taxes.
Lessee shall indemnify Lessor against liability for any such taxes and/or any
liens placed on the Premises in connection with such taxes. If at any time after
any tax or assessment has become due or payable Lessee or its legal
representative neglects to pay such tax or assessment, Lessor shall be entitled,
but not obligated, to pay the same at any time thereafter and such amount so
paid by Lessor shall be repaid by Lessee to Lessor with Lessee's next rent
installment together with interest at the highest rate allowable by law.

     6.0 INSURANCE.

     6.1 Property/Rental Insurance - Premises. During the Term, Lessor shall
keep the Premises insured against loss or damage by fire and those risks
normally included in the term "all risk" including (a) flood coverage at the
election of Lessor, (b) earthquake coverage at the reasonable election of
Lessor, (c) coverage for loss of rents and (d) boiler and machinery coverage if
the Lessor deems necessary. Any deductibles shall be paid by Lessee if the
deductible arises from damage solely to the Premises. The amount of such
insurance shall be not less than l00% of the replacement value of the Premises.
Any recovery received from said insurance policy shall be paid to Lessor.
Lessee, in addition to the rent and other charges provided herein, agrees to pay
to Lessor

                                       -6-


<PAGE>


the premiums for all such insurance. The insurance premiums shall be paid in
accordance with Paragraph 4.5. Lessee shall pay to Lessor any deductibles owing
within 15 days after receipt of notice from Lessor of the amount owing.

     6.2 Property Insurance - Fixtures And Inventory. During the Term, Lessee
shall, at its sole expense, maintain insurance with "all risk" coverage on any
fixtures, leasehold improvements, furnishings, merchandise, equipment or
personal property in or on the Premises, whether in place as of the date hereof
or installed hereafter, for the full replacement value thereof, and Lessee shall
also have sole responsibility and cost for maintaining any other types of
insurance relating to Lessor's use of the Premises. Any deductibles shall be
paid by Lessee.

     6.3 Lessor's Liability Insurance. During the Term, Lessor shall maintain a
policy or policies of comprehensive general liability insurance insuring Lessor
(and such others as designated by Lessor) against liability for bodily injury,
death and property damage on or about the Premises, with combined single limit
coverage of not less than $2,000,000.

     6.4 Lessee's Liability Insurance. During the Term, Lessee shall, at its
sole expense, maintain for the mutual benefit of Lessor and Lessee,
comprehensive general liability and property damage insurance against claims for
bodily injury, death or property damage occurring in or about the Premises or
arising out of the use or occupancy of the Premises, with combined single limit
coverage of not less than $2,000,000. The limits of such insurance shall not
limit the liability of Lessee. Lessee shall furnish to Lessor prior to the
Commencement Date, and at least 30 days prior to the expiration date of any
policy, certificates indicating that the liability insurance required by Lessee
above is in full force and effect, that Lessor has been named as an additional
insured; and that all such policies will not be cancelled unless 30 days' prior
written notice of the proposed cancellation has been given to Lessor. The
insurance shall be with insurers reasonably approved by Lessor and with policies
in form reasonably satisfactory to Lessor. Said policies shall provide that
Lessor, although an additional insured, may recover for any loss suffered by
Lessor by reason of Lessee's negligence, and shall include a broadform liability
endorsement.

     6.5 Waiver Of Subrogation. Lessor hereby releases Lessee, and Lessee hereby
releases Lessor, and their respective officers, agents, employees and servants,
from any and all claims or demands of damages, loss, expense or injury to the
Premises, or to the furnishings and fixtures and equipment, or inventory or
other property of either Lessor or Lessee in, about or upon the Premises, which
is caused by or results from perils, events or happenings which are the subject
of insurance carried by the respective parties and in force at the time of any
such loss; provided, however, that such waiver shall be effective only to the
extent permitted by the insurance covering such loss and to the extent such
insurance is not prejudiced thereby. Each party shall cause each insurance
policy obtained by it to provide that the insurance company waives all right of
recovery by way of subrogation against

                                       -7-


<PAGE>


either party in connection with any damage covered by any policy.

     6.6 Indemnification. Except to the extent of intentional misconduct by
Lessor or Lessor's negligence, Lessee will indemnify Lessor and save it harmless
from and against any and all claims, actions, damages, liability and expense in
connection with loss of life, personal injury and/or damage to property arising
from or out of any occurrence in, upon or at the Premises, or the occupancy or
use by Lessee of the Premises or any part thereof, or occasioned wholly or in
part by any acts or omissions of Lessee, its agents, contractors, employees,
servants, licensees or concessionaires or by anyone permitted to be on the
Premises by Lessee. In case Lessor shall be made a party to any such litigation
commenced by or against Lessee, then Lessee shall protect and hold Lessor
harmless from all claims, liabilities, costs and expenses, and shall pay all
costs, expenses and reasonable legal fees incurred by Lessor in connection with
such litigation.

     6.7 Plate Glass Replacement. Lessee shall replace at its sole expense, any
and all plate glass and other glass in and about the Premises which is damaged
or broken by vandalism. If any plate glass or other glass in and about the
Premises is damaged or broken by causes other than vandalism then Lessee shall
pay Lessor an amount equal to Lessor's cost of replacement, provided that such
amount shall not exceed the deductible then in effect on Lessor's insurance
policy, if any, covering the damaged glass. Nothing herein shall be construed to
require Lessor to carry plate glass insurance.

     6.8 Workers' Compensation Insurance. Lessee shall, at its sole expense,
maintain and keep in force during the Term a policy or policies of Workers'
Compensation Insurance and any other employee benefit insurance sufficient to
comply with all applicable laws, statutes, ordinances and governmental rules,
regulations or requirements.

     7.0 MAINTENANCE.

     7.1 Premises. Throughout the Term, Lessee agrees to keep and maintain all
improvements and appurtenances upon the Premises, including all sewer
connections, plumbing, heating and cooling appliances, wiring and glass, in good
order and repair including the replacement of such improvements and
appurtenances when necessary. Lessee hereby expressly waives the provisions of
any law permitting repairs by a tenant at the expense of a landlord, including,
without limitation, all rights of Lessee under Sections 1941 and 1942 of the
California Civil Code. Lessee agrees to keep the Premises clean and in sanitary
condition as required by the health, sanitary and police ordinances and
regulations of any political subdivision having jurisdiction. Lessee further
agrees to keep the interior of the Premises, such as the windows, floors, walls
doors, showcases and fixtures clean and neat in appearance and to remove all
trash and debris which may be found in or around the Premises. If Lessor deems
any repairs and/or maintenance to be made by Lessee necessary and Lessee refuses
or neglects to commence such repairs and/or maintenance and complete the same
with reasonable dispatch upon demand, Lessor may enter the

                                      - 8 -


<PAGE>


Premises and cause such repairs and/or maintenance to be made and shall not be
responsible to Lessee for any loss or damage occasioned thereby except to the
extent that Lessee's personal property is damaged by the intentional misconduct
or negligence of Lessor or its contractors. Lessee agrees that upon demand, it
shall pay to Lessor the cost of any such repairs, together with accrued interest
from the date of payment at the highest rate allowable by law.

     7.2 Building. Lessor shall maintain the foundation, roof and exterior walls
(the "Structural Components") of the Premises in reasonably good order and
repair, except that damage occasioned by the act of Lessee shall be repaired by
Lessor at Lessee's expense. Lessee shall have the obligation to notify Lessor,
in writing, of any repairs or maintenance to the Structural Components which may
be required, and Lessor shall have a reasonable time to make such repairs. The
manner and method of maintenance and repair of the Structural Components shall
be at the reasonable discretion of Lessor.

     7.3 Maintenance - Landscaping, Parking Lot. Lessor shall maintain the
landscaping and parking lot in reasonable good order and condition, except that
damage occasioned by the act of Lessee shall be repaired by Lessor at Lessee's
expense. Lessee shall have the obligation to notify Lessor, in writing of any
repairs or maintenance to the landscaping and parking lot which may be required,
and Lessor shall have a reasonable time to make such repairs. The manner and
method of maintenance and repair shall be at the reasonable discretion of
Lessor. Lessee, in addition to the rent and other charges provided herein agrees
to pay to Lessor the costs of maintaining the landscaping and parking lot in
accordance with Paragraph 4.5

     7.4 Alterations, Changes And Additions By Lessee. No changes, alterations,
or additions shall be made by Lessee to the Premises without the prior written
consent of Lessor which Lessor will not unreasonably withhold. Notwithstanding
the above, non-structural changes aggregating no more than $10,000 in any 12
month period may be made by Lessee without Lessor's consent. As used herein,
alterations include utility installations such as dusting, power panels,
fluorescent fixtures, base heaters, conduit and wiring. As a condition to giving
such consent, Lessor may require that Lessee agree to remove any such
alterations, additions or improvements at the expiration of the Term and to
restore the Premises to their prior condition. As a further condition to giving
such consent, Lessor may require Lessee to provide Lessor, at Lessee's sole cost
and expense, with a lien and completion bond in an amount equal to one and
one-half times the estimated cost of such improvements, to insure Lessor against
any liability for mechanics' and materialmen's liens and to insure completion of
the work. All changes, alterations or additions to be made to the Premises shall
be under the supervision of a competent architect or competent licensed
structural engineer and made in accordance with plans and specifications which
have been furnished to and approved by Lessor prior to commencement of

                                       -9-


<PAGE>


work. Lessor shall not unreasonably withhold its approval of such proposed
alterations. If the written consent of Lessor to any proposed alterations by
Lessee shall have been obtained, Lessee agrees to advise Lessor in writing of
the date upon which such alterations will commence in order to permit Lessor to
post a notice of nonresponsibility. All such alterations, changes and additions
shall be constructed in a good and workmanlike manner in accordance with all
ordinances and laws relating thereto. Any such changes, alterations or additions
to or on the Premises shall remain for the benefit of and become the property of
Lessor, unless Lessor requires the removal by giving Lessee written notice
within 30 days before the date Lessee is to vacate the Premises, in which case
Lessee shall remove such changes, alterations and additions and restore the
Premises to the condition they were in prior to such changes, alterations or
additions.

     7.5 Plumbing. Lessee shall not use the plumbing facilities for any purpose
other than that for which they were constructed. The expense of any breakage,
stoppage or other damage relating to the plumbing and resulting from the
introduction by Lessee, its agents, employees or invitees of foreign substances
into the plumbing facilities shall be borne by Lessee.

     7.6 Liens. Lessee shall keep the Premises free from any liens arising out
of work performed, materials furnished or obligations incurred by Lessee and
shall indemnify, hold harmless and defend Lessor from any liens and encumbrances
arising out of any work performed or materials furnished by or at the direction
of Lessee. In the event that Lessee shall not, within 20 days following the
imposition of any such lien, cause such lien to be released of record by payment
or posting of a proper bond, Lessor shall have, in addition to all other
remedies provided herein and by law, the right, but not the obligation, to cause
the same to be released by such means as it shall deem proper, including payment
of the claim giving rise to such lien. All such sums paid by Lessor and all
expenses incurred by it in connection therewith including attorneys' fees and
costs shall be payable to Lessor by Lessee on demand with interest at the
highest rate allowable by law. Lessor shall have the right at all times to post
and keep posted on the Premises any notices permitted or required by law, or
which Lessor shall deem proper, for the protection of Lessor and the Premises,
and any other party having an interest therein, from mechanics' and
materialmen's liens, and Lessee shall give to Lessor at least 10 business days'
prior written notice of the expected date of commencement of any work relating
to alterations or additions to the Premises.

     8.0 MANAGEMENT.

     Lessee shall bear all costs to Lessor of managing the Premises and real
property. Lessee understands that Wareham Property Group, or another affiliated
or unaffiliated third party will be responsible for the management of the
Premises. For the period through April 30, 1998, Lessee shall pay to Lessor a
property management fee equal to two and one-half percent of the monthly rent.
Thereafter, the monthly property management fee payable by Lessee shall be equal
to the monthly property

                                     - 10 -


<PAGE>


management fee owing by Lessee immediately prior to May 1, 1998, subject to
adjustment as follows. Commencing May 1, 1998 and each anniversary thereafter,
the monthly property management fee shall be adjusted upwards by increases in
the CPI between the Adjustment Date and the same date one year earlier. The
monthly property management fee shall be payable with monthly rent.

     9.0 UTILITIES AND SERVICES.

     Lessee shall pay prior to delinquency throughout the Term the cost of
water, gas, heating, cooling, sewer, telephone, electricity, garbage, air
conditioning and ventilating, janitorial services, landscaping and all other
materials and utilities supplied to the Premises and real property, provided
that if payment is to be made to Lessor, it shall be made by Lessee within 30
days of receipt of the statement for such charges.

     10.0 USE OF PREMISES.

     10.1 Use. The Premises shall be used and occupied by Lessee for only the
purposes specified in Paragraph 1.5 and for no other purposes whatsoever without
obtaining the prior written consent of Lessor which shall not be unreasonably
withheld.

     10.2 Suitability. This Lease shall be subject to all applicable zoning
ordinances and to any municipal, county and state laws and regulations governing
and regulating the use of the Premises. Lessee acknowledges that neither Lessor
nor Lessor's agent has made any representation or warranty as to the suitability
of the Premises for the conduct of Lessee's business.

     10.3 Uses Prohibited.

     a. Rate Of Insurance. Lessee shall not do or permit anything to be done in
or about the Premises which will cause the existing rate of insurance upon the
Premises (unless Lessee shall pay an increased premium as a result of such use
or acts) or cause the cancellation of any insurance policy covering said
Premises or any building of which the Premises may be a part, nor shall Lessee
sell or permit to be kept, used or sold in or about such Premises any articles
which may be prohibited by a standard form policy of fire insurance.

     b. Interfere With Other Tenants. Lessee shall not allow the Premises to be
used for any unlawful or objectionable purpose, nor shall Lessee cause, maintain
or permit any nuisance in, or about the Premises. Lessee shall not commit or
suffer to be committed any waste in or upon the Premises.

     c. Applicable Laws. Lessee shall not use the Premises or permit anything to
be done in or about the Premises which will in any way conflict with any law,
statute, zoning restriction, ordinance, governmental rule, regulation or
requirements of duly constituted public authorities whether now in force or
which may hereafter be enacted or promulgated.

                                      -11-


<PAGE>


Lessee shall at its sole cost and expense properly comply with all laws,
statutes, ordinances and governmental rules, regulations or requirements now in
force or which may hereafter be in force and with the requirements of any board
of fire underwriters or other similar body now or hereafter constituted relating
to or effecting the condition, use or occupancy of the Premises. The judgment of
any court of competent jurisdiction or the admission of Lessee in any action
against Lessee, whether Lessor be a party thereto or not, that Lessee has
violated any law, statute, ordinance or government rule, regulation or
requirement, shall be conclusive of that fact as between Lessor and Lessee.

     d. Signs. Lessee shall not place any sign upon the Premises or conduct any
auction thereon without Lessor's prior written consent.

     10.4 Lessee's Warranty. Lessee warrants that its use of the Premises
presently complies and shall comply with applicable federal, state and local
laws and regulations pertaining to (i) the use, storage and disposal of
radiological materials and/or toxic chemicals, (ii) the disposal of hazardous
waste and (iii) the safety of persons on the Premises, including but not limited
to, the general industry safety orders as set forth in Title 8 of the California
Administrative Code. Lessee further warrants that it will not interfere with any
actions by Lessor made in furtherance of the above laws and regulations and it
shall comply with any reasonable procedures and/or regulations promulgated by
Lessor from time to time in connection with the matters covered by such laws and
regulations, provided that Lessor shall have no duty to establish any procedures
or regulations or to supervise in any way Lessee's activities on the Premises.
Lessee warrants that all governmental inspections of the Premises as required
under the laws referenced above have been made and will be made, and Lessee
shall deliver within 15 days of the date hereof to Lessor a copy of the reports
of each such inspection most recently conducted. Lessee shall provide a copy of
the reports for each such future inspection within 15 days of Lessee's receipt
of such report. Except in instances when a governmental report of such
inspection has been made within the last 12 month period, Lessee shall obtain at
its sole cost an inspection by a private engineering firm, resulting in a
written report specifying Lessee's compliance, or enumerating the reasons for
Lessee's lack of compliance, with such regulations. Lessee indemnifies and shall
hold Lessor harmless from a breach of the above warranty and from any claim
arising from Lessee's particular use of the Premises, including but not limited
to, (a) the disposal or use of hazardous waste, or (b) the disposal or escape of
odorous, carcinogenic and/or pathogenic exhaust from the Premises. Lessee shall
pay all of Lessor's costs and reasonable attorneys' fees arising from a breach
of Lessee's warranty set forth above, whether or not litigation is commenced,
including but not limited to, the costs of defending any claims made against
Lessor as a result of such breach. Lessor shall have the right to defend such
claims with attorneys of its own election and Lessee shall pay the cost thereof.
Nothing herein shall suggest that Lessee shall be responsible for the condition
of the Premises prior to its first obtaining possession of the Premises.

                                     - 12 -


<PAGE>


     11.0 DEFAULT PROVISIONS.

     11.1 Insolvency. If, during the Term, Lessee shall be declared insolvent or
bankrupt, or if any assignment of Lessee's property shall be made for the
benefit of creditors or otherwise, or if Lessee's leasehold interest herein
shall be levied upon under execution or seized by virtue of any writ of any
court of law, or a trustee in bankruptcy or a receiver be appointed for the
property of Lessee, any such occurrence shall be a material default of this
Lease, and entitle Lessor at its election to terminate the Lease.

     11.2 Non-Payment, Breach Or Vacating. If (a) Lessee shall fail to make
payment of any rent or any charge owing hereunder, or (b) any other covenant,
condition, agreement or obligation of Lessee hereunder is not timely performed
and either the breach is not cured within 15 days after written notice from
Lessor or the cure of the breach is not commenced within 15 days after written
notice from Lessor and thereafter diligently prosecuted towards completion,
Lessee shall be in default and Lessor shall be entitled to take the actions set
forth in Paragraphs 11.4 and 11.5 below and Lessor may pursue any other remedy
available by law.

     11.3 Default Under Other Leases. Any default under either the Building E
Lease or the Building C Lease shall be deemed a default under this Lease,
entitling Lessor to take the actions set forth in Paragraphs 11.4 and 11.5 below
and Lessor may pursue any other remedy available by law.

     11.4 Lessor's Right To Relet. Upon recovery of possession of the Premises,
whether with or without legal proceedings, by reason of Lessee's breach of this
Lease, Lessor may, at its option, at any time and from time to time, remove any
signs and property of Lessee therefrom and relet the Premises or any part
thereof at such rent and upon such terms and conditions as Lessor in its
discretion shall determine, and the term of such reletting may be for a term
extending beyond the Term. Such reletting shall neither void nor terminate this
Lease. For the purpose of such reletting, Lessor is authorized to make repairs
or alterations in or to the Premises at the sole expense of Lessee as may be
necessary or desirable for the purpose of such reletting. The costs and expenses
of such reletting, including repairs and alterations and any reasonable real
estate commissions associated with such reletting shall be paid by Lessee. If a
sum shall not be realized from such reletting to equal the monthly rent payable
hereunder plus all other monthly charges to be paid by Lessee hereunder, less
any amount of rental loss for the same period which Lessee proves could be
reasonably avoided by Lessor, Lessee will pay such deficiency each month to
Lessor. In no event shall Lessor be entitled to any excess rent received by
Lessor. No re-entry, taking of possession or reletting of the Premises by Lessor
shall be construed as an election to terminate this Lease unless written notice
of such intention is given to Lessee or unless terminated thereof is decreed by
a court of competent jurisdiction.

                                      -13-


<PAGE>


     11.5 Right To Terminate. Notwithstanding any such reletting without
termination, Lessor may at any time during the Term elect to terminate the Lease
by reason of a previous breach. In the event that Lessor shall at any time
terminate this Lease by reason of breach thereof by Lessee, then Lessor, in
addition to any other remedy it may have, may recover from Lessee any damages
incurred by reason of such breach including, without limitation, the cost of
recovering the Premises, and the amount by which the rent then unpaid for the
balance of the Term exceeds the amount of such rental loss for the same period
which the Lessee proves could be reasonably avoided by Lessor. Lessee hereby
waives all statutory rights inconsistent with this Paragraph.

     11.6 Default By Lessor. Lessor will be in default if Lessor fails to
perform any obligation required of Lessor within 30 days after written notice by
Lessee, specifying wherein Lessor has failed to perform such obligation;
provided that if the nature of Lessor's obligation is such that more than 30
days are required for performance, then Lessor shall not be in default if Lessor
commences performance within such 30 day period and thereafter diligently
prosecutes the same to completion; and provided further that if the performance
of any obligation required by Lessor is necessary to correct a condition that
poses a threat to life or property, then Lessor shall perform such obligation as
soon as reasonably possible after receiving written notice from Lessee,
specifying that the condition is threatening.

     12.0 EXPIRATION OR TERMINATION.

     12.1 Surrender Of Possession. Lessee agrees to deliver up and surrender to
Lessor possession of the Premises and all improvements thereon, subject to the
terms of Paragraph 7.4 above, in as good order and condition as when possession
was taken by Lessee, excepting only ordinary wear and tear. Upon termination of
this Lease, Lessor may reenter the Premises and remove all persons and property
therefrom. If Lessee shall fail to remove any effects which it is entitled to
remove from the Premises upon the termination of this Lease, for any cause
whatsoever, Lessor, at its option, may remove the same and store or dispose of
them, and Lessee agrees to pay to Lessor on demand any and all expenses incurred
in such removal and in making the Premises free from all dirt, litter, debris
and obstruction, including all storage and insurance charges. If the Premises
are not surrendered at the end of the Term, Lessee shall indemnify Lessor
against loss or liability resulting from delay by Lessee in so surrendering the
Premises, including, without limitation, any claims made by any succeeding
Lessee founded on such delay.

     12.2 Holding Over. If Lessee, with Lessor's consent, remains in possession
of the Premises after expiration of the term and if Lessor and Lessee have not
executed an express written agreement as to such holding over, then such
occupancy shall be a tenancy from month to month at a monthly rental equivalent
to 110% of the monthly rental in effect immediately prior to such expiration,
such payments to be made as herein provided. In the event of such holding over
all of the terms of this Lease including the payment of all charges owing

                                      -14-


<PAGE>


hereunder other than rent shall remain in force and effect on said month to
month basis.

     12.3 Voluntary Surrender. The voluntary or other surrender of this Lease by
Lessee, or a mutual cancellation thereof, shall not work a merger, but shall, at
the option of Lessor, terminate all or any existing subleases or subtenancies,
or operate as an assignment to Lessor of any or all such subleases or
subtenancies.

     13.0 CONDEMNATION OF PREMISES.

     13.1 Total Condemnation. If the entire Premises, whether by exercise of
governmental power or the sale or transfer by Lessor to any condemnor under
threat of condemnation or while proceedings for condemnation are pending, at any
time during the Term, shall be taken by condemnation such that there does not
remain a portion suitable for occupation, this Lease shall then terminate as of
the date transfer of possession is required. Upon such condemnation, all rent
shall be paid up to the date transfer of possession is required, and Lessee
shall have no claim against Lessor for the value of the unexpired term of this
Lease.

     13.2 Partial Condemnation. If any portion of the Premises is taken by
condemnation during the Term, whether by exercise of governmental power or the
sale or transfer by Lessor to any condemnor under threat of condemnation or
while proceedings for condemnation are pending, this Lease shall remain in full
force and effect; except that in the event a partial taking leaves the Premises
unfit for normal and proper conduct of the business of Lessee, then Lessee shall
have the right to terminate this Lease effective upon the date transfer of
possession is required. Moreover, Lessor shall have the right to terminate this
Lease effective on the date transfer of possession is required if more than 33%
of the total square footage of the Premises is taken by condemnation. Lessee and
Lessor may elect to exercise their respective rights to terminate this Lease
pursuant to this Paragraph by serving written notice to the other within 30 days
of their receipt of notice of condemnation. All rent shall be paid up to the
date of termination, and Lessee shall have no claim against Lessor for the value
of any unexpired term of this Lease. If this Lease shall not be cancelled, the
rent after such partial taking shall be that percentage of the adjusted base
rent specified herein, equal to the percentage which the square footage of the
untaken part of the Premises, immediately after the taking, bears to the square
footage of the entire Premises immediately before the taking. If Lessee's
continued use of the Premises requires alterations and repairs by reason of a
partial taking, all such alterations and repairs shall be made by Lessee at
Lessee's expense.

     13.3 Award To Lessee. In the event of any condemnation, whether total or
partial, Lessee shall have the right to claim and recover from the condemning
authority such compensation as may be separately awarded or recoverable by
Lessee for loss of business, fixtures or equipment belonging to Lessee
immediately prior to the condemnation. The balance of any condemnation award
shall belong to Lessor and Lessee shall

                                      -15-


<PAGE>


have no further right to recover from Lessor or the condemning authority for any
additional claims arising out of such taking.

     14.0 ENTRY BY LESSOR.

     Lessee shall permit Lessor and its agents to enter the Premises at all
reasonable times for any of the following purposes: to inspect the Premises; to
maintain the building in which the Premises are located; to make such repairs to
the Premises as Lessor is obligated or may elect to make; to make repairs,
alterations or additions to any other portion of the building in which the
Premises are located; to show the Premises and post "To Lease" signs for the
purposes of reletting during the last 90 days of the Term; to show the Premises
as part of a prospective sale by Lessor or to post notices of nonresponsibility.
Notwithstanding the above, except in the case of emergencies, Lessor shall give
at least 24 hours prior written notice before entry to either the laboratories
or other non-office restricted areas. Lessor shall have such right of entry
without any rebate of rent to Lessee for any loss of occupancy or quiet
enjoyment of the Premises thereby occasioned.

     15.0 INDEMNIFICATION.

     Lessee agrees not to hold Lessor liable for any injury or damage, either
proximate or remote, occurring through or caused by any repairs or alterations
to the Premises, except to the extent such injury or damage arises from the
willful misconduct or negligence of Lessor. Lessee agrees that Lessor shall not
be liable for any injury or damage occasioned by defective electric wiring, or
the breaking, bursting, stoppage or leaking of any part of the plumbing, air
conditioning, heating, fire-control sprinkler systems or gas, sewer or steam
pipes, except to the extent such injury or damage arises from the willful
misconduct or negligence of Lessor. Lessee will save and hold harmless Lessor
from all loss, expense, damage or injury to persons or property arising from or
occurring by reason of its occupation or use of the Premises, except to the
extent such losses or injuries are proximately caused by any willful misconduct
or negligence of Lessor. Lessor shall not be liable for any damage to or loss of
property of Lessee or other persons located on the Premises, and Lessee shall
hold Lessor harmless from any claims arising out of damage to the same, except
to the extent such loss or damage is proximately caused by the willful
misconduct or negligence of Lessor.

     16.0 ASSIGNMENT AND SUBLETTING.

     Lessee shall not assign this Lease in whole or in part, or sublet the
Premises or any part thereof, or license the use of all or any portion of the
Premises or business conducted thereon, or encumber or hypothecate this Lease,
without first obtaining the written consent of Lessor, which consent will not be
unreasonably withheld. Lessee shall submit in writing to Lessor: (a) the name
and legal composition of the proposed sublessee; (b) the nature of the proposed
sublessee's business to be carried on in the Premises; (c) the terms and
provisions of the proposed sublease; and (d) such financial and other reasonable
information as Lessor may

                                     - 16 -


<PAGE>


request concerning the proposed sublessee (the "Sublease Notice"). Any
assignment, subletting, licensing, encumbering, or hypothecating of this Lease
without such prior written consent shall, at the option of Lessor, constitute
grounds for termination of this Lease. Lessor's consent to any assignment or
sublease shall not constitute a waiver of the necessity for such consent to any
subsequent assignment or sublease. This prohibition against assignment and
subletting shall be construed to include a prohibition against assignment or
subletting by operation of law. Notwithstanding any assignment or subletting
with Lessor's consent, Lessee shall remain fully liable on this Lease and shall
not be released from its obligations hereunder. In the event Lessor shall
consent to a sublease or assignment under this Paragraph, Lessee shall pay
Lessor's reasonable attorneys' fees incurred in connection with giving such
consent. In addition, Lessee shall pay to Lessor with its regularly scheduled
rent payments, 75% of all sums collected by Lessee from a sublessee or assignee
which are in excess of the rent and charges then owing to Lessor pursuant to
this Lease.

     17.0 DAMAGE OR DESTRUCTION.

     17.1 Right To Terminate On Destruction Of Premises. Lessor shall have the
right to terminate this Lease if, during the Term, the Premises are damaged to
an extent exceeding 33% of the then reconstruction cost of the Premises as a
whole, or the building as a whole, as the case may be. Lessor shall also have
the right to terminate this Lease if any portion of the Premises is damaged by
an uninsured peril. In either case, Lessor may elect to so terminate by written
notice to Lessee delivered within 30 days of the happening of such damage.

     17.2 Repairs By Lessor. If Lessor shall not elect to terminate this Lease
pursuant to Paragraph 17.1, Lessor shall, immediately upon receipt of insurance
proceeds paid in connection with such casualty, but in no event later than 90
days after such damage has occurred, proceed to repair or rebuild the Premises,
on the same plan and design as existed immediately before such damage or
destruction occurred, subject to such delays as may be reasonably attributable
to governmental restrictions or failure to obtain materials or labor, or other
causes beyond the control of Lessor. Lessee shall be liable for the repair and
replacement of all fixtures, leasehold improvements, furnishings, merchandise,
equipment and personal property not covered by the property insurance described
in Paragraph 6.2.

     17.3 Reduction Of Rent During Repairs. In the event Lessee is able to
continue to conduct its business during the making of repairs, the rent then
prevailing will be equitably reduced in the proportion that the unusable part of
the Premises bears to the whole thereof for the period that repairs are being
made. No rent shall be payable while the Premises are wholly unusable due to
casualty damage.

     17.4 Arbitration. Any controversy or claim arising out of or relating to
this Paragraph shall be settled by arbitration in accordance with the rules of
the American Arbitration Association as then in effect, and judgment upon

                                      -17-


<PAGE>


the award rendered by the arbitration may be entered in any court having
jurisdiction. The expenses of arbitration shall be borne by the parties as
allocated by the arbitrators. The party desiring arbitration shall serve notice
upon the other party, together with designation of the first party's arbitrator.

     17.5 Lessor's Overriding Right To Terminate. Notwithstanding anything to
the contrary herein, if the discounted present value of the rent due hereunder
for the balance of the Term, using as the discount rate the prime commercial
lending rate in effect at the Bank of America as of the date Lessor is to
commence repairs pursuant to Paragraph 17.2 hereof, is less than the cost of
repairing the damage to the Premises, Lessor may at its option terminate this
Lease upon 10 days' written notice.

     18.0 OPTION TO PURCHASE PREMISES.

     Lessor hereby grants to Lessee the option to purchase the Premises in
accordance with the provisions of this Paragraph, as long as Lessee is not in
default under this Lease at the time Lessee exercises its option and at the time
the purchase is closed. Lessee shall have the right to exercise such option to
purchase effective as of May 1, 1998, provided that Lessee has not served notice
upon Lessor of its intent to terminate the Building E Lease pursuant to
Paragraph 3.3 of said Lease. If Lessee does not purchase the Premises as of May
1, 1998, then Lessee shall also have the right to purchase the Premises
effective as of the end of the Initial Term regardless of whether or not Lessee
elects to extend the Term of the Building E Lease pursuant to Paragraph 3.4 of
said Lease. Lessee shall exercise the purchase option by giving Lessor written
notice (the "Purchase Notice") to be received by Lessor at least nine months
prior to May 1, 1998 or the end of the Initial Term, as the case may be. The
purchase price for the Premises shall be the greater of (a) the fair market
value of the Premises at the time of appraisal, plus $340,766, which sum
represents the rent forgiven under the Original Lease or (b) the outstanding
balance of all loans then secured by the Premises. The purchase price shall be
paid fully in cash as of the closing of the sale. Lessor shall give Lessee
written notice ("Lessor's Notice") of the fair market value of the Premises at
least 150 days before May 1, 1998 or the end of the Initial Term, as the case
may be. If Lessee believes that the fair market value as established by Lessor
is incorrect, Lessee shall notify Lessor in writing within 30 days of Lessee's
receipt of the notice from Lessor that Lessee desires to submit the matter to
appraisal with the designation of an MAI qualified appraiser. If Lessor agrees
with the identity of such appraiser, it shall within 30 days notify the
appraiser and Lessee that such appraiser shall determine the fair market value
of the Premises. (If the two appraisers cannot select a third appraiser within
30 days after Lessor submits the name of its appraiser, either side may at any
time apply to the presiding Judge of any court of competent jurisdiction for the
appointment of the third appraiser.) If not, Lessor shall submit the name of its
appraiser to Lessee within said 30 days. The two appraisers so selected shall
choose a third appraiser and the three together shall determine the fair

                                      -18-


<PAGE>


market value of the Premises. If the three appraisers are unable to agree on the
fair market value, they shall each determine the fair market value and then toss
out the high and low appraisals, thereby accepting the middle appraisal as the
fair market value. The cost of the appraisal process shall be borne by Lessee
unless the fair market value as determined by the appraisal is more than 10%
below the fair market value set forth by Lessor in Lessor's Notice in which case
Lessor and Lessee shall share the costs of the appraisal process equally. The
appraisal process shall be completed as quickly as reasonably possible. In
appraising the Premises, the appraisers shall not take into consideration the
existence of this Lease. After the appraisal price has been set, the appraisers
shall immediately notify Lessor and Lessee of the appraisal price. If Lessee
objects to the appraisal price that has been set, Lessee shall have the right to
elect not to purchase the Premises, as long as Lessee pays all costs in
connection with the appraisal procedure. Lessee's election not to purchase the
Premises must be delivered to Lessor within 15 days after receipt of notice from
the appraisers of the appraisal price or Lessor's Notice, as the case may be. If
Lessee does not exercise its election within said period, Lessee shall purchase
the Premises from Lessor as provided in this Paragraph. Lessor shall deliver at
the closing an executed grant deed in recordable form conveying the Premises to
Lessee. Title to the Premises shall be conveyed free and clear of all liens,
encumbrances, covenants, conditions, restrictions, easements and rights of way
of record, leases or other tenancy agreements and other matters of record,
except (a) current taxes, a lien not yet delinquent, (b) those portions of
current assessments not yet due and payable, (c) anything of record or not of
record that in any way affects title to the Premises resulting from the acts or
omissions of Lessee and (d) those matters which are then of record and do not
materially interfere with the use of the Premises. The sale shall be consummated
through an escrow with a title company acceptable to Lessor as escrowholder to
be opened within 20 days after the fair market value of the Premises has been
set, either through appraisal or Lessee's failure to object to the fair market
value established by Lessor's Notice. At the time escrow is opened, Lessee shall
deposit with the title company cash in an amount equal to 10% of the purchase
price, to be used as a nonrefundable deposit towards the purchase price. DUE TO
THE DIFFICULTY OF FIXING THE DAMAGES WHICH WOULD BE SUFFERED BY LESSOR UPON A
FAILURE TO PURCHASE THE PREMISES, IF LESSEE FAILS TO COMPLETE THE PURCHASE OF
THE PREMISES OTHER THAN AS A RESULT OF A DEFAULT BY LESSOR, LESSEE ( ) AND
LESSOR ( ) AGREE BY PLACING THEIR INITIALS ABOVE THAT THE DEPOSIT CONSTITUTES
REASONABLE LIQUIDATED DAMAGES AND THAT LESSOR SHALL RETAIN SUCH DEPOSIT AS
LIQUIDATED DAMAGES. Escrow shall close within 45 days after May 1, 1998 or the
conclusion of the Initial Term, as the case may be. Until close of escrow,
Lessee shall continue to pay the rent and charges owing by Lessee under this
Lease and in effect immediately before the scheduled termination date of this
Lease. At the close of escrow, escrowholder shall issue a CLTA standard coverage
policy of title insurance in the amount of the purchase price insuring title to
the Premises vested in Lessee, subject only to the matters referenced above. The
security deposit previously paid by Lessee to Lessor under

                                     - l9 -


<PAGE>


this Lease will be credited to Lessee in the escrow. The City of Berkeley
transfer tax shall be split equally by the Lessor and Lessee. Lessor shall pay
the County documentary transfer tax. All other closing costs including, but not
limited to, recording fees, escrow fees and title insurance premiums shall be
paid by Lessee.

     19.0 MISCELLANEOUS PROVISIONS.

     19.1 Waiver. No waiver of any breach of any of the covenants or conditions
of this Lease shall be construed to be a waiver of any other breach or to be a
consent to any further or succeeding breach of the same or other covenant or
condition. The subsequent acceptance of rent hereunder by Lessor shall not be
deemed to be a waiver of any preceding breach by Lessee of any term, covenant or
condition of this Lease, other than the failure of Lessee to pay the particular
rent so accepted, regardless of Lessor's knowledge of such preceding breach at
the time of acceptance of such rent.

     19.2 Successors And Assigns. Except as otherwise provided herein, the
provisions hereof shall be binding upon and shall inure to the benefit of the
heirs, personal representatives, successors and assigns of the parties.

     19.3 Notices. All notices, requests, demands and other communications
required or permitted to be given hereunder shall be in writing and either
personally delivered or sent by certified mail, return receipt requested,
postage prepaid, properly addressed to the other party at the address set forth
next to its signature below, or at such other address or addresses as may from
time to time be designated in like manner by one party to the other. Any such
notice shall be deemed given when personally delivered or on the date indicated
on the Post Office's certified mail receipt.

     19.4 Partial Invalidity. If for any reason any provision of this Lease
shall be determined to be invalid or inoperative, the validity and effect of the
other provisions hereof shall not be affected thereby.

     19.5 Number And Gender. All terms in this Lease shall be construed to mean
either the singular or the plural, masculine, feminine or neuter, as the
situation may demand.

     19.6 Descriptive Headings. The headings used herein and in any of the
documents attached hereto as schedules, lists or exhibits are descriptive only
and for the convenience of identifying provisions, and are not determinative of
the meaning or effect of any such provisions.

     19.7 Time Is Of The Essence. In all matters time is of the essence in the
performance of all obligations under this Lease.

     19.8 Entire Agreement. This Lease and the documents attached hereto as
schedules, lists or exhibits, constitute the entire agreement and understanding
between the parties with respect to the subject matters herein and therein, and
supersede and replace any prior agreements and understandings,

                                     - 20 -

<PAGE>


whether oral or written, between and among them with respect to the lease of the
Premises, rental therefor, use thereof and all other such matters. The
provisions of this Lease may be waived, altered, amended or repealed in whole or
in part only upon the written consent of Lessor and Lessee.

     19.9 Memorandum Of Lease. Lessor and Lessee mutually agree that they will
not file or record a copy of this Lease, but that in the event Lessor or Lessee
requests a recording, Lessor and Lessee shall execute and acknowledge a
memorandum of this Lease in a form approved by the parties setting forth in said
memorandum the description of the Premises, the date of the Lease, the
Commencement Date and the date of termination. Said memorandum of Lease may be
recorded in the Recorder's Office of the County in which the Premises are
located.

     19.10 Applicable Law. This Lease Agreement shall be construed and
interpreted in accordance with the laws of the State of California.

     19.11 Corporate Authority. Each individual executing this Lease on behalf
of a corporation represents and warrants that he is duly authorized to execute
and deliver this Lease on behalf of the corporation in accordance with a duly
adopted resolution of the Board of Directors of the corporation, and that this
Lease is binding upon said corporation in accordance with its terms.

     19.12 Litigation Expense. If any party shall bring an action against any
other party hereto by reason of the breach of any covenant, warranty,
representation or condition hereof, or otherwise arising out of this Agreement
or any schedule, list or exhibit hereto, whether for declaratory or other
relief, the prevailing party in such suit shall be entitled to such party's
costs of suit and attorneys' fees, which shall be payable whether or not such
action is prosecuted to judgment.

     19.13 Subordination Of Leasehold. Lessee agrees that this Lease is and
shall be, at all times, subject and subordinate to the lien of any mortgage or
other encumbrances which Lessor may create against the Premises including all
renewals, replacements and extensions thereof; provided, however, that
regardless of any default under any such mortgage or encumbrance or any sale of
the Premises under such mortgage, so long as Lessee performs all covenants and
conditions of this Lease and continues to make all payments hereunder, this
Lease and Lessee's possession and rights hereunder shall not be disturbed by the
mortgagees or anyone claiming under or through such mortgages. Lessee agrees to
execute any and all instruments in writing which may be required by Lessor to
subordinate Lessee's rights to the lien of such mortgage.

     19.14 Lessee's Certificate. Within 15 days following Lessor's request,
Lessee shall complete, execute and deliver to Lessor a Lessee's Certificate,
setting forth the information requested therein including, but not limited to
(a) certification that this Lease is unmodified and in full force and effect (or
if modified, stating the nature of such modification and certifying that this
Lease as so modified is

                                      -21-


<PAGE>


in full force and effect) and the date to which the rental and other charges are
paid in advance, if any, (b) acknowledgement that there are not, to Lessee's
knowledge, any uncured defaults on the part of Lessor hereunder, or specifying
such defaults if any are claimed and (c) setting forth the date of commencement
and expiration of the Term. Failure of Lessee to deliver such Certificate within
said 15 days shall be deemed to be an acknowledgement that Lessor is not in
default under the Lease, and that the terms of the Lease have not been modified
or supplemented in any way. It is intended that such Certificate may be relied
upon by any prospective purchaser, lender or assignee of any lender of the
Premises.

     19.15 Attornment. Lessee shall, in the event of any sale of the Premises or
if proceedings are brought for the foreclosure of, or in the event of exercise
of the power of sale under, any mortgage, installment land contract or deed of
trust made by Lessor covering the Premises, attorn to the mortgagee or the
purchaser upon any such foreclosure or sale and recognize such mortgagee or
purchaser as Lessor under this Lease, provided that Lessee's possession and
rights hereunder shall not be disturbed by the mortgagee or purchaser.

     19.16 Day. As used herein, the term "day" shall mean, unless otherwise
specifically stated, a calendar day.

     19.17 Brokers. The only broker's fees in connection with this Lease shall
be payable by Lessor to Coldwell Banker. Each party hereby indemnifies and
agrees to hold the other harmless from any and all other broker fees.

     IN WITNESS WHEREOF, the parties have executed this Lease on the day and
year first written above. This amended and restated Lease automatically
supersedes the Original Lease as of the Commencement Date without further action
by the parties.


LESSOR:                                LESSEE:


SEVENTH STREET PROPERTIES              XOMA CORPORATION
1120 Nye Street, Suite 400             __________________________
San Rafael, CA 94915                   __________________________
                                               (Address)

By  /s/ Richard K. Robbins             By  /s/ Steven C. Mendell
   --------------------------             -----------------------
    (Signature)                                 (Signature)


   Richard K. Robbins                  Steven C. Mendell/ CEO
- -----------------------------          --------------------------
    (Print Name & Title)              (Print Name & Title)

                                     - 22 -

<PAGE>

                                    EXHIBIT A

                             DESCRIPTION OF PREMISES












                                     - 23 -












                          AMENDMENT TO BUILDING E LEASE

     AMENDMENT made and entered into this 21 day of April, 1988, by and between
SEVENTH STREET PROPERTIES II ("Lessor") and XOMA CORPORATION ("Lessee") to that
certain Triple Net Lease (the "Building E Lease") entered into between Lessor
and Lessee for approximately 35,000 square feet in Building E of Aquatic Park
Center and dated , 1987 as amended by a Letter Agreement between Lessor and
Lessee dated June 26, 1987.

     Lessor and Lessee hereby agree to amend the Building E Lease as follows:

     The definition of "shell condition" as used in the Building E Lease shall
be as defined in Exhibit B of the Building E Lease, except that the following
improvements shall be deleted from the definition of shell condition: (1) fire
sprinklers, (2) landscaping, (3) parking lot and (4) site lighting. The Premises
shall be delivered by Lessor to Lessee without the above four listed
improvements.

     Except as specifically amended above, the Building E Lease shall remain
unmodified and in full force and effect.

     IN WITNESS WHEREOF, the parties have executed this Amendment to the
Building E Lease on the day and year first written above.


LESSOR:                                     LESSEE:

SEVENTH STREET PROPERTIES II                XOMA CORPORATION
1120 Nye Street, Suite 400                  2910 7th Street
San Rafael, CA 94915                        Berkeley, CA  94518

By /s/ Richard K. Robbins                   By  /s/ C.L. Dellio
- ----------------------------                -----------------------------
(Signature)                                          (Signature)

Richard K. Robbins                          C.L. Dellio - V.P Operations
- ----------------------------                -----------------------------
(Print Name & Title)                        (Print name and title)

It is agreed that shell has been completed sufficient for build out to begin as
of May 1, 1988.

By /s/ Richard K. Robbins                   By /s/ C.L. Dellio
- ----------------------------                -----------------------------
(Signature)                                 (Signature)


<PAGE>
                                                                         NOTED
                                                                     AUG 3, 1987
                                                                          H.R.H.

                                  June 26, 1987

Mr. Ho Humphrey
Xoma Corporation
2910 Seventh Street
Berkeley, CA 94710

                     RE: BUILDING E OF AQUATIC PARK CENTER.

Dear Mr. Humphrey:

     On or about the date of this letter, Xoma Corporation ("Xoma") and Seventh
Street Properties II ("Lessor") entered into a lease of Building E at Aquatic
Park Center (the "Lease").

     With respect to Building E, the parties hereby agree as follows:

     1. Right Of First Refusal. Xoma shall have the right of first refusal to
purchase Building E from Lessor if and when Lessor elects to sell its entire
interest in Building E. If Lessor proposes to sell the Building, it shall first
serve written notice on Xoma setting forth the terms on which Building E shall
be sold (the "Initial Notice"). Xoma shall have 15 calendar days after receipt
of the Initial Notice in which to inform Lessor in writing that it wishes to
purchase the Building on the terms set forth in the Initial Notice. Notices
shall be delivered in accordance with the terms of the Lease. Failure of Xoma to
serve such written notice within the 15 day period or to close the sale within
45 days after serving notice on Lessor of its intent to purchase (other than as
a result of Lessor's default) shall be deemed to be a waiver of its right of
first refusal, and Lessor shall be free thereafter to sell Building E to third
parties. Notwithstanding the above, if Lessor proposes to offer more favorable
terms to third parties than set forth in the Initial Notice, then Lessor shall
serve another written notice on Xoma and again go through the procedure set
forth above, provided that Lessor shall not need to serve another written notice
or go through the procedure if Xoma had previously elected to purchase Building
E but failed to close the transaction within the time stated above.


<PAGE>


Mr. Ho Humphrey
June 26, 1987
Page 2

     2. Laboratory Animal Ordinance. If at any time during the term of the
Lease, the City of Berkeley passes an ordinance which prohibits the use of all
laboratory animals, then Xoma may elect to have the rent abated for up to 5,000
square feet of animal laboratory space in Building E and to receive a $15 per
square foot tenant improvement allowance (the "Allowance") for the purpose of
converting such laboratory space to other uses. Xoma may exercise such right
only by serving written notice on Lessor within 30 calendar days after the
ordinance goes into effect. The rent abatement shall commence at the date
specified in Xoma's notice to Lessor, which in no event shall be later than 90
days after the ordinance goes into effect. Notwithstanding anything to the
contrary above, rent shall in no case be abated for more than 180 days. Xoma
shall be responsible for building out all tenant improvements. The Allowance
shall be paid to Xoma upon substantial completion of the improvements and their
approval by Lessor. Nothing herein shall release Xoma from the terms of the
Lease in connection with such tenant improvements including, but not limited to,
the responsibility of having Lessor approve any such tenant improvements in
advance, which approval shall not be unreasonably withheld.

     3. Forgiveness Of Rent. It is agreed that the monthly rent owing pursuant
to Paragraph 4.1 of the Lease shall be forgiven and shall not be payable by Xoma
through the six month anniversary of the Commencement Date. Accordingly, the
first month's rent to be deposited at the execution of the Lease shall be
applied against the rent owing for the first month following the six month
anniversary of the Commencement Date.

     Please confirm by signing below your agreement with this amendment to the
Lease and your acknowledgment that except for this specific amendment, all terms
and conditions of the Lease shall remain unmodified and in full force and
effect.

                                   Sincerely,

                                   SEVENTH STREET PROPERTIES II

                                   By  /s/ Richard K. Robbins
                                   -----------------------------
                                            (Signature)

                                   Richard K. Robbins
                                   -----------------------------
                                   (Print Name And Title)


<PAGE>


Mr. Ho Humphrey
June 26, 1987
Page 3

The terms set forth above are hereby agreed to on 22 July, 1987.

XOMA CORPORATION

By /s/ Steven C. Mendell
- ----------------------------
(Signature)

Steven C. Mendell/ CEO
- ----------------------------
(Print Name & Title)


<PAGE>


                                XOMA CORPORATION

                                   BUILDING E

                                TRIPLE NET LEASE

                                Table Of Contents


Paragraph   Title                                                          Page

1.0         BASIC LEASE TERMS ..............................................1

            1.1        Commencement Of Lease ...............................1
            1.2        Lease Term ..........................................1
            1.3        Monthly Rent ........................................1
            1.4        Lessee's Pro Rata Share .............................1
            1.5        Security Deposit ....................................1
            1.6        Use .................................................1

2.0         PREMISES .......................................................2

            2.1        Description .........................................2
            2.2        Work Of Improvement .................................2
            2.3        Possession ..........................................2

3.0         TERM ...........................................................2

            3.1        Commencement ........................................2
            3.2        Delay In Commencement ...............................2
            3.3        Option To Terminate .................................2
            3.4        Option To Extend Term ...............................2
            3.5        Term ................................................3
            3.6        Fair Market Lease Rate ..............................3

4.0         RENT ...........................................................4

            4.1        Monthly Rent ........................................4
            4.2        Rent Adjustment .....................................4
            4.3        Mode Of Payment .....................................5
            4.4        Triple Net Lease ....................................5
            4.5        Estimated Payments ..................................5
            4.6        Security Deposit ....................................6
            4.7        Late Charges ........................................6

5.0         TAXES ..........................................................7

            5.1        Real Property Taxes .................................7
            5.2        Personal Property Taxes .............................7

6.0         INSURANCE ......................................................8

            6.1        Property/Rental Insurance -
                        Premises ...........................................8
            6.2        Property Insurance - Fixtures And
                        Inventory ..........................................8
            6.3        Lessor's Liability Insurance ........................8
            6.4        Lessee's Liability Insurance ........................8
            6.5        Waiver Of Subrogation ...............................9

                                       -i-


<PAGE>


            6.6        Indemnification .....................................9
            6.7        Plate Glass Replacement .............................9
            6.8        Workers' Compensation Insurance .....................10

7.0         MAINTENANCE ....................................................10

            7.1        Premises ............................................10
            7.2        Building ............................................10
            7.3        Common Areas ........................................10
            7.4        Alterations, Changes And Additions
                        By Lessee ..........................................11
            7.5        Plumbing ............................................11
            7.6        Liens ...............................................11

8.0         MANAGEMENT .....................................................12

9.0         UTILITIES AND SERVICES .........................................12

            9.1        Premises ............................................12
            9.2        Common Areas ........................................12

10.0        USE OF PREMISES ................................................13

            10.1       Use .................................................13
            10.2       Suitability .........................................13
            10.3       Uses Prohibited .....................................13
            10.4       Lessee's Warranty ...................................14

11.0        DEFAULT PROVISIONS .............................................14

            11.1       Insolvency ..........................................14
            11.2       Non-Payment, Breach Or Vacating .....................14
            11.3       Default Under Other Leases ..........................15
            11.4       Lessor's Right To Relet .............................15
            11.5       Right To Terminate ..................................15
            11.6       Default By Lessor ...................................15

12.0        EXPIRATION OR TERMINATION ......................................16

            12.1       Surrender Of Possession .............................16
            12.2       Holding Over ........................................16
            12.3       Voluntary Surrender .................................16

13.0        CONDEMNATION OF PREMISES .......................................16

            13.1       Total Condemnation ..................................16
            13.2       Partial Condemnation ................................17
            13.3       Award To Lessee .....................................17

14.0        ENTRY BY LESSOR ................................................17

15.0        INDEMNIFICATION ................................................18

16.0        ASSIGNMENT AND SUBLETTING ......................................18

17.0        DAMAGE OR DESTRUCTION ..........................................19

            17.1       Right To Termination On Destruction
                        Of Premises ........................................19
            17.2       Repairs By Lessor ...................................19


                                      -ii-

<PAGE>


            17.3       Reduction of Rent During Repairs ....................19
            17.4       Arbitration .........................................19
            17.5       Lessor's Overriding Right To
                        Terminate ..........................................19

18.0        MISCELLANEOUS PROVISIONS .......................................20

            18.1       Waiver ..............................................20
            18.2       Successors And Assigns ..............................20
            18.3       Notices .............................................20
            18.4       Partial Invalidity ..................................20
            18.5       Number And Gender ...................................20
            18.6       Descriptive Headings ................................20
            18.7       Time Is Of The Essence ..............................20
            18.8       Entire Agreement ....................................20
            18.9       Memorandum Of Lease .................................21
            18.10      Applicable Law ......................................21
            18.11      Corporate Authority .................................21
            18.12      Litigation Expense ..................................21
            18.13      Subordination Of Leasehold ..........................21
            18.14      Lessee's Certificate ................................21
            18.15      Attornment ..........................................22
            18.16      Day .................................................22
            18.17      Brokers .............................................22

EXHIBIT A - DESCRIPTION OF THE PREMISES AND PROPERTY
EXHIBIT B - WORK TO BE PERFORMED BEFORE OCCUPANCY OF PREMISES

                                      -iii-


<PAGE>


                                XOMA CORPORATION

                                   BUILDING E

                                TRIPLE NET LEASE

     LEASE made and entered into this 22 day of July 1987, between SEVENTH
STREET PROPERTIES II ("Lessor") and XOMA CORPORATION ("Lessee").

                                R E C I T A L S:

     A. Concurrently with the execution of this Lease, Lessee is entering into
three other leases, specifically one with Lessor for approximately 6,720 square
feet in Building C at Aquatic Park Center (the "Building C Lease") another with
Lessor for approximately 20,000 square feet in Building F at Aquatic Park Center
(the "Building F Lease"), and another with Seventh Street Properties, an
affiliate of Lessor, for approximately 24,275 square feet at 890 Heinz Street,
Berkeley, California (the "Heinz Street Lease").

     B. The Building C Lease, the Heinz Street Lease and this Lease are intended
to be read together so that a breach of one is deemed a breach of the other.

                               A G R E E M E N T:

     NOW, THEREFORE, the parties hereby agree as follows:

     1.0 BASIC LEASE TERMS.

     1.1 Commencement Of Lease: The term of this Lease shall commence on the
earlier of:

     a. The date Lessor notifies Lessee in writing that the construction to be
performed by Lessor pursuant to Paragraph 2.2 hereof has been substantially
completed. Substantial completion shall occur when the Premises are in such
condition as to permit Lessor to file a Notice of Completion with respect to its
work; or

     b. The date Lessee actually commences to do business at the Premises.

     1.2 Lease Term: Through April 30, 2003.

     1.3 Monthly Rent: $38,500.

     1.4 Lessee's Pro Rata Share: 29.17%.

     1.5 Security Deposit: $38,500.

     1.6 Use: Pharmaceutical manufacturing, offices, laboratories, shipping and
receiving relating to pharmaceutical products.

                                      -1-


<PAGE>


     2.0 PREMISES.

     2.1 Description. Lessor hereby leases to Lessee all of Building E (the
"Premises") constituting approximately 35,000 square feet, which constitute a
portion of a larger piece of real property owned by Lessor and known as the
Aquatic Park Center (the "Property"). Exhibit A attached hereto further
describes the Premises and the Property.

     2.2 Work Of Improvement. The respective obligations of Lessor and Lessee to
perform the work and supply material and labor to prepare the Premises for
occupancy are set forth in Exhibit B attached hereto and incorporated herein.
Lessor and Lessee shall expend all funds and do all acts required of them
respectively in Exhibit B and shall have the work performed promptly and
diligently in a first-class, workmanlike manner. Lessee shall not commence
construction of the improvements to be undertaken by Lessee until Lessor has
approved in writing the final drawings for said improvements, which approval
shall neither be unreasonably withheld nor delayed.

     2.3 Possession. Lessor shall deliver occupancy of the Premises to Lessee on
the Commencement Date as hereinafter defined.

     3.0 TERM.

     3.1 Commencement. The Lease shall commence on the date specified in
Paragraph 1.1 above (the "Commencement Date") and shall continue thereafter for
the term specified in Paragraph 1.2 above (the "Initial Term"), unless sooner
terminated pursuant to this Lease.

     3.2 Delay In Commencement. If for any reason Lessor cannot deliver
possession of the Premises to Lessee on the Commencement Date, such failure
shall not affect the validity of this Lease nor shall it extend the Term or
render Lessor liable to Lessee for any loss or damage resulting therefrom;
except that if possession is not delivered to Lessee on the Commencement Date,
Tenant shall not be obligated to pay rent until possession of the Premises is
tendered to Lessee. Notwithstanding the above, if Lessor does not deliver
possession of the Premises to Lessee by June 30, 1988, then Lessee shall have
the option of terminating this Lease by serving written notice on Lessor on or
before July 15, 1988.

     3.3 Option To Terminate. Lessee is hereby granted an option to terminate
the Lease effective April 30, 1998 by giving written notice to Lessor of
Lessee's intent to terminate (the "Termination Notice") on or before July 31,
1997.

     3.4 Option To Extend Term. Lessee is hereby granted an option to extend the
term for a five year period following the expiration of the Initial Term (the
"Option Term") by giving written notice to the Lessor of Lessee's intent to
exercise such option (the "Option Notice") at least 270 days before the
expiration of the Initial Term. The Option Term shall be on the same terms and
conditions in effect immediately before the end of the Initial Term, except that
the rent shall

                                       -2-


<PAGE>


be set at 95% of the fair market lease rate for comparable space in the Berkeley
area, provided that in no event shall the rental rate for the Option Term be
less than the rental rate as of the last day of the Initial Term.
Notwithstanding anything to the contrary above, if Lessee is in default in the
payment of rent, in the making of other payments required to be made by Lessee
under this lease or otherwise under this Lease on the date the Option Notice is
delivered to Lessor or on the date the Option Term is to commence, the Option
Term shall not commence and this Lease shall expire at the end of the Initial
Term.

     3.5 Term. All references to the "Term" in this Lease shall include the
Initial Term set forth in Paragraph 3.1 plus any extensions pursuant to
Paragraph 3.4.

     3.6 Fair Market Lease Rate. Lessor shall give Lessee notice ("Lessor's
Notice") of the fair market lease rate after receiving Lessee's written notice
of intent to exercise the Option, provided that Lessor's Notice shall not be
delivered later than 120 days prior to the commencement of the Option Term. If
Lessee believes that the fair market lease rate as established by Lessor is
incorrect, Lessee shall notify Lessor in writing within 20 days of Lessee's
receipt of the notice from Lessor that Lessee desires to submit the matter to
appraisal with a designation of an MAI qualified appraiser. If Lessor agrees
with the identity of such appraiser, it shall within 10 days notify the
appraiser and Lessee that such appraiser shall determine the fair market lease
rate (including fair market increases during the Option Term). If not, Lessor
shall submit the name of its appraiser to Lessee within said 10 days. The two
appraisers so selected shall choose a third appraiser and the three together
shall determine the fair market lease rate (including fair market increases
during the Option Term). If the two appraisers cannot select a third appraiser
within 20 days after Lessor submits the name of its appraiser, either party may
at any time apply to the presiding judge of any court of competent jurisdiction
for the appointment of the third appraiser. If the three appraisers are unable
to agree on the fair market lease rate they shall each determine the fair market
lease rate assuming annual CPI increases during the Option Term and then average
their determinations by tossing out the high and low appraisal and accepting the
middle appraisal as the fair market lease rate. The costs of the appraisal
process shall be borne by Lessee unless the fair market lease rate as determined
by the appraisal is more than 10% below the lease rate set forth in Lessor's
Notice in which case Lessor and Lessee shall share the costs of the appraisal
process equally. The appraisal process shall be completed as quickly as
reasonably possible. If for any reason the Option Term commences prior to the
conclusion of the appraisal process, Lessee shall continue to pay the monthly
base rent then in effect to Lessor plus 10% of such amount, which 10% only shall
be held by Lessor in escrow pending completion of the appraisal process, at
which time all funds held in escrow shall be distributed to Lessee and/or Lessor
in accordance with the outcome of the appraisal process, and Lessee shall
subsequently be bound by the lease rate as determined by the appraisal process.
The rent during the Option Term shall continue to be adjusted as agreed upon

                                       -3-


<PAGE>


between Lessor and Lessee or as determined by the appraisal process.

     4.0 RENT

     4.1 Monthly Rent. Lessee shall pay to Lessor as rent for the Premises in
advance on the first day of each calendar month of the Term without deduction,
offset, prior notice or demand, in lawful money of the United States, the sum
specified in Paragraph 1.3 above which is based on $1.10 per square foot and the
square footage set forth in Paragraph 2.1. The rent owing shall be adjusted as
necessary if the actual square footage is shown to be other than as set forth in
Paragraph 2.1. Notwithstanding the above, Lessee shall not be required to pay
rent until the Commencement Date under the Building C Lease. If the Commencement
Date is not the first day of a calendar month, the first monthly installment of
such rent shall be applied on a per diem basis against payment of the rent from
the Commencement Date until the first day of the first succeeding calendar
month. Any unused portion of said amount shall be applied against payment of the
rent for such first succeeding calendar month, and the balance of the rent for
that month shall be due on the first day thereof. Concurrent with Lessee's
execution of this Lease, Lessee shall pay to Lessor the first monthly
installment of rent.

     4.2 Rent Adjustment. For the period through April 30, 1998 the base rent
set forth in Paragraph 4.1 above shall be adjusted as follows. On October 1,
1990 and every three years thereafter (the "Adjustment Dates"), the base rent
shall be adjusted by the percentage increase in the Consumer Price Index (all
items) for all urban consumers in the San Francisco-Oakland metropolitan area,
published by the United States Department of Labor, Bureau of Labor Statistics.
The monthly rent until the next Adjustment Date shall be the greater of (a) the
rent in effect immediately before the Adjustment Date or (b) the initial rent
set forth in Paragraph 4.1 above multiplied by a fraction, the numerator of
which shall be said Index number for the calendar month three months prior to
the Adjustment Date and the denominator of which shall be said Index number for
the calendar month three months prior to the first full calendar month following
the Commencement Date. Notwithstanding the above, in no case shall the increase
as of any Adjustment Date exceed 21% plus the Carry Forward. As used above, the
"Carry Forward" shall mean the percentage increases in CPI which are not used at
earlier Adjustment Dates to adjust the rent because of this limitation. For
example, if the CPI increase is 15% on October 1, 1990, then the Carry Forward
is six percent and the CPI increase on October 1, 1993 shall be the actual CPI
increase, not to exceed 27%. If the actual CPI increase on October 1, 1993 were
23%, then the Carry Forward to October 1, 1996 would be four percent. Should the
Bureau discontinue the publication of said Index numbers, or publish the same
less frequently, or alter the same in some other manner, then Lessor shall adopt
a substitute index or procedure which reasonably reflects consumer prices.
Commencing May 1, 1998, the adjustment mechanism set forth above shall be
discarded and rent shall be adjusted to 95% of

                                       -4-


<PAGE>


the fair market lease rate as of May 1, 1998 for comparable space in the
Berkeley area, provided that in no event shall the new rental rate be less than
the rental rate in effect immediately before such adjustment. (Adjustments
subsequent to May 1, 1998 shall be determined in the course of establishing the
fair market lease rate.) On or before January 1, 1998, Lessor shall provide
Lessee with notice of the May 1, 1998 fair market lease rate. The fair market
lease rate shall then be determined in accordance with Paragraph 3.6, and the
notice referenced above shall be deemed "Lessor's Notice."

     4.3 Mode Of Payment. Lessee shall pay all rent due Lessor at Lessor's
address set forth on the signature page hereof, or any such other place as
Lessor may designate from time to time in writing.

     4.4 Triple Net Lease. This Lease is what is commonly called a "Net, Net,
Net Lease," it being understood that Lessor shall receive the rent set forth
herein free and clear of any and all other impositions, taxes, liens, charges or
expenses of any nature whatsoever in connection with the ownership and operation
of the Premises. All references herein to Lessee's pro rata share of any expense
shall mean the total expense of any such item multiplied by a fraction, the
numerator of which shall be the total floor area of the Premises and the
denominator of which shall be the total floor area available for lease by Lessor
of Buildings C, E and F on the Property. "Floor area" shall be measured from the
exterior surface of all exterior walls and from the center of all walls
separating the Premises from adjacent premises. Based upon the square footage
numbers set forth in Paragraph 2.1, Lessee's pro rata share has been calculated
and is set forth in Paragraph 1.4. Lessee's pro rata share shall be adjusted as
necessary if the actual square footage is shown to be other than as set forth in
Paragraph 2.1 or upon any subdivision of the Property. In the event of
non-payment of all or any portion of such charges, costs and expenses, Lessor
shall have the same rights and remedies as provided in this Lease for failure of
Lessee to pay rent. Lessee shall in no event be entitled to any abatement or
reduction of rent or other monetary sums payable hereunder, except as expressly
provided herein, notwithstanding any present or future law to the contrary.

     4.5 Estimated Payments. Lessee shall be notified by Lessor of Estimated
Payments for taxes, insurance, maintenance of common areas and common area
utilities and services from time to time. The Estimated Payments shall be paid
by Lessee together with rent, on the first day of each month throughout the
Term. The Estimated Payments may be increased or decreased by Lessor upon 30
days' written notice to Lessee based upon statements received or charges
incurred by Lessor, information available to Lessor as to the probable cost of
expected charges and expenses, or the reasonable estimate of Lessor as to the
probable amount of expected charges or expenses. Lessor shall be entitled to
retain the monies received from such payments in its general fund pending
payment of all such costs and charges. No more frequently than once each
calendar quarter, the actual costs shall be determined by Lessor, and Lessee
shall remit to Lessor on demand its unpaid pro rata share of the actual expense.
In the event Lessee paid more than its pro

                                       -5-


<PAGE>


rata share of the actual expenses for such period of time, Lessor shall apply
such overpayment towards the next Estimated Payments owing by Lessee. At the
termination of this Lease, an accounting for such charges and expenses shall be
made to the nearest practical accounting period, and Lessee shall pay to Lessor
any balance due, or the Lessor shall refund to Lessee any excess amount paid.

     4.6 Security Deposit. Concurrent with Lessee's execution of this Lease,
Lessee shall deposit with Lessor as a security deposit the sum specified in
Paragraph 1.5 above (the "Deposit"). On May 1, 1998 and May 1, 2003 (unless the
Lease is terminated or the Option is not exercised, as the case may be) Lessee
shall increase the Deposit to that amount which is equal to the newly
established monthly rental. The Deposit shall be held by Lessor as a security
deposit for the faithful performance by Lessee of all terms, covenants, and
conditions of this Lease to be kept and performed by Lessee during the Term. If
Lessee defaults with respect to any provisions of this Lease, including but not
limited to the provisions relating to the payment of rent and any of the
monetary sums due hereunder, Lessor may (but shall not be required to) use,
apply or retain any part or all of the Deposit for the payment of any amount
which Lessor may spend or become obligated to spend by reason of Lessee's
default or to compensate Lessor for any loss or damage which Lessor may suffer
by reason of Lessee's default. If any portion of the Deposit is so used or
applied, Lessee shall, within 10 days after written demand therefor, deposit
cash with Lessor in an amount sufficient to restore the Deposit to its original
amount; Lessee's failure to do so shall be a material breach of this Lease.
Lessor shall not be required to keep the Deposit separate from its general
funds, and Lessee shall not be entitled to interest on the Deposit. If Lessee
shall fully and faithfully perform every provision of this Lease to be performed
by it, the Deposit or any balance thereof shall be returned to Lessee (or, at
Lessor's option, to the last assignee of Lessee's interests hereunder) at the
expiration of the Term and after Lessee has vacated the Premises. In the event
of termination of Lessor's interest in this Lease, Lessor shall transfer the
Deposit to Lessor's successor in interest, whereupon Lessee agrees to release
Lessor from all liability for the return of the Deposit or the accounting
therefor.

     4.7 Late Charges. Lessee hereby acknowledges that late payment by Lessee to
Lessor of rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this Lease, the exact amount of which will be extremely
difficult to ascertain. Such costs include, but are not limited to, processing
and accounting charges, and late charges which may be imposed on the Lessor by
the terms of any mortgage or trust deed covering the Premises. Accordingly, if
any installment of rent or any other sum due from Lessee shall not be received
by Lessor or Lessor's designee within 10 days after such amount shall be due,
Lessee shall pay to Lessor a late charge equal to five percent of such overdue
amount. The parties hereby agree that such late charge represents a fair and
reasonable estimate of the costs Lessor will incur by reason of late payment by
Lessee. Acceptance of such late charge by Lessor shall in no event constitute a
waiver of

                                      -6-


<PAGE>


Lessee's default with respect to such overdue amount, nor prevent a Lessor from
exercising any of the other rights and remedies granted hereunder.

     5.0 TAXES.

     5.1 Real Property Taxes. Lessee agrees to pay to Lessor in addition to the
rent and other charges herein its pro rata share of all Designated Real Property
Taxes in accordance with Paragraph 4.5. As used herein, "Real Property Taxes"
shall include any form of assessment, license, fee, rent, tax, levy, penalty or
tax imposed by any authority having the direct or indirect power to tax,
including any improvement district, as against any legal or equitable interest
of Lessor in the Property or as against Lessor's business of renting the
Property. As used herein, "Designated Real Property Taxes" shall mean all Real
Property Taxes except those Real Property Taxes which are shown on the tax bill
for the Property as applying to the improvements constituting Buildings A and B,
as shown on Exhibit B, and 86.82% of (a) the Real Property Taxes applying to the
land and (b) special assessments against the Property. Such percentage was
determined by comparing the square footage of all of the land within the
Property to the square footage of all such land not occupied by Buildings A and
B, plus 14,000 square feet of the Property attributed to Buildings A and B.
Lessee's share of Designated Real Property Taxes shall be equitably prorated to
cover only the period of time within the fiscal tax year during which this Lease
is in effect. With respect to any assessments which may be levied against or
upon the Premises, and which may be paid in annual installments, only the amount
of such annual installments (with appropriate proration for any partial year)
and interest due thereon shall be included within the computation of the annual
Designated Real Property Taxes. Lessor represents that, to the best of its
knowledge, there are no assessment or improvement districts being planned which
would affect the Property other than as in effect as of the date of this Lease.
If the Property becomes subdivided, the formulas above shall continue to apply
(unless Building E is split off into a separate parcel without any other
buildings) but Lessee's pro rata share and the percentage shown above shall be
adjusted to reflect the new square footage of the resulting parcels. If Building
E is split off from the Property into a separate parcel without any other
buildings, it shall be assessed by itself and Lessee shall be responsible for
all of the Real Property Taxes relating thereto.

     5.2 Personal Property Taxes. Lessee shall pay before delinquency all taxes
levied or assessed on Lessee's fixtures, improvements, furnishings, merchandise,
equipment and personal property in and on the Premises, whether or not affixed
to the real property. If Lessee in good faith contests the validity of any such
personal property taxes, then Lessee shall at its sole expense defend itself and
Lessor against the same and shall pay and satisfy any adverse determination or
judgment that may be rendered thereon and shall furnish Lessor with a surety
bond satisfactory to Lessor in an amount equal to 150% of such contested taxes.
Lessee shall indemnify Lessor against liability for any such taxes and/or any
liens placed on the Premises or the Property in connection with such taxes.

                                      -7-


<PAGE>


[If at any time after any tax or assessment has become due or payable Lessee or
its legal representative neglects to pay such tax or assessment, Lessor shall be
entitled, but not obligated, to pay the same at any time thereafter and such
amount so paid by Lessor shall be repaid by Lessee to Lessor with Lessee's next
rent installment together with interest at the highest rate allowable by law.

     6.0 INSURANCE.

     6.1 Property/Rental Insurance - Premises. During the Term, Lessor shall
keep the Property insured against loss or damage by fire and those risks
normally included in the term "all risk" including (a) flood coverage at the
election of Lessor, (b) earthquake coverage at the reasonable election of
Lessor, (c) coverage for loss of rents and (d) boiler and machinery coverage if
the Lessor deems necessary. Any deductibles shall be paid by Lessee if the
deductible arises from damage solely to the Premises. If the damage covers a
greater portion of the Property than the Premises, then Lessee shall pay that
portion of the deductible which the total floor area of the Premises bears to
the total floor area of the Property which is available for lease by Lessor and
which suffered damage. The amount of such insurance shall be not less than 100%
of the replacement value of the Premises. Any recovery received from said
insurance policy shall be paid to Lessor. Lessee, in addition to the rent and
other charges provided herein, agrees to pay to Lessor its pro rata share of the
premiums for all insurance for the Property, excluding that insurance applicable
to Buildings A and B as shown by the insurance company (or its broker) issuing
such insurance. The insurance premiums shall be paid in accordance with
Paragraph 4.5. Lessee shall pay to Lessor any deductibles owing within 15 days
after receipt of notice from Lessor of the amount owing.

     6.2 Property Insurance - Fixtures And Inventory. During the Term, Lessee
shall, at its sole expense, maintain insurance with "all risk" coverage on any
fixtures, leasehold improvements, furnishings, merchandise, equipment or
personal property in or on the Premises, whether in place as of the date hereof
or installed hereafter, for the full replacement value thereof, and Lessee shall
also have sole responsibility and cost for maintaining any other types of
insurance relating to Lessee's use of the Premises. Any deductibles shall be
paid by Lessee.

     6.3 Lessor's Liability Insurance. During the Term, Lessor shall maintain a
policy or policies of comprehensive general liability insurance insuring Lessor
(and such others as designated by Lessor) against liability for bodily injury,
death and property damage on or about the Property, with combined single limit
coverage of not less than $2,000,000.

     6.4 Lessee's Liability Insurance. During the Term, Lessee shall, at its
sole expense, maintain for the mutual benefit of Lessor and Lessee,
comprehensive general liability and property damage insurance against claims for
bodily injury, death or property damage occurring in or about the Premises or
arising out of the use or occupancy of the Premises, with combined single limit
coverage of not less than $2,000,000.

                                       -8-


<PAGE>


The limits of such insurance shall not limit the liability of Lessee. Lessee
shall furnish to Lessor prior to the Commencement Date, and at least 30 days
prior to the expiration date of any policy, certificates indicating that the
liability insurance required by Lessee above is in full force and effect, that
Lessor has been named as an additional insured; and that all such policies will
not be cancelled unless 30 days' prior written notice of the proposed
cancellation has been given to Lessor. The insurance shall be with insurers
reasonably approved by Lessor and with policies in form reasonably satisfactory
to Lessor. Said policies shall provide that Lessor, although an additional
insured, may recover for any loss suffered by Lessor by reason of Lessee's
negligence, and shall include a broadform liability endorsement.

     6.5 Waiver Of Subrogation. Lessor hereby releases Lessee, and Lessee hereby
releases Lessor, and their respective officers, agents, employees and servants,
from any and all claims or demands of damages, loss, expense or injury to the
Premises, or to the furnishings and fixtures and equipment, or inventory or
other property of either Lessor or Lessee in, about or upon the Premises, which
is caused by or results from perils, events or happenings which are the subject
of insurance carried by the respective parties and in force at the time of any
such loss; provided, however, that such waiver shall be effective only to the
extent permitted by the insurance covering such loss and to the extent such
insurance is not prejudiced thereby. Each party shall cause each insurance
policy obtained by it to provide that the insurance company waives all right of
recovery by way of subrogation against either party in connection with any
damage covered by any policy.

     6.6 Indemnification. Except to the extent of intentional misconduct by
Lessor or Lessor's negligence, Lessee will indemnify Lessor and save it harmless
from and against any and all claims, actions, damages, liability and expense in
connection with loss of life, personal injury and/or damage to property arising
from or out of any occurrence in, upon or at the Premises, or the occupancy or
use by Lessee of the Premises or any part thereof, or occasioned wholly or in
part by any acts or omissions of Lessee, its agents, contractors, employees,
servants, licensees or concessionaires or by anyone permitted to be on the
Premises by Lessee. In case Lessor shall be made a party to any such litigation
commenced by or against Lessee, then Lessee shall protect and hold Lessor
harmless from all claims, liabilities, costs and expenses, and shall pay all
costs, expenses and reasonable legal fees incurred by Lessor in connection with
such litigation.

     6.7 Plate Glass Replacement. Lessee shall replace at its sole expense, any
and all plate glass and other glass in and about the Premises which is damaged
or broken by vandalism. If any plate glass or other glass in and about the
Premises is damaged or broken by causes other than vandalism, then Lessee shall
pay Lessor an amount equal to Lessor's cost of replacement, provided that such
amount shall not exceed the deductible then in effect on Lessor's insurance
policy, if any, covering the damaged glass. Nothing herein shall be construed to
require Lessor to carry plate glass insurance.

                                       -9-


<PAGE>


     6.8 Workers' Compensation Insurance. Lessee shall, at its sole expense,
maintain and keep in force during the Term a policy or policies of Workers'
Compensation Insurance and any other employee benefit insurance sufficient to
comply with all applicable laws, statutes, ordinances and governmental rules,
regulations or requirements.

     7.0 MAINTENANCE.

     7.1 Premises. Throughout the Term, Lessee agrees to keep and maintain all
improvements and appurtenances upon the Premises, including all sewer
connections, plumbing, heating and cooling appliances, wiring and glass, in good
order and repair including the replacement of such improvements and
appurtenances when necessary. Lessee hereby expressly waives the provisions of
any law permitting repairs by a tenant at the expense of a landlord, including,
without limitation, all rights of Lessee under Sections 1941 and 1942 of the
California Civil Code. Lessee agrees to keep the Premises clean and in sanitary
condition as required by the health, sanitary and police ordinances and
regulations of any political subdivision having jurisdiction. Lessee further
agrees to keep the interior of the Premises, such as the windows, floors, walls,
doors, showcases and fixtures clean and neat in appearance and to remove all
trash and debris which may be found in or around the Premises. If Lessor deems
any repairs and/or maintenance to be made by Lessee necessary and Lessee refuses
or neglects to commence such repairs and/or maintenance and complete the same
with reasonable dispatch upon demand, Lessor may enter the Premises and cause
such repairs and/or maintenance to be made and shall not be responsible to
Lessee for any loss or damage occasioned thereby except to the extent that
Lessee's personal property is damaged by the intentional misconduct or
negligence of Lessor or its contractors. Lessee agrees that upon demand, it
shall pay to Lessor the cost of any such repairs, together with accrued interest
from the date of payment at the highest rate allowable by law.

     7.2 Building. Lessor shall maintain the foundation, roof and exterior walls
(the "Structural Components") of the Premises in reasonably good order and
repair, except that damage occasioned by the act of Lessee shall be repaired by
Lessor at Lessee's expense. Lessee shall have the obligation to notify Lessor,
in writing, of any repairs or maintenance to the Structural Components which may
be required, and Lessor shall have a reasonable time to make such repairs. The
manner and method of maintenance and repair of the Structural Components shall
be at the reasonable discretion of Lessor. Lessee, in addition to the rent and
other charges provided herein, agrees to pay to Lessor all of the costs of
maintaining the Structural Components as billed to Lessee by Lessor.

     7.3 Common Areas. Lessor shall maintain the common areas of the Property
which shall include without limitation the landscaping, plazas and parking lots
in reasonably good order and condition, except that damage occasioned by the act
of Lessee shall be repaired by Lessor at Lessee's expense. Lessee shall have the
obligation to notify Lessor, in writing, of any repairs or maintenance to the
common areas which may be

                                      -10-


<PAGE>


required, and Lessor shall have a reasonable time to make such repairs. The
manner and method of maintenance and repair of the common areas shall be at the
reasonable discretion of Lessor. Lessee, in addition to the rent and other
charges provided herein, agrees to pay to Lessor its pro rata share of the costs
of maintaining the common areas in accordance with Paragraph 4.5.

     7.4 Alterations, Changes And Additions By Lessee. No changes, alterations,
or additions shall be made by Lessee to the Premises without the prior written
consent of Lessor which Lessor will not unreasonably withhold. Notwithstanding
the above, non-structural changes aggregating no more than $10,000 in any 12
month period may be made by Lessee without Lessor's consent. As used herein,
alterations include utility installations such as ducting, power panels,
fluorescent fixtures, base heaters, conduit and wiring. As a condition to giving
such consent, Lessor may require that Lessee agree to remove any such
alterations, additions or improvements at the expiration of the Term and to
restore the Premises to their prior condition. As a further condition to giving
such consent, Lessor may require Lessee to provide Lessor, at Lessee's sole cost
and expense, with a lien and completion bond in an amount equal to one and
one-half times the estimated cost of such improvements, to insure Lessor against
any liability for mechanics' and materialmen's liens and to insure completion of
the work. All changes, alterations or additions to be made to the Premises shall
be under the supervision of a competent architect or competent licensed
structural engineer and made in accordance with plans and specifications which
have been furnished to and approved by Lessor prior to commencement of work.
Lessor shall not unreasonably withhold its approval of such proposed
alterations. If the written consent of Lessor to any proposed alterations by
Lessee shall have been obtained, Lessee agrees to advise Lessor in writing of
the date upon which such alterations will commence in order to permit Lessor to
post a notice of nonresponsibility. All such alterations, changes and additions
shall be constructed in a good and workmanlike manner in accordance with all
ordinances and laws relating thereto. Any such changes, alterations or additions
to or on the Premises shall remain for the benefit of and become the property of
Lessor, unless Lessor requires the removal by giving Lessee written notice
within 30 days before the date Lessee is to vacate the Premises, in which case
Lessee shall remove such changes, alterations and additions and restore the
Premises to the condition they were in prior to such changes, alterations or
additions.

     7.5 Plumbing. Lessee shall not use the plumbing facilities for any purpose
other than that for which they were constructed. The expense of any breakage,
stoppage or other damage relating to the plumbing and resulting from the
introduction by Lessee, its agents, employees or invitees of foreign substances
into the plumbing facilities shall be borne by Lessee.

     7.6 Liens. Lessee shall keep the Premises free from any liens arising out
of work performed, materials furnished or obligations incurred by Lessee and
shall indemnify, hold harmless and defend Lessor from any liens and encumbrances


                                      -11-


<PAGE>


arising out of any work performed or materials furnished by or at the direction
of Lessee. In the event that Lessee shall not, within 20 days following the
imposition of any such lien, cause such lien to be released of record by payment
or posting of a proper bond, Lessor shall have, in addition to all other
remedies provided herein and by law, the right, but not the obligation, to cause
the same to be released by such means as it shall deem proper, including payment
of the claim giving rise to such lien. All such sums paid by Lessor and all
expenses incurred by it in connection therewith including attorneys' fees and
costs shall be payable to Lessor by Lessee on demand with interest at the
highest rate allowable by law. Lessor shall have the right at all times to post
and keep posted on the Premises any notices permitted or required by law, or
which Lessor shall deem proper, for the protection of Lessor and the Premises,
and any other party having an interest therein, from mechanics' and
materialmen's liens, and Lessee shall give to Lessor at least 10 business days'
prior written notice of the expected date of commencement of any work relating
to alterations or additions to the Premises.

     8.0 MANAGEMENT.

     Lessee shall bear its share of the costs to Lessor of managing the
Property. Lessee understands that Wareham Property Group, or another affiliated
or unaffiliated third party will be responsible for the management of the
Property. For the period through April 30, 1998, Lessee shall pay to Lessor a
property management fee equal to five percent of the monthly rent. Thereafter,
the monthly property management fee payable by Lessee shall be equal to the
monthly property management fee owing by Lessee immediately prior to May 1,
1998, subject to adjustment as follows. Commencing May 1, 1998 and each
anniversary thereafter, the monthly property management fee shall be adjusted
upwards by increases in the CPI between the Adjustment Date and the same date
one year earlier. The monthly property management fee shall be payable with
monthly rent.

     9.0 UTILITIES AND SERVICES.

     9.1 Premises. Lessee shall pay prior to delinquency throughout the Term the
cost of water, gas, heating, cooling, sewer, telephone, electricity, garbage,
air conditioning and ventilating, janitorial services and all other materials
and utilities supplied to the Premises, provided that if payment is to be made
to Lessor, it shall be made by Lessee within 30 days of receipt of the statement
for such charges.

     9.2 Common Areas. Lessor shall provide first-class landscaping, utilities,
janitorial and security services for the common areas of the Property. Lessee
shall bear its pro rata share of such common area costs to Lessor in providing
such services in accordance with Paragraph 4.5. Security services shall include
hiring of guards in the discretion of Lessor during hours determined by Lessor.
Notwithstanding the above, any extraordinary landscaping, utilities, janitorial
and/or security services incurred on the Property as a result of special events
held by the tenants of Buildings A and B shall not be included in such common
area costs.

                                      -12-


<PAGE>


     10.0 USE OF PREMISES.

     10.1 Use. The Premises shall be used and occupied by Lessee for only the
purposes specified in Paragraph 1.6 and for no other purposes whatsoever without
obtaining the prior written consent of Lessor which shall not be unreasonably
withheld.

     10.2 Suitability. This Lease shall be subject to all applicable zoning
ordinances and to any municipal, county and state laws and regulations governing
and regulating the use of the Premises. Lessee acknowledges that neither Lessor
nor Lessor's agent has made any representation or warranty as to the suitability
of the Premises for the conduct of Lessee's business.

     10.3 Uses Prohibited.

     a. Rate Of Insurance. Lessee shall not do or permit anything to be done in
or about the Premises which will cause the existing rate of insurance upon the
Premises (unless Lessee shall pay an increased premium as a result of such use
or acts) or cause the cancellation of any insurance policy covering said
Premises, nor shall Lessee sell or permit to be kept, used or sold in or about
such Premises any articles which may be prohibited by a standard form policy of
fire insurance.

     b. Interfere With Other Tenants. Lessee shall not do or permit anything to
be done in or about the Premises which will in any way obstruct or unreasonably
interfere with the rights of other tenants or occupants of the Property or
injure or annoy them or use or allow the Premises to be used for any unlawful or
objectionable purpose, nor shall Lessee cause, maintain or permit any nuisance
in, or about the Premises. Lessee shall not commit or suffer to be committed any
waste in or upon the Premises.

     c. Applicable Laws. Lessee shall not use the Premises or permit anything to
be done in or about the Premises which will in any way conflict with any law,
statute, zoning restriction, ordinance, governmental rule, regulation or
requirements of duly constituted public authorities whether now in force or
which may hereafter be enacted or promulgated. Lessee shall at its sole cost and
expense properly comply with all laws, statutes, ordinances and governmental
rules, regulations or requirements now in force or which may hereafter be in
force and with the requirements of any board of fire underwriters or other
similar body now or hereafter constituted relating to or affecting the
condition, use or occupancy of the Premises. The judgment of any court of
competent jurisdiction or the admission of Lessee in any action against Lessee,
whether Lessor be a party thereto or not, that Lessee has violated any law,
statute, ordinance or government rule, regulation or requirement, shall be
conclusive of that fact as between Lessor and Lessee.

     d. Signs. Lessee shall not place any sign upon the Premises or conduct any
auction thereon without Lessor's prior written consent.

                                      -13-


<PAGE>


     10.4 Lessee's Warranty. Lessee warrants that its use of the Premises
presently complies and shall comply with applicable federal, state and local
laws and regulations pertaining to (i) the use, storage and disposal of
radiological materials and/or toxic chemicals, (ii) the disposal of hazardous
waste and (iii) the safety of persons on the Premises, including but not limited
to, the general industry safety orders as set forth in Title 8 of the California
Administrative Code. Lessee further warrants that it will not interfere with any
actions by Lessor made in furtherance of the above laws and regulations and it
shall comply with any reasonable procedures and/or regulations promulgated by
Lessor from time to time in connection with the matters covered by such laws and
regulations, provided that Lessor shall have no duty to establish any procedures
or regulations or to supervise in any way Lessee's activities on the Premises.
Lessee warrants that all governmental inspections of the Premises as required
under the laws referenced above have been made and will be made, and Lessee
shall deliver within 15 days of the date hereof to Lessor a copy of the reports
of each such inspection most recently conducted. Lessee shall provide a copy of
the reports for each such future inspection within 15 days of Lessee's receipt
of such report. Except in instances when a governmental report of such
inspection has been made within the last 12 month period, Lessee shall obtain at
its sole cost an inspection by a private engineering firm, resulting in a
written report specifying Lessee's compliance, or enumerating the reasons for
Lessee's lack of compliance, with such regulations. Lessee indemnifies and shall
hold Lessor harmless from a breach of the above warranty and from any claim
arising from Lessee's particular use of the Premises, including but not limited
to, (a) the disposal or use of hazardous waste, or (b) the disposal or escape of
odorous, carcinogenic and/or pathogenic exhaust from the Premises. Lessee shall
pay all of Lessor's costs and reasonable attorneys' fees arising from a breach
of Lessee's warranty set forth above, whether or not litigation is commenced,
including but not limited to, the costs of defending any claims made against
Lessor as a result of such breach. Lessor shall have the right to defend such
claims with attorneys of its own election and Lessee shall pay the cost thereof.
Nothing herein shall suggest that Lessee shall be responsible for the condition
of the Property prior to its first obtaining possession of the Premises.

     11.0 DEFAULT PROVISIONS.

     11.1 Insolvency. If, during the Term, Lessee shall be declared insolvent or
bankrupt, or if any assignment of Lessee's property shall be made for the
benefit of creditors or otherwise, or if Lessee's leasehold interest herein
shall be levied upon under execution or seized by virtue of any writ of any
court of law, or a trustee in bankruptcy or a receiver be appointed for the
property of Lessee, any such occurrence shall be a material default of this
Lease, and entitle Lessor at its election to terminate the Lease.

     11.2 Non-Payment, Breach Or Vacating. If (a) Lessee shall fail to make
payment of any rent or any charge owing

                                      -14-


<PAGE>


hereunder, or (b) any other covenant, condition, agreement or obligation of
Lessee hereunder is not timely performed and either the breach is not cured
within 15 days after written notice from Lessor or the cure of the breach is not
commenced within 15 days after written notice from Lessor and thereafter
diligently prosecuted towards completion, Lessee shall be in default and Lessor
shall be entitled to take the actions set forth in Paragraphs 11.4 and 11.5
below and Lessor may pursue any other remedy available by law.

     11.3 Default Under Other Leases. Any default under either the Building C
Lease or the Heinz Street Lease shall be deemed a default under this Lease,
entitling Lessor to take the actions set forth in Paragraphs 11.4 and 11.5 below
and Lessor may pursue any other remedy available by law.

     11.4 Lessor's Right To Relet. Upon recovery of possession of the Premises,
whether with or without legal proceedings, by reason of Lessee's breach of this
Lease, Lessor may, at its option, at any time and from time to time, remove any
signs and property of Lessee therefrom and relet the Premises or any part
thereof at such rent and upon such terms and conditions as Lessor in its
discretion shall determine, and the term of such reletting may be for a term
extending beyond the Term. Such reletting shall neither void nor terminate this
Lease. For the purpose of such reletting, Lessor is authorized to make repairs
or alterations in or to the Premises at the sole expense of Lessee as may be
necessary or desirable for the purpose of such reletting. The costs and expenses
of such reletting, including repairs and alterations and any reasonable real
estate commissions associated with such reletting shall be paid by Lessee. If a
sum shall not be realized from such reletting to equal the monthly rent payable
hereunder plus all other monthly charges to be paid by Lessee hereunder, less
any amount of rental loss for the same period which Lessee proves could be
reasonably avoided by Lessor, Lessee will pay such deficiency each month to
Lessor. In no event shall Lessor be entitled to any excess rent received by
Lessor. No re-entry, taking of possession or reletting of the Premises by Lessor
shall be construed as an election to terminate this Lease unless written notice
of such intention is given to Lessee or unless terminated thereof is decreed by
a court of competent jurisdiction.

     11.5 Right To Terminate. Notwithstanding any such reletting without
termination, Lessor may at any time during the Term elect to terminate the Lease
by reason of a previous breach. In the event that Lessor shall at any time
terminate this Lease by reason of breach thereof by Lessee, then Lessor, in
addition to any other remedy it may have, may recover from Lessee any damages
incurred by reason of such breach including, without limitation, the cost of
recovering the Premises, and the amount by which the rent then unpaid for the
balance of the Term exceeds the amount of such rental loss for the same period
which the Lessee proves could be reasonably avoided by Lessor. Lessee hereby
waives all statutory rights inconsistent with this Paragraph.

     11.6 Default By Lessor. Lessor will be in default if Lessor fails to
perform any obligation required of Lessor

                                      -15-


<PAGE>


(other than a delay in delivery of possession as provided for in Paragraph 3.2
above) within 30 days after written notice by Lessee, specifying wherein Lessor
has failed to perform such obligation; provided that if the nature of Lessor's
obligation is such that more than 30 days are required for performance, then
Lessor shall not be in default if Lessor commences performance within such 30
day period and thereafter diligently prosecutes the same to completion; and
provided further that if the performance of any obligation required by Lessor is
necessary to correct a condition that poses a threat to life or property, then
Lessor shall perform such obligation as soon as reasonably possible after
receiving written notice from Lessee, specifying that the condition is
threatening.

     12.0 EXPIRATION OR TERMINATION.

     12.1 Surrender Of Possession. Lessee agrees to deliver up and surrender to
Lessor possession of the Premises and all improvements thereon, subject to the
terms of Paragraph 7.4 above, in as good order and condition as when possession
was taken by Lessee, excepting only ordinary wear and tear. Upon termination of
this Lease, Lessor may reenter the Premises and remove all persons and property
therefrom. If Lessee shall fail to remove any effects which it is entitled to
remove from the Premises upon the termination of this Lease, for any cause
whatsoever, Lessor, at its option, may remove the same and store or dispose of
them, and Lessee agrees to pay to Lessor on demand any and all expenses incurred
in such removal and in making the Premises free from all dirt, litter, debris
and obstruction, including all storage and insurance charges. If the Premises
are not surrendered at the end of the Term, Lessee shall indemnify Lessor
against loss or liability resulting from delay by Lessee in so surrendering the
Premises, including, without limitation, any claims made by any succeeding
Lessee founded on such delay.

     12.2 Holding Over. If Lessee, with Lessor's consent, remains in possession
of the Premises after expiration of the term and if Lessor and Lessee have not
executed an express written agreement as to such holding over, then such
occupancy shall be a tenancy from month to month at a monthly rental equivalent
to 110% of the monthly rental in effect immediately prior to such expiration,
such payments to be made as herein provided. In the event of such holding over
all of the terms of this Lease including the payment of all charges owing
hereunder other than rent shall remain in force and effect on said month to
month basis.

     12.3 Voluntary Surrender. The voluntary or other surrender of this Lease by
Lessee, or a mutual cancellation thereof, shall not work a merger, but shall, at
the option of Lessor, terminate all or any existing subleases or subtenancies,
or operate as an assignment to Lessor of any or all such subleases or
subtenancies.

     13.0 CONDEMNATION OF PREMISES.

     13.1 Total Condemnation. If the entire Premises, whether by exercise of
governmental power or the sale or transfer by Lessor to any condemnor under
threat of

                                      -16-


<PAGE>


condemnation or while proceedings for condemnation are pending, at any time
during the Term, shall be taken by condemnation such that there does not remain
a portion suitable for occupation, this Lease shall then terminate as of the
date transfer of possession is required. Upon such condemnation, all rent shall
be paid up to the date transfer of possession is required, and Lessee shall have
no claim against Lessor for the value of the unexpired term of this Lease.

     13.2 Partial Condemnation. If any portion of the Premises is taken by
condemnation during the Term, whether by exercise of governmental power or the
sale or transfer by Lessor to any condemnor under threat of condemnation or
while proceedings for condemnation are pending, this Lease shall remain in full
force and effect; except that in the event a partial taking leaves the Premises
unfit for normal and proper conduct of the business of Lessee, then Lessee shall
have the right to terminate this Lease effective upon the date transfer of
possession is required. Moreover, Lessor shall have the right to terminate this
Lease effective on the date transfer of possession is required if more than 33%
of the total square footage of the Premises or the Property is taken by
condemnation. Lessee and Lessor may elect to exercise their respective rights to
terminate this Lease pursuant to this Paragraph by serving written notice to the
other within 30 days of their receipt of notice of condemnation. All rent shall
be paid up to the date of termination, and Lessee shall have no claim against
Lessor for the value of any unexpired term of this Lease. If this Lease shall
not be cancelled, the rent after such partial taking shall be that percentage of
the adjusted base rent specified herein, equal to the percentage which the
square footage of the untaken part of the Premises, immediately after the
taking, bears to the square footage of the entire Premises immediately before
the taking. Any sums owing hereunder which are calculated on the basis of
Lessee's pro rata share (as set forth in Paragraph 1.4) shall also be adjusted
to reflect the decreased square footage of the Premises due to the condemnation.
If Lessee's continued use of the Premises requires alterations and repairs by
reason of a partial taking, all such alterations and repairs shall be made by
Lessee at Lessee's expense.

     13.3 Award To Lessee. In the event of any condemnation, whether total or
partial, Lessee shall have the right to claim and recover from the condemning
authority such compensation as may be separately awarded or recoverable by
Lessee for loss of business, fixtures or equipment belonging to Lessee
immediately prior to the condemnation. The balance of any condemnation award
shall belong to Lessor and Lessee shall have no further right to recover from
Lessor or the condemning authority for any additional claims arising out of such
taking.

     14.0 ENTRY BY LESSOR.

     Lessee shall permit Lessor and its agents to enter the Premises at all
reasonable times for any of the following purposes: to inspect the Premises; to
maintain the Structural Components of the Premises; to make such repairs to the
Premises as Lessor is obligated or may elect to make; to make repairs,
alterations or additions to any other portion of the

                                      -17-


<PAGE>


Property; to show the Premises and post "To Lease" signs for the purposes of
reletting during the last 90 days of the Term; to show the Premises as part of a
prospective sale by Lessor or to post notices of nonresponsibility.
Notwithstanding the above, except in the case of emergencies, Lessor shall give
at least 24 hours prior written notice before entry to either the laboratories
or other non-office restricted areas. Lessor shall have such right of entry
without any rebate of rent to Lessee for any loss of occupancy or quiet
enjoyment of the Premises thereby occasioned.

     15.0 INDEMNIFICATION.

     Lessee agrees not to hold Lessor liable for any injury or damage, either
proximate or remote, occurring through or caused by any repairs or alterations
to the Premises, except to the extent such injury or damage arises from the
willful misconduct or negligence of Lessor. Lessee agrees that Lessor shall not
be liable for any injury or damage occasioned by defective electric wiring, or
the breaking, bursting, stoppage or leaking of any part of the plumbing, air
conditioning, heating, fire-control sprinkler systems or gas, sewer or steam
pipes, except to the extent such injury or damage arises from the willful
misconduct or negligence of Lessor. Lessee will save and hold harmless Lessor
from all loss, expense, damage or injury to persons or property arising from or
occurring by reason of its occupation or use of the Premises, except to the
extent such losses or injuries are proximately caused by any willful misconduct
or negligence of Lessor. Lessor shall not be liable for any damage to or loss of
property of Lessee or other persons located on the Premises, and Lessee shall
hold Lessor harmless from any claims arising out of damage to the same, except
to the extent such loss or damage is proximately caused by the willful
misconduct or negligence of Lessor.

     16.0 ASSIGNMENT AND SUBLETTING.

     Lessee shall not assign this Lease in whole or in part, or sublet the
Premises or any part thereof, or license the use of all or any portion of the
Premises or business conducted thereon, or encumber or hypothecate this Lease,
without first obtaining the written consent of Lessor, which consent will not be
unreasonably withheld. Lessee shall submit in writing to Lessor: (a) the name
and legal composition of the proposed sublessee; (b) the nature of the proposed
sublessee's business to be carried on in the Premises; (c) the terms and
provisions of the proposed sublease; and (d) such financial and other reasonable
information as Lessor may request concerning the proposed sublessee. Any
assignment, subletting, licensing, encumbering, or hypothecating of this Lease
without such prior written consent shall, at the option of Lessor, constitute
grounds for termination of this Lease. Lessor's consent to any assignment or
sublease shall not constitute a waiver of the necessity for such consent to any
subsequent assignment or sublease. This prohibition against assignment and
subletting shall be construed to include a prohibition against assignment or
subletting by operation of law. Notwithstanding any assignment or subletting
with Lessor's consent, Lessee shall remain fully liable on this Lease and shall
not be released from its obligations

                                      -18-


<PAGE>


hereunder. In the event Lessor shall consent to a sublease or assignment under
this Paragraph, Lessee shall pay Lessor's reasonable attorneys' fees incurred in
connection with giving such consent. In addition, Lessee shall pay to Lessor
with its regularly scheduled rent payments 75% of all sums collected by Lessee
from a sublessee or assignee which are in excess of the rent and charges then
owing to Lessor pursuant to this Lease.

     17.0 DAMAGE OR DESTRUCTION.

     17.1 Right To Terminate On Destruction Of Premises. Lessor shall have the
right to terminate this Lease if, during the Term, the Premises are damaged to
an extent exceeding 33% of the then reconstruction cost of the Premises as a
whole. Lessor shall also have the right to terminate this Lease if any portion
of the Premises is damaged by an uninsured peril. In either case, Lessor may
elect to so terminate by written notice to Lessee delivered within 30 days of
the happening of such damage.

     17.2 Repairs By Lessor. If Lessor shall not elect to terminate this Lease
pursuant to Paragraph 17.1, Lessor shall, immediately upon receipt of insurance
proceeds paid in connection with such casualty, but in no event later than 90
days after such damage has occurred, proceed to repair or rebuild the Premises,
on the same plan and design as existed immediately before such damage or
destruction occurred, subject to such delays as may be reasonably attributable
to governmental restrictions or failure to obtain materials or labor, or other
causes beyond the control of Lessor. Lessee shall be liable for the repair and
replacement of all fixtures, leasehold improvements, furnishings, merchandise,
equipment and personal property not covered by the property insurance described
in Paragraph 6.2.

     17.3 Reduction Of Rent During Repairs. In the event Lessee is able to
continue to conduct its business during the making of repairs, the rent then
prevailing will be equitably reduced in the proportion that the unusable part of
the Premises bears to the whole thereof for the period that repairs are being
made. No rent shall be payable while the Premises are wholly unusable due to
casualty damage.

     17.4 Arbitration. Any controversy or claim arising out of or relating to
this Paragraph shall be settled by arbitration in accordance with the rules of
the American Arbitration Association as then in effect, and judgment upon the
award rendered by the arbitration may be entered in any court having
jurisdiction. The expenses of arbitration shall be borne by the parties as
allocated by the arbitrators. The party desiring arbitration shall serve notice
upon the other party, together with designation of the first party's arbitrator.

     17.5 Lessor's Overriding Right To Terminate. Notwithstanding anything to
the contrary herein, if the discounted present value of the rent due hereunder
for the balance of the Term, using as the discount rate the prime commercial
lending rate in effect at the Bank of America as of the date Lessor is to
commence repairs pursuant to Paragraph

                                      -19-


<PAGE>


17.2 hereof, is less than the cost of repairing the damage to the Premises,
Lessor may at its option terminate this Lease upon 10 days' written notice.

     18.0 MISCELLANEOUS PROVISIONS.

     18.1 Waiver. No waiver of any breach of any of the covenants or conditions
of this Lease shall be construed to be a waiver of any other breach or to be a
consent to any further or succeeding breach of the same or other covenant or
condition. The subsequent acceptance of rent hereunder by Lessor shall not be
deemed to be a waiver of any preceding breach by Lessee of any term, covenant or
condition of this Lease, other than the failure of Lessee to pay the particular
rent so accepted, regardless of Lessor's knowledge of such preceding breach at
the time of acceptance of such rent.

     18.2 Successors And Assigns. Except as otherwise provided herein, the
provisions hereof shall be binding upon and shall inure to the benefit of the
heirs, personal representatives, successors and assigns of the parties.

     18.3 Notices. All notices, requests, demands and other communications
required or permitted to be given hereunder shall be in writing and either
personally delivered or sent by certified mail, return receipt requested,
postage prepaid, properly addressed to the other party at the address set forth
next to its signature below, or at such other address or addresses as may from
time to time be designated in like manner by one party to the other. Any such
notice shall be deemed given when personally delivered or on the date indicated
on the Post Office's certified mail receipt.

     18.4 Partial Invalidity. If for any reason any provision of this Lease
shall be determined to be invalid or inoperative, the validity and effect of the
other provisions hereof shall not be affected thereby.

     18.5 Number And Gender. All terms in this Lease shall be construed to mean
either the singular or the plural, masculine, feminine or neuter, as the
situation may demand.

     18.6 Descriptive Headings. The headings used herein and in any of the
documents attached hereto as schedules, lists or exhibits are descriptive only
and for the convenience of identifying provisions, and are not determinative of
the meaning or effect of any such provisions.

     18.7 Time Is Of The Essence. In all matters time is of the essence in the
performance of all obligations under this Lease.

     18.8 Entire Agreement. This Lease and the documents attached hereto as
schedules, lists or exhibits, constitute the entire agreement and understanding
between the parties with respect to the subject matters herein and therein, and
supersede and replace any prior agreements and understandings, whether oral or
written, between and among them with respect to the lease of the Premises,
rental therefor, use thereof and all other such matters. The provisions of this
Lease may be

                                      -20-


<PAGE>


waived, altered, amended or repealed in whole or in part only upon the written
consent of Lessor and Lessee.

     18.9 Memorandum Of Lease. Lessor and Lessee mutually agree that they will
not file or record a copy of this Lease, but that in the event Lessor or Lessee
requests a recording, Lessor and Lessee shall execute and acknowledge a
memorandum of this Lease in a form approved by the parties setting forth in said
memorandum the description of the Premises, the date of the Lease, the
Commencement Date and the date of termination. Said memorandum of Lease may be
recorded in the Recorder's Office of the County in which the Premises are
located.

     18.10 Applicable Law. This Lease Agreement shall be construed and
interpreted in accordance with the laws of the State of California.

     18.11 Corporate Authority. Each individual executing this Lease on behalf
of a corporation represents and warrants that he is duly authorized to execute
and deliver this Lease on behalf of the corporation in accordance with a duly
adopted resolution of the Board of Directors of the corporation, and that this
Lease is binding upon said corporation in accordance with its terms.

     18.12 Litigation Expense. If any party shall bring an action against any
other party hereto by reason of the breach of any covenant, warranty,
representation or condition hereof, or otherwise arising out of this Agreement
or any schedule list or exhibit hereto, whether for declaratory or other relief,
the prevailing party in such suit shall be entitled to such party's costs of
suit and attorneys' fees, which shall be payable whether or not such action is
prosecuted to judgment.

     18.13 Subordination Of Leasehold. Lessee agrees that this Lease is and
shall be, at all times, subject and subordinate to the lien of any mortgage or
other encumbrances which Lessor may create against the Premises including all
renewals, replacements and extensions thereof; provided, however, that
regardless of any default under any such mortgage or encumbrance or any sale of
the Premises under such mortgage, so long as Lessee performs all covenants and
conditions of this Lease and continues to make all payments hereunder, this
Lease and Lessee's possession and rights hereunder shall not be disturbed by the
mortgagees or anyone claiming under or through such mortgages. Lessee agrees to
execute any and all instruments in writing which may be required by Lessor to
subordinate Lessee's rights to the lien of such mortgage.

     18.14 Lessee's Certificate. Within 15 days following Lessor's request,
Lessee shall complete, execute and deliver to Lessor a Lessee's Certificate,
setting forth the information requested therein including, but not limited to
(a) certification that this Lease is unmodified and in full force and effect (or
if modified, stating the nature of such modification and certifying that this
Lease as so modified is in full force and effect) and the date to which the
rental and other charges are paid in advance, if any, (b) acknowledgement that
there are not, to Lessee's knowledge, any uncured defaults

                                      -21-


<PAGE>


on the part of Lessor hereunder, or specifying such defaults if any are claimed
and (c) setting forth the date of commencement and expiration of the Term.
Failure of Lessee to deliver such Certificate within said 15 days shall be
deemed to be an acknowledgement that Lessor is not in default under the Lease,
and that the terms of the Lease have not been modified or supplemented in any
way. It is intended that such Certificate may be relied upon by any prospective
purchaser, lender or assignee of any lender of the Premises.

     18.15 Attornment. Lessee shall, in the event of any sale of the Premises or
if proceedings are brought for the foreclosure of, or in the event of exercise
of the power of sale under, any mortgage, installment land contract or deed of
trust made by Lessor covering the Premises, attorn to the mortgagee or the
purchaser upon any such foreclosure or sale and recognize such mortgagee or
purchaser as Lessor under this Lease, provided that Lessee's possession and
rights hereunder shall not be disturbed by the mortgagee or purchaser.

     18.16 Day. As used herein, the term "day" shall mean, unless otherwise
specifically stated, a calendar day.

     18.17 Brokers. The only broker's fees in connection with this Lease shall
be payable by Lessor to Coldwell Banker. Each party hereby indemnifies and
agrees to hold the other harmless from any and all other broker fees.

     IN WITNESS WHEREOF, the parties have executed this Lease on the day and
year first written above.


LESSOR:                                 LESSEE:

SEVENTH STREET PROPERTIES II            XOMA CORPORATION
1120 Nye Street, Suite 400              _______________________________
San Rafael, CA  94915                   _______________________________
                                                 (Address)

By  /s/ Richard K. Robbins              By /s/ Steven C. Mendell
- ----------------------------               -----------------------------
(Signature)                                     (Signature)

Richard K. Robbins                      Steven C. Mendell/ CEO
- ----------------------------            --------------------------------
(Print Name & Title)                    (Print Name & Title)

                                      -22-


<PAGE>


                                    EXHIBIT A

                      DESCRIPTION OF PREMISES AND PROPERTY

                       (Drawing of Premises appears here)











                                      -23-


<PAGE>


                                    EXHIBIT B

                WORK TO BE PERFORMED BEFORE OCCUPANCY OF PREMISES

     Lessor shall deliver the Premises to Lessee in shell condition. As used
herein, "shell condition" shall mean that the Premises shall include all of the
following: exterior walls with windows and doors, roof structure and roofing,
concrete slab on the first floor and wood floors on the second floor, elevator
with equipment room, two stairs and exit enclosures, exterior painting, fire
sprinklers (one layer below roof structure and second layer below wood floor),
roof drainage, standard building utilities brought to the Premises but not
distributed, male and female toilets on the first and second floors,
landscaping, recessed and covered loading dock with drainage and roll-up door,
parking lot, storm sewers, sidewalks, electrical secondary cable and conduit,
site lighting, roof hatch and ladder, rock below slab, finished lobby area on
the first floor and finished core areas on the second floor. The parties
recognize that Lessor shall incur additional costs in constructing the shell of
the Premises due to Lessee's desire to utilize some of the Premises for
laboratory purposes; specifically, there will be substantially increased
interstitial space required in the Premises than is typical in a two story
office building. The increased costs of the construction and the working
drawings as a result of the interstitial space shall be the responsibility of
Lessee. The increased costs of the interstitial space shall be designated as
such by the contractor and/or architect, as the case may be, and Lessor shall
forward to Lessee a copy of such designations. Any dispute as to the computation
of the increased costs shall be settled by arbitration in the same manner as
Paragraph 17.4 of this Lease. All such increased costs to Lessor (the "Increased
Costs") shall be deducted from the Allowance paid to Lessee, as set forth below.

     Lessee shall construct all tenant improvements to be placed on the Premises
in accordance with the working drawings approved in writing by Lessor. Lessee
shall be entitled to an allowance of $21.00 per square foot of leaseable space
(the "Allowance") for the construction of the tenant improvements and the
preparation of the working drawings therefor. If the cost of the tenant
improvements exceeds the Allowance, such excess shall be borne by Lessee, at its
own expense. The Allowance, less the Increased Costs, shall be paid to Lessee in
cash within 15 days of occupancy of the Premises by Lessee and approval of the
tenant improvements by Lessor.

                                     - 24 -


                                                                   June 26, 1987

Mr. Ho Humphrey
Xoma Corporation
2910 Seventh Street
Berkeley, CA 94710

                     RE: BUILDING C OF AQUATIC PARK CENTER.

Dear Mr. Humphrey:

     On or about the date of this letter, Xoma Corporation ("Xoma") and Seventh
Street Properties II ("Lessor") entered into a lease of Building C at Aquatic
Park Center (the "Lease").

     With respect to Building C, the parties hereby agree as follows:

     Xoma shall have the right of first refusal to purchase Building C from
Lessor if and when Lessor elects to sell its entire interest in Building C. If
Lessor proposes to sell the Building, it shall first serve written notice on
Xoma setting forth the terms on which Building C shall be sold (the "Initial
Notice"). Xoma shall have 15 calendar days after receipt of the Initial Notice
in which to inform Lessor in writing that it wishes to purchase the Building on
the terms set forth in the Initial Notice. Notices shall be delivered in
accordance with the terms of the Lease. Failure of Xoma to serve such written
notice within the 15 day period or to close the sale within 45 days after
serving notice on Lessor of its intent to purchase (other than as a result of
Lessor's default) shall be deemed to be a waiver of its right of first refusal,
and Lessor shall be free thereafter to sell Building C to third parties.
Notwithstanding the above, if Lessor proposes to offer more favorable terms to
third parties than set forth in the Initial Notice, then Lessor shall serve
another written notice on Xoma and again go through the procedure set forth
above, provided that Lessor shall not need to serve another written notice or go
through the procedure if Xoma had previously elected to purchase Building C but
failed to close the transaction within the time stated above.
<PAGE>
Mr. Ho Humphrey
June 26, 1987
Page 2

     Please confirm by signing below your agreement with this amendment to the
Lease and your acknowledgment that except for this specific amendment, all terms
and conditions of the Lease shall remain unmodified and in full force and
effect.

                                  Sincerely,

                                  SEVENTH STREET PROPERTIES II

                                  By /s/ Richard K. Robbins
                                         (Signature)
                                      (Print Name And Title)

The terms set forth above are hereby agreed to on 8/26, 1987.

XOMA CORPORATION

By /s/ Steven C. Mendell
(Signature)
Chairman/ CEO
(Print Name & Title)
<PAGE>
                                XOMA CORPORATION

                                   BUILDING C

                           TRIPLE NET LABORATORY LEASE

                                Table Of Contents
Paragraph         Title                                                 Page

1.0               BASIC LEASE TERMS                                     1

                  1.1        Commencement Of Lease                      1
                  1.2        Lease Term                                 1
                  1.3        Monthly Rent                               1
                  1.4        Lessee's Pro Rata Share                    1
                  1.5        Security Deposit                           1
                  1.6        Use                                        1

2.0               PREMISES   2

                  2.1        Description                                2
                  2.2        Work Of Improvement                        2
                  2.3        Possession                                 2

3.0               TERM                                                  2

                  3.1        Commencement                               2
                  3.2        Delay In Commencement                      2
                  3.3        Option To Terminate                        2
                  3.4        Option To Extend Term                      2
                  3.5        Term                                       3
                  3.6        Fair Market Lease Rate                     3

4.0               RENT                                                  4

                  4.1        Monthly Rent                               4
                  4.2        Rent Adjustment                            4
                  4.3        Mode Of Payment                            5
                  4.4        Triple Net Lease                           5
                  4.5        Estimated Payments                         5
                  4.6        Security Deposit                           6
                  4.7        Late Charges                               6

5.0               TAXES                                                 7

                  5.1        Real Property Taxes                        7
                  5.2        Personal Property Taxes                    7

6.0               INSURANCE  8

                  6.1        Property/Rental Insurance -
                             Premises                                   8
                  6.2        Property Insurance - Fixtures And
                             Inventory                                  8
                  6.3        Lessor's Liability Insurance               8
                  6.4        Lessee's Liability Insurance               8
                  6.5        Waiver Of Subrogation                      9

                                       -i-
<PAGE>
                  6.6        Indemnification                            9
                  6.7        Plate Glass Replacement                    9
                  6.8        Workers' Compensation Insurance            10

7.0               MAINTENANCE                                           10

                  7.1        Premises                                   10
                  7.2        Building                                   10
                  7.3        Common Areas                               11
                  7.4        Alterations, Changes And Additions
                             By Lessee                                  11
                  7.5        Plumbing                                   11
                  7.6        Liens                                      12

8.0               MANAGEMENT 12

9.0               UTILITIES AND SERVICES                                12

                  9.1        Premises                                   12
                  9.2        Common Areas                               12

10.0              USE OF PREMISES                                       13

                  10.1       Use                                        13
                  10.2       Suitability                                13
                  10.3       Uses Prohibited                            13
                  10.4       Lessee's Warranty                          14

11.0              DEFAULT PROVISIONS                                    14

                  11.1       Insolvency                                 14
                  11.2       Non-Payment, Breach Or Vacating            15
                  11.3       Default Under Other Leases                 15
                  11.4       Lessor's Right To Relet                    15
                  11.5       Right To Terminate                         15
                  11.6       Default By Lessor                          16

12.0              EXPIRATION OR TERMINATION                             16

                  12.1       Surrender Of Possession                    16
                  12.2       Holding Over                               16
                  12.3       Voluntary Surrender                        16

13.0              CONDEMNATION OF PREMISES                              17

                  13.1       Total Condemnation                         17
                  13.2       Partial Condemnation                       17
                  13.3       Award To Lessee                            17

14.0              ENTRY BY LESSOR                                       18

15.0              INDEMNIFICATION                                       18

16.0              ASSIGNMENT AND SUBLETTING                             18

17.0              DAMAGE OR DESTRUCTION                                 19

                  17.1       Right To Termination On Destruction
                             Of Premises                                19
                  17.2       Repairs By Lessor                          19

                                      -ii-
<PAGE>
                  17.3       Reduction Of Rent During Repairs           l9
                  17.4       Arbitration                                l9
                  17.5       Lessors Overriding Right To
                             Terminate                                  20

18.0              MISCELLANEOUS PROVISIONS                              20

                  18.1       Waiver                                     20
                  18.2       Successors And Assigns                     20
                  18.3       Notices                                    20
                  18.4       Partial Invalidity                         20
                  18.5       Number And Gender                          20
                  18.6       Descriptive Headings                       20
                  18.7       Time Is Of The Essence                     20
                  18.8       Entire Agreement                           21
                  18.9       Memorandum Of Lease                        21
                  18.10      Applicable Law                              21
                  18.11      Corporate Authority                        21
                  18.12      Litigation Expense                         21
                  18.13      Subordination Of Leasehold                 21
                  18.14      Lessee's Certificate                       21
                  18.15      Attornment                                 22
                  18.16      Day                                        22
                  18.17      Brokers                                    22

EXHIBIT A - DESCRIPTION OF THE PREMISES AND PROPERTY
EXHIBIT B - WORK TO BE PERFORMED BEFORE OCCUPANCY OF PREMISES

                                      -iii-
<PAGE>
                                XOMA CORPORATION

                                   BUILDING C

                                TRIPLE NET LEASE

     LEASE made and entered into this 22 day of July 1987, between SEVENTH
STREET PROPERTIES II ("Lessor") and XOMA CORPORATION ("Lessee").

                                R E C I T A L S:

     A. Concurrently with the execution of this Lease, Lessee is entering into
three other leases, specifically one with Lessor for approximately 35,000 square
feet in Building E at Aquatic Park Center (the "Building E Lease") another with
Lessor for approximately 20,000 square feet in Building F at Aquatic Park Center
(the "Building F Lease"), and another with Seventh Street Properties, an
affiliate of Lessor, for approximately 24,275 square feet at 890 Heinz Street,
Berkeley, California (the "Heinz Street Lease").

     B. The Building E Lease, the Heinz Street Lease and this Lease are intended
to be read together so that a breach of one is deemed a breach of the other.

                               A G R E E M E N T:

     NOW, THEREFORE, the parties hereby agree as follows:

     1.0 BASIC LEASE TERMS.

     1.1 Commencement Of Lease: The term of this Lease shall commence on the
earlier of:

     a. The date Lessor notifies Lessee in writing that the construction to be
performed by Lessor pursuant to Paragraph 2.2 hereof has been substantially
completed. Substantial completion shall occur when the Premises are in such
condition as to permit Lessor to file a Notice of Completion with respect to its
work; or

     b. The date Lessee actually commences to do business at the Premises.

     1.2 Lease Term: Through April 30, 2003.

     1.3 Monthly Rent: $6,384.

     1.4 Lessee's Pro Rata Share: 5.6%.

     1.5 Security Deposit: $7,056.

     1.6 Use: Pharmaceutical manufacturing, offices, laboratories, shipping and
receiving relating to pharmaceutical products.

                                      -1-
<PAGE>
     2.0 PREMISES.

     2.1 Description. Lessor hereby leases to Lessee a portion of Building C
(the "Premises") constituting approximately 6,720 square feet, which constitute
a portion of a larger piece of real property owned by Lessor and known as the
Aquatic Park Center (the "Property"). Exhibit A attached hereto further
describes the Premises and the Property.

     2.2 Work Of Improvement. The respective obligations of Lessor and Lessee to
perform the work and supply material and labor to prepare the Premises for
occupancy are set forth in Exhibit B attached hereto and incorporated herein.
Lessor and Lessee shall expend all funds and do all acts required of them
respectively in Exhibit B and shall have the work performed promptly and
diligently in a first-class, workmanlike manner. Lessee shall not commence
construction of the improvements to be undertaken by Lessee until Lessor has
approved in writing the final drawings for said improvements, which approval
shall neither be unreasonably withheld nor delayed.

     2.3 Possession. Lessor shall deliver occupancy of the Premises to Lessee on
the Commencement Date as hereinafter defined.

     3.0 TERM.

     3.1 Commencement. The Lease shall commence on the date specified in
Paragraph 1.1 above (the "Commencement Date") and shall continue thereafter for
the term specified in Paragraph 1.2 above (the "Initial Term"), unless sooner
terminated pursuant to this Lease.

     3.2 Delay In Commencement. If for any reason Lessor cannot deliver
possession of the Premises to Lessee on the Commencement Date, such failure
shall not affect the validity of this Lease nor shall it extend the Term or
render Lessor liable to Lessee for any loss or damage resulting therefrom;
except that if possession is not delivered to Lessee on the Commencement Date,
Tenant shall not be obligated to pay rent until possession of the Premises is
tendered to Lessee. Notwithstanding the above, if Lessor does not deliver
possession of the Premises to Lessee by June 30, 1988, then Lessee shall have
the option of terminating this Lease by serving written notice on Lessor on or
before July 15, 1988.

     3.3 Option To Terminate. Lessee is hereby granted an option to terminate
the Lease effective April 30, 1998 by giving written notice to Lessor of
Lessee's intent to terminate (the "Termination Notice") on or before July 31,
1997.

     3.4 Option To Extend Term. Lessee is hereby granted an option to extend the
term for a five year period following the expiration of the Initial Term (the
"Option Term") by giving written notice to the Lessor of Lessee's intent to
exercise such option (the "Option Notice") at least 270 days before the
expiration of the Initial Term. The Option Term shall be on the same terms and
conditions in effect immediately before the end of the Initial Term, except that
the rent shall

                                       -2-
<PAGE>
be set at 95% of the fair market lease rate for comparable space in the Berkeley
area, provided that in no event shall the rental rate for the Option Term be
less than the rental rate as of the last day of the Initial Term.
Notwithstanding anything to the contrary above, if Lessee is in default in the
payment of rent, in the making of other payments required to be made by Lessee
under this lease, or otherwise under this Lease on the date the Option Notice is
delivered to Lessor or on the date the Option Term is to commence, the Option
Term shall not commence and this Lease shall expire at the end of the Initial
Term.

     3.5 Term. All references to the "Term" in this Lease shall include the
Initial Term set forth in Paragraph 3.1 plus any extensions pursuant to
Paragraph 3.4.

     3.6 Fair Market Lease Rate. Lessor shall give Lessee notice ("Lessor's
Notice") of the fair market lease rate after receiving Lessee's written notice
of intent to exercise the Option, provided that Lessor's Notice shall not be
delivered later than 120 days prior to the commencement of the Option Term. If
Lessee believes that the fair market lease rate as established by Lessor is
incorrect, Lessee shall notify Lessor in writing within 20 days of Lessee's
receipt of the notice from Lessor that Lessee desires to submit the matter to
appraisal with a designation of an MAI qualified appraiser. If Lessor agrees
with the identity of such appraiser, it shall within 10 days notify the
appraiser and Lessee that such appraiser shall determine the fair market lease
rate (including fair market increases during the Option Term). If not, Lessor
shall submit the name of its appraiser to Lessee within said 10 days. The two
appraisers so selected shall choose a third appraiser and the three together
shall determine the fair market lease rate (including fair market increases
during the Option Term). If the two appraisers cannot select a third appraiser
within 20 days after Lessor submits the name of its appraiser, either party may
at any time apply to the presiding judge of any court of competent jurisdiction
for the appointment of the third appraiser. If the three appraisers are unable
to agree on the fair market lease rate they shall each determine the fair market
lease rate assuming annual CPI increases during the Option Term and then average
their determinations by tossing out the high and low appraisal and accepting the
middle appraisal as the fair market lease rate. The costs of the appraisal
process shall be borne by Lessee unless the fair market lease rate as determined
by the appraisal is more than 10% below the lease rate set forth in Lessor's
Notice in which case Lessor and Lessee shall share the costs of the appraisal
process equally. The appraisal process shall be completed as quickly as
reasonably possible. If for any reason the Option Term commences prior to the
conclusion of the appraisal process, Lessee shall continue to pay the monthly
base rent then in effect to Lessor plus 10% of such amount, which 10% only shall
be held by Lessor in escrow pending completion of the appraisal process, at
which time all funds held in escrow shall be distributed to Lessee and/or Lessor
in accordance with the outcome of the appraisal process, and Lessee shall
subsequently be bound by the lease rate as determined by the appraisal process.
The rent during the Option Term shall continue to be adjusted as agreed upon

                                       -3-
<PAGE>
between Lessor and Lessee or as determined by the appraisal process.

     4.0 RENT

     4.1 Monthly Rent. Lessee shall pay to Lessor as rent for the Premises in
advance on the first day of each calendar month of the Term without deduction,
offset, prior notice or demand, in lawful money of the United States, the sum
specified in Paragraph 1.3 above which is based on $.95 per square foot and the
square footage set forth in Paragraph 2.1. The rent owing shall be adjusted as
necessary if the actual square footage is shown to be other than as set forth in
Paragraph 2.1. Notwithstanding the above, Lessee shall not be required to pay
rent until the Commencement Date under the Building E Lease. If the Commencement
Date is not the first day of a calendar month, the first monthly installment of
such rent shall be applied on a per diem basis against payment of the rent from
the Commencement Date until the first day of the first succeeding calendar
month. Any unused portion of said amount shall be applied against payment of the
rent for such first succeeding calendar month, and the balance of the rent for
that month shall be due on the first day thereof. Concurrent with Lessee's
execution of this Lease, Lessee shall pay to Lessor the first monthly
installment of rent.

     4.2 Rent Adjustment. The base rent shall be adjusted on the one year
anniversary of the Commencement Date to $1.05 per square foot. Thereafter, for
the period through April 30, 1998 the base rent of $1.05 per square foot shall
be adjusted as follows. On October 1, 1990 and every three years thereafter (the
"Adjustment Dates"), the base rent shall be adjusted by the percentage increase
in the Consumer Price Index (all items) for all urban consumers in the San
Francisco-Oakland metropolitan area, published by the United States Department
of Labor, Bureau of Labor Statistics. The monthly rent until the next Adjustment
Date shall be the greater of (a) the rent in effect immediately before the
Adjustment Date or (b) the rent of $1.05 per square foot multiplied by a
fraction, the numerator of which shall be said Index number for the calendar
month three months prior to the Adjustment Date and the denominator of which
shall be said Index number for the calendar month three months prior to the
first full calendar month following the Commencement Date. Notwithstanding the
above, in no case shall the increase as of any Adjustment Date exceed 21% plus
the Carry Forward. As used above, the "Carry Forward" shall mean the percentage
increases in CPI which are not used at earlier Adjustment Dates to adjust the
rent because of this limitation. For example, if the CPI increase is 15% on
October 1, 1990, then the Carry Forward is six percent and the CPI increase on
October 1, 1993 shall be the actual CPI increase, not to exceed 27%. If the
actual CPI increase on October 1, 1993 were 23%, then the Carry Forward to
October 1, 1996 would be four percent. Should the Bureau discontinue the
publication of said Index numbers, or publish the same less frequently, or alter
the same in some other manner, then Lessor shall adopt a substitute index or
procedure which reasonably reflects consumer prices. Commencing May 1,

                                       -4-
<PAGE>
1998, the adjustment mechanism set forth above shall be discarded and rent shall
be adjusted to 95% of the fair market lease rate as of May 1, 1998 for
comparable space in the Berkeley area, provided that in no event shall the new
rental rate be less than the rental rate in effect immediately before such
adjustment. (Adjustments subsequent to May 1, 1998 shall be determined in the
course of establishing the fair market lease rate.) On or before January 1,
1998, Lessor shall provide Lessee with notice of the May 1, 1998 fair market
lease rate. The fair market lease rate shall then be determined in accordance
with Paragraph 3.6, and the notice referenced above shall be deemed "Lessor's
Notice."

     4.3 Mode Of Payment. Lessee shall pay all rent due Lessor at Lessor's
address set forth on the signature page hereof, or any such other place as
Lessor may designate from time to time in writing.

     4.4 Triple Net Lease. This Lease is what is commonly called a "Net, Net,
Net Lease," it being understood that Lessor shall receive the rent set forth
herein free and clear of any and all other impositions, taxes, liens, charges or
expenses of any nature whatsoever in connection with the ownership and operation
of the Premises. All references herein to Lessee's pro rata share of any expense
shall mean the total expense of any such item multiplied by a fraction, the
numerator of which shall be the total floor area of the Premises and the
denominator of which shall be the total floor area available for lease by Lessor
of Buildings C, E and F on the Property. "Floor area" shall be measured from the
exterior surface of all exterior walls and from the center of all walls
separating the Premises from adjacent premises. Based upon the square footage
numbers set forth in Paragraph 2.1, Lessee's pro rata share has been calculated
and is set forth in Paragraph 1.4. Lessee's pro rata share shall be adjusted as
necessary if the actual square footage is shown to be other than as set forth in
Paragraph 2.1 or upon any subdivision of the Property. In the event of
non-payment of all or any portion of such charges, costs and expenses, Lessor
shall have the same rights and remedies as provided in this Lease for failure of
Lessee to pay rent. Lessee shall in no event be entitled to any abatement or
reduction of rent or other monetary sums payable hereunder, except as expressly
provided herein, notwithstanding any present or future law to the contrary.

     4.5 Estimated Payments. Lessee shall be notified by Lessor of Estimated
Payments for taxes, insurance, maintenance of common areas and common area
utilities and services from time to time. The Estimated Payments shall be paid
by Lessee together with rent, on the first day of each month throughout the
Term. The Estimated Payments may be increased or decreased by Lessor upon 30
days' written notice to Lessee based upon statements received or charges
incurred by Lessor, information available to Lessor as to the probable cost of
expected charges and expenses, or the reasonable estimate of Lessor as to the
probable amount of expected charges or expenses. Lessor shall be entitled to
retain the monies received from such payments in its general fund pending
payment of all such costs and charges. No more frequently than once each
calendar quarter, the actual costs shall be determined by Lessor, and Lessee
shall remit to Lessor on demand its unpaid pro rata share of

                                       -5-
<PAGE>
the actual expense. In the event Lessee paid more than its pro rata share of the
actual expenses for such period of time, Lessor shall apply such overpayment
towards the next Estimated Payments owing by Lessee. At the termination of this
Lease, an accounting for such charges and expenses shall be made to the nearest
practical accounting period, and Lessee shall pay to Lessor any balance due, or
the Lessor shall refund to Lessee any excess amount paid.

     4.6 Security Deposit. Concurrent with Lessee's execution of this Lease,
Lessee shall deposit with Lessor as a security deposit the sum specified in
Paragraph 1.5 above (the "Deposit"). On May 1, 1998 and May 1, 2003 (unless the
Lease is terminated or the Option is not exercised, as the case may be) Lessee
shall increase the Deposit to that amount which is equal to the newly
established monthly rental. The Deposit shall be held by Lessor as a security
deposit for the faithful performance by Lessee of all terms, covenants, and
conditions of this Lease to be kept and performed by Lessee during the Term. If
Lessee defaults with respect to any provisions of this Lease, including but not
limited to the provisions relating to the payment of rent and any of the
monetary sums due hereunder, Lessor may (but shall not be required to) use,
apply or retain any part or all of the Deposit for the payment of any amount
which Lessor may spend or become obligated to spend by reason of Lessee's
default or to compensate Lessor for any loss or damage which Lessor may suffer
by reason of Lessee's default. If any portion of the Deposit is so used or
applied, Lessee shall, within 10 days after written demand therefor, deposit
cash with Lessor in an amount sufficient to restore the Deposit to its original
amount; Lessee's failure to do so shall be a material breach of this Lease.
Lessor shall not be required to keep the Deposit separate from its general
funds, and Lessee shall not be entitled to interest on the Deposit. If Lessee
shall fully and faithfully perform every provision of this Lease to be performed
by it, the Deposit or any balance thereof shall be returned to Lessee (or, at
Lessor's option, to the last assignee of Lessee's interests hereunder) at the
expiration of the Term and after Lessee has vacated the Premises. In the event
of termination of Lessor's interest in this Lease, Lessor shall transfer the
Deposit to Lessor's successor in interest, whereupon Lessee agrees to release
Lessor from all liability for the return of the Deposit or the accounting
therefor.

     4.7 Late Charges. Lessee hereby acknowledges that late payment by Lessee to
Lessor of rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this Lease, the exact amount of which will be extremely
difficult to ascertain. Such costs include, but are not limited to, processing
and accounting charges, and late charges which may be imposed on the Lessor by
the terms of any mortgage or trust deed covering the Premises. Accordingly, if
any installment of rent or any other sum due from Lessee shall not be received
by Lessor or Lessor's designee within 10 days after such amount shall be due,
Lessee shall pay to Lessor a late charge equal to five percent of such overdue
amount. The parties hereby agree that such late charge represents a fair and
reasonable estimate of the costs Lessor will incur by reason of late payment by
Lessee. Acceptance of such late

                                       -6-
<PAGE>
charge by Lessor shall in no event constitute a waiver of Lessee's default with
respect to such overdue amount, nor prevent a Lessor from exercising any of the
other rights and remedies granted hereunder.

     5.0 TAXES.

     5.1 Real Property Taxes. Lessee agrees to pay to Lessor in addition to the
rent and other charges herein its pro rata share of all Designated Real Property
Taxes in accordance with Paragraph 4.5. As used herein, "Real Property Taxes"
shall include any form of assessment, license, fee, rent, tax, levy, penalty or
tax imposed by any authority having the direct or indirect power to tax,
including any improvement district, as against any legal or equitable interest
of Lessor in the Property or as against Lessor's business of renting the
Property. As used herein, "Designated Real Property Taxes" shall mean all Real
Property Taxes except those Real Property Taxes which are shown on the tax bill
for the Property as applying to the improvements constituting Buildings A and B,
as shown on Exhibit B, and 86.82% of (a) the Real Property Taxes applying to the
land and (b) special assessments against the Property. Such percentage was
determined by comparing the square footage of all of the land within the
Property to the square footage of all such land not occupied by Buildings A and
B, plus 14,000 square feet of the Property attributed to Buildings A and B.
Lessee's share of Designated Real Property Taxes shall be equitably prorated to
cover only the period of time within the fiscal tax year during which this Lease
is in effect. With respect to any assessments which may be levied against or
upon the Premises, and which may be paid in annual installments, only the amount
of such annual installments (with appropriate proration for any partial year)
and interest due thereon shall be included within the computation of the annual
Designated Real Property Taxes. Lessor represents that, to the best of its
knowledge, there are no assessment or improvement districts being planned which
would affect the Property other than as in effect as of the date of this Lease.
If the Property becomes subdivided, the formulas above shall continue to apply
(unless Building E is split off into a separate parcel without any other
buildings) but Lessee's pro rata share and the percentage shown above shall be
adjusted to reflect the new square footage of the resulting parcels. If Building
E is split off from the Property into a separate parcel without any other
buildings, it shall be assessed by itself and Lessee shall be responsible for
all of the Real Property Taxes relating thereto.

     5.2 Personal Property Taxes. Lessee shall pay before delinquency all taxes
levied or assessed on Lessee's fixtures, improvements, furnishings, merchandise,
equipment and personal property in and on the Premises, whether or not affixed
to the real property. If Lessee in good faith contests the validity of any such
personal property taxes, then Lessee shall at its sole expense defend itself and
Lessor against the same and shall pay and satisfy any adverse determination or
judgment that may be rendered thereon and shall furnish Lessor with a surety
bond satisfactory to Lessor in an amount equal to 150% of such contested taxes.
Lessee shall indemnify Lessor against liability for any such taxes and/or any
liens placed on

                                       -7-
<PAGE>
the Premises or the Property in connection with such taxes. If at any time after
any tax or assessment has become due or payable Lessee or its legal
representative neglects to pay such tax or assessment, Lessor shall be entitled,
but not obligated, to pay the same at any time thereafter and such amount so
paid by Lessor shall be repaid by Lessee to Lessor with Lessee's next rent
installment together with interest at the highest rate allowable by law.

     6.0 INSURANCE.

     6.1 Property/Rental Insurance - Premises. During the Term, Lessor shall
keep the Property insured against loss or damage by fire and those risks
normally included in the term "all risk" including (a) flood coverage at the
election of Lessor, (b) earthquake coverage at the reasonable election of
Lessor, (c) coverage for loss of rents and (d) boiler and machinery coverage if
the Lessor deems necessary. Any deductibles shall be paid by Lessee if the
deductible arises from damage solely to the Premises. If the damage covers a
greater portion of the Property than the Premises, then Lessee shall pay that
portion of the deductible which the total floor area of the Premises bears to
the total floor area of the Property which is available for lease by Lessor and
which suffered damage. The amount of such insurance shall be not less than 100%
of the replacement value of the Premises. Any recovery received from said
insurance policy shall be paid to Lessor. Lessee, in addition to the rent and
other charges provided herein, agrees to pay to Lessor its pro rata share of the
premiums for all insurance for the Property, excluding that insurance applicable
to Buildings A and B as shown by the insurance company (or its broker) issuing
such insurance. The insurance premiums shall be paid in accordance with
Paragraph 4.5. Lessee shall pay to Lessor any deductibles owing within 15 days
after receipt of notice from Lessor of the amount owing.

     6.2 Property Insurance - Fixtures And Inventory. During the Term, Lessee
shall, at its sole expense, maintain insurance with "all risk" coverage on any
fixtures, leasehold improvements, furnishings, merchandise, equipment or
personal property in or on the Premises, whether in place as of the date hereof
or installed hereafter, for the full replacement value thereof, and Lessee shall
also have sole responsibility and cost for maintaining any other types of
insurance relating to Lessee's use of the Premises. Any deductibles shall be
paid by Lessee.

     6.3 Lessor's Liability Insurance. During the Term, Lessor shall maintain a
policy or policies of comprehensive general liability insurance insuring Lessor
(and such others as designated by Lessor) against liability for bodily injury,
death and property damage on or about the Property, with combined single limit
coverage of not less than $2,000,000.

     6.4 Lessee's Liability Insurance. During the Term, Lessee shall, at its
sole expense, maintain for the mutual benefit of Lessor and Lessee,
comprehensive general liability and property damage insurance against claims for
bodily injury, death or property damage occurring in or about the Premises or
arising out of the use or occupancy of the Premises, with

                                       -8-
<PAGE>
combined single limit coverage of not less than $2,000,000. The limits of such
insurance shall not limit the liability of Lessee. Lessee shall furnish to
Lessor prior to the Commencement Date, and at least 30 days prior to the
expiration date of any policy, certificates indicating that the liability
insurance required by Lessee above is in full force and effect, that Lessor has
been named as an additional insured; and that all such policies will not be
cancelled unless 30 days' prior written notice of the proposed cancellation has
been given to Lessor. The insurance shall be with insurers reasonably approved
by Lessor and with policies in form reasonably satisfactory to Lessor. Said
policies shall provide that Lessor, although an additional insured, may recover
for any loss suffered by Lessor by reason of Lessee's negligence, and shall
include a broadform liability endorsement.

     6.5 Waiver Of Subrogation. Lessor hereby releases Lessee, and Lessee hereby
releases Lessor, and their respective officers, agents, employees and servants,
from any and all claims or demands of damages, loss, expense or injury to the
Premises, or to the furnishings and fixtures and equipment, or inventory or
other property of either Lessor or Lessee in, about or upon the Premises, which
is caused by or results from perils, events or happenings which are the subject
of insurance carried by the respective parties and in force at the time of any
such loss; provided, however, that such waiver shall be effective only to the
extent permitted by the insurance covering such loss and to the extent such
insurance is not prejudiced thereby. Each party shall cause each insurance
policy obtained by it to provide that the insurance company waives all right of
recovery by way of subrogation against either party in connection with any
damage covered by any policy.

     6.6 Indemnification. Except to the extent of intentional misconduct by
Lessor or Lessor's negligence, Lessee will indemnify Lessor and save it harmless
from and against any and all claims, actions, damages, liability and expense in
connection with loss of life, personal injury and/or damage to property arising
from or out of any occurrence in, upon or at the Premises, or the occupancy or
use by Lessee of the Premises or any part thereof, or occasioned wholly or in
part by any acts or omissions of Lessee, its agents, contractors, employees,
servants, licensees or concessionaires or by anyone permitted to be on the
Premises by Lessee. In case Lessor shall be made a party to any such litigation
commenced by or against Lessee, then Lessee shall protect and hold Lessor
harmless from all claims, liabilities, costs and expenses, and shall pay all
costs, expenses and reasonable legal fees incurred by Lessor in connection with
such litigation.

     6.7 Plate Glass Replacement. Lessee shall replace at its sole expense, any
and all plate glass and other glass in and about the Premises which is damaged
or broken by vandalism. If any plate glass or other glass in and about the
Premises is damaged or broken by causes other than vandalism, then Lessee shall
pay Lessor an amount equal to Lessor's cost of replacement, provided that such
amount shall not exceed the deductible then in effect on Lessor's insurance
policy, if any, covering the damaged glass. Nothing herein shall be construed to
require Lessor to carry plate glass insurance.

                                       -9-
<PAGE>
     6.8 Workers' Compensation Insurance. Lessee shall, at its sole expense,
maintain and keep in force during the Term a policy or policies of Workers'
Compensation Insurance and any other employee benefit insurance sufficient to
comply with all applicable laws, statutes, ordinances and governmental rules,
regulations or requirements.

     7.0 MAINTENANCE.

     7.1 Premises. Throughout the Term, Lessee agrees to keep and maintain all
improvements and appurtenances upon the Premises, including all sewer
connections, plumbing, heating and cooling appliances, wiring and glass, in good
order and repair including the replacement of such improvements and
appurtenances when necessary. Lessee hereby expressly waives the provisions of
any law permitting repairs by a tenant at the expense of a landlord, including,
without limitation, all rights of Lessee under Sections 1941 and 1942 of the
California Civil Code. Lessee agrees to keep the Premises clean and in sanitary
condition as required by the health, sanitary and police ordinances and
regulations of any political subdivision having jurisdiction. Lessee further
agrees to keep the interior of the Premises, such as the windows, floors, walls,
doors, showcases and fixtures clean and neat in appearance and to remove all
trash and debris which may be found in or around the Premises. If Lessor deems
any repairs and/or maintenance to be made by Lessee necessary and Lessee refuses
or neglects to commence such repairs and/or maintenance and complete the same
with reasonable dispatch upon demand, Lessor may enter the Premises and cause
such repairs and/or maintenance to be made and shall not be responsible to
Lessee for any loss or damage occasioned thereby except to the extent that
Lessee's personal property is damaged by the intentional misconduct or
negligence of Lessor or its contractors. Lessee agrees that upon demand, it
shall pay to Lessor the cost of any such repairs, together with accrued interest
from the date of payment at the highest rate allowable by law.

     7.2 Building. Lessor shall maintain the foundation, roof and exterior walls
(the "Structural Components") and the common areas, including but not limited to
hallways, elevators, and common bathrooms ("Building Common Areas"), of the
building in which the Premises are located in reasonably good order and repair,
except that damage occasioned by the act of Lessee shall be repaired by Lessor
at Lessee's expense. Lessee shall have the obligation to notify Lessor, in
writing, of any repairs or maintenance to the Structural Components or Building
Common Areas which may be required, and Lessor shall have a reasonable time to
make such repairs. The manner and method of maintenance and repair of the
Structural Components and Building Common Areas shall be at the reasonable
discretion of Lessor. Lessee, in addition to the rent and other charges provided
herein, agrees to pay to Lessor 67.2% (which for purposes of this Paragraph
shall be deemed to be Lessee's pro rata share) of the costs of maintaining
Building Common Areas (but not the Structural Components) as billed to Lessee by
Lessor. Such percentage was calculated by comparing the total square footage of
the Premises to the total square footage available for lease by Lessor of the
building in which the Premises are located.

                                      -10-
<PAGE>
     7.3 Common Areas. Lessor shall maintain the common areas of the Property
which shall include without limitation the landscaping, plazas and parking lots
in reasonably good order and condition, except that damage occasioned by the act
of Lessee shall be repaired by Lessor at Lessee's expense. Lessee shall have the
obligation to notify Lessor, in writing, of any repairs or maintenance to the
common areas which may be required, and Lessor shall have a reasonable time to
make such repairs. The manner and method of maintenance and repair of the common
areas shall be at the reasonable discretion of Lessor. Lessee, in addition to
the rent and other charges provided herein, agrees to pay to Lessor its pro rata
share of the costs of maintaining the common areas in accordance with Paragraph
4.5.

     7.4 Alterations, Changes And Additions By Lessee. No changes, alterations,
or additions shall be made by Lessee to the Premises without the prior written
consent of Lessor which Lessor will not unreasonably withhold. Notwithstanding
the above, non-structural changes aggregating no more than $10,000 in any 12
month period may be made by Lessee without Lessor's consent. As used herein,
alterations include utility installations such as ducting, power panels,
fluorescent fixtures, base heaters, conduit and wiring. As a condition to giving
such consent, Lessor may require that Lessee agree to remove any such
alterations, additions or improvements at the expiration of the Term and to
restore the Premises to their prior condition. As a further condition to giving
such consent, Lessor may require Lessee to provide Lessor, at Lessee's sole cost
and expense, with a lien and completion bond in an amount equal to one and
one-half times the estimated cost of such improvements, to insure Lessor against
any liability for mechanics' and materialmen's liens and to insure completion of
the work. All changes, alterations or additions to be made to the Premises shall
be under the supervision of a competent architect or competent licensed
structural engineer and made in accordance with plans and specifications which
have been furnished to and approved by Lessor prior to commencement of work.
Lessor shall not unreasonably withhold its approval of such proposed
alterations. If the written consent of Lessor to any proposed alterations by
Lessee shall have been obtained, Lessee agrees to advise Lessor in writing of
the date upon which such alterations will commence in order to permit Lessor to
post a notice of nonresponsibility. All such alterations, changes and additions
shall be constructed in a good and workmanlike manner in accordance with all
ordinances and laws relating thereto. Any such changes, alterations or additions
to or on the Premises shall remain for the benefit of and become the property of
Lessor, unless Lessor requires the removal by giving Lessee written notice
within 30 days before the date Lessee is to vacate the Premises, in which case
Lessee shall remove such changes, alterations and additions and restore the
Premises to the condition they were in prior to such changes, alterations or
additions.

     7.5 Plumbing. Lessee shall not use the plumbing facilities for any purpose
other than that for which they were constructed. The expense of any breakage,
stoppage or other damage relating to the plumbing and resulting from the

                                      -11-
<PAGE>
introduction by Lessee, its agents, employees or invitees of foreign substances
into the plumbing facilities shall be borne by Lessee.

     7.6 Liens. Lessee shall keep the Premises free from any liens arising out
of work performed, materials furnished or obligations incurred by Lessee and
shall indemnify, hold harmless and defend Lessor from any liens and encumbrances
arising out of any work performed or materials furnished by or at the direction
of Lessee. In the event that Lessee shall not, within 20 days following the
imposition of any such lien, cause such lien to be released of record by payment
or posting of a proper bond, Lessor shall have, in addition to all other
remedies provided herein and by law, the right, but not the obligation, to cause
the same to be released by such means as it shall deem proper, including payment
of the claim giving rise to such lien. All such sums paid by Lessor and all
expenses incurred by it in connection therewith including attorneys' fees and
costs shall be payable to Lessor by Lessee on demand with interest at the
highest rate allowable by law. Lessor shall have the right at all times to post
and keep posted on the Premises any notices permitted or required by law, or
which Lessor shall deem proper, for the protection of Lessor and the Premises,
and any other party having an interest therein, from mechanics' and
materialmen's liens, and Lessee shall give to Lessor at least 10 business days'
prior written notice of the expected date of commencement of any work relating
to alterations or additions to the Premises.

     8.0 MANAGEMENT.

     Lessee shall bear its share of the costs to Lessor of managing the
Property. Lessee understands that Wareham Property Group, or another affiliated
or unaffiliated third party will be responsible for the management of the
Property. For the period through April 30, 1998, Lessee shall pay to Lessor a
property management fee equal to five percent of the monthly rent. Thereafter,
the monthly property management fee payable by Lessee shall be equal to the
monthly property management fee owing by Lessee immediately prior to May 1,
1998, subject to adjustment as follows. Commencing May 1, 1998 and each
anniversary thereafter, the monthly property management fee shall be adjusted
upwards by increases in the CPI between the Adjustment Date and the same date
one year earlier. The monthly property management fee shall be payable with
monthly rent.

     9.0 UTILITIES AND SERVICES.

     9.1 Premises. Lessee shall pay prior to delinquency throughout the Term the
cost of water, gas, heating, cooling, sewer, telephone, electricity, garbage,
air conditioning and ventilating, janitorial services and all other materials
and utilities supplied to the Premises, provided that if payment is to be made
to Lessor, it shall be made by Lessee within 30 days of receipt of the statement
for such charges.

     9.2 Common Areas. Lessor shall provide first-class landscaping, utilities,
janitorial and security services for the common areas of the Property. Lessee
shall bear its pro

                                      -12-
<PAGE>
rata share of such common area costs to Lessor in providing such services in
accordance with Paragraph 4.5. Security services shall include hiring of guards
in the discretion of Lessor during hours determined by Lessor. Notwithstanding
the above, any extraordinary landscaping, utilities, janitorial and/or security
services incurred on the Property as a result of special events held by the
tenants of Buildings A and B shall not be included in such common area costs.

     10.0 USE OF PREMISES.

     10.1 Use. The Premises shall be used and occupied by Lessee for only the
purposes specified in Paragraph 1.6 and for no other purposes whatsoever without
obtaining the prior written consent of Lessor which shall not be unreasonably
withheld.

     10.2 Suitability. This Lease shall be subject to all applicable zoning
ordinances and to any municipal, county and state laws and regulations governing
and regulating the use of the Premises. Lessee acknowledges that neither Lessor
nor Lessor's agent has made any representation or warranty as to the suitability
of the Premises for the conduct of Lessee's business.

     10.3 Uses Prohibited.

     a. Rate Of Insurance. Lessee shall not do or permit anything to be done in
or about the Premises which will cause the existing rate of insurance upon the
Premises (unless Lessee shall pay an increased premium as a result of such use
or acts) or cause the cancellation of any insurance policy covering said
Premises, nor shall Lessee sell or permit to be kept, used or sold in or about
such Premises any articles which may be prohibited by a standard form policy of
fire insurance.

     b. Interfere With Other Tenants. Lessee shall not do or permit anything to
be done in or about the Premises which will in any way obstruct or unreasonably
interfere with the rights of other tenants or occupants of the Property or
injure or annoy them or use or allow the Premises to be used for any unlawful or
objectionable purpose, nor shall Lessee cause, maintain or permit any nuisance
in, or about the Premises. Lessee shall not commit or suffer to be committed any
waste in or upon the Premises.

     c. Applicable Laws. Lessee shall not use the Premises or permit anything to
be done in or about the Premises which will in any way conflict with any law,
statute, zoning restriction, ordinance, governmental rule, regulation or
requirements of duly constituted public authorities whether now in force or
which may hereafter be enacted or promulgated. Lessee shall at its sole cost and
expense properly comply with all laws, statutes, ordinances and governmental
rules, regulations or requirements now in force or which may hereafter be in
force and with the requirements of any board of fire underwriters or other
similar body now or hereafter constituted relating to or affecting the
condition, use or occupancy of the Premises. The judgment of any court of
competent jurisdiction or the admission of Lessee in any action against Lessee,

                                      -13-
<PAGE>
whether Lessor be a party thereto or not, that Lessee has violated any law,
statute, ordinance or government rule, regulation or requirement, shall be
conclusive of that fact as between Lessor and Lessee.

     d. Signs. Lessee shall not place any sign upon the Premises or conduct any
auction thereon without Lessor's prior written consent.

     10.4 Lessee's Warranty. Lessee warrants that its use of the Premises
presently complies and shall comply with applicable federal, state and local
laws and regulations pertaining to (i) the use, storage and disposal of
radiological materials and/or toxic chemicals, (ii) the disposal of hazardous
waste and (iii) the safety of persons on the Premises, including but not limited
to, the general industry safety orders as set forth in Title 8 of the California
Administrative Code. Lessee further warrants that it will not interfere with any
actions by Lessor made in furtherance of the above laws and regulations and it
shall comply with any reasonable procedures and/or regulations promulgated by
Lessor from time to time in connection with the matters covered by such laws and
regulations, provided that Lessor shall have no duty to establish any procedures
or regulations or to supervise in any way Lessee's activities on the Premises.
Lessee warrants that all governmental inspections of the Premises as required
under the laws referenced above have been made and will be made, and Lessee
shall deliver within 15 days of the date hereof to Lessor a copy of the reports
of each such inspection most recently conducted. Lessee shall provide a copy of
the reports for each such future inspection within 15 days of Lessee's receipt
of such report. Except in instances when a governmental report of such
inspection has been made within the last 12 month period, Lessee shall obtain at
its sole cost an inspection by a private engineering firm, resulting in a
written report specifying Lessee's compliance, or enumerating the reasons for
Lessee's lack of compliance, with such regulations. Lessee indemnifies and shall
hold Lessor harmless from a breach of the above warranty and from any claim
arising from Lessee's particular use of the Premises, including but not limited
to, (a) the disposal or use of hazardous waste, or (b) the disposal or escape of
odorous, carcinogenic and/or pathogenic exhaust from the Premises. Lessee shall
pay all of Lessor's costs and reasonable attorneys' fees arising from a breach
of Lessee's warranty set forth above, whether or not litigation is commenced,
including but not limited to, the costs of defending any claims made against
Lessor as a result of such breach. Lessor shall have the right to defend such
claims with attorneys of its own election and Lessee shall pay the cost thereof.
Nothing herein shall suggest that Lessee shall be responsible for the condition
of the Property prior to its first obtaining possession of the Premises.

     11.0 DEFAULT PROVISIONS.

     11.1 Insolvency. If, during the Term, Lessee shall be declared insolvent or
bankrupt, or if any assignment of Lessee's property shall be made for the
benefit of creditors or otherwise, or if Lessee's leasehold interest herein
shall be

                                      -14-
<PAGE>
levied upon under execution or seized by virtue of any writ of any court of law,
or a trustee in bankruptcy or a receiver be appointed for the property of
Lessee, any such occurrence shall be a material default of this Lease, and
entitle Lessor at its election to terminate the Lease.

     11.2 Non-Payment, Breach Or Vacating. If (a) Lessee shall fail to make
payment of any rent or any charge owing hereunder, or (b) any other covenant,
condition, agreement or obligation of Lessee hereunder is not timely performed
and either the breach is not cured within 15 days after written notice from
Lessor or the cure of the breach is not commenced within 15 days after written
notice from Lessor and thereafter diligently prosecuted towards completion,
Lessee shall be in default and Lessor shall be entitled to take the actions set
forth in Paragraphs 11.4 and 11.5 below and Lessor may pursue any other remedy
available by law.

     11.3 Default Under Other Leases. Any default under either the Building E
Lease or the Heinz Street Lease shall be deemed a default under this Lease,
entitling Lessor to take the actions set forth in Paragraphs 11.4 and 11.5 below
and Lessor may pursue any other remedy available by law.

     11.4 Lessor's Right to Relet. Upon recovery of possession of the Premises,
whether with or without legal proceedings, by reason of Lessee's breach of this
Lease, Lessor may, at its option, at any time and from time to time, remove any
signs and property of Lessee therefrom and relet the Premises or any part
thereof at such rent and upon such terms and conditions as Lessor in its
discretion shall determine, and the term of such reletting may be for a term
extending beyond the Term. Such reletting shall neither void nor terminate this
Lease. For the purpose of such reletting, Lessor is authorized to make repairs
or alterations in or to the Premises at the sole expense of Lessee as may be
necessary or desirable for the purpose of such reletting. The costs and expenses
of such reletting, including repairs and alterations and any reasonable real
estate commissions associated with such reletting shall be paid by Lessee. If a
sum shall not be realized from such reletting to equal the monthly rent payable
hereunder plus all other monthly charges to be paid by Lessee hereunder, less
any amount of rental loss for the same period which Lessee proves could be
reasonably avoided by Lessor, Lessee will pay such deficiency each month to
Lessor. In no event shall Lessor be entitled to any excess rent received by
Lessor. No re-entry, taking of possession or reletting of the Premises by Lessor
shall be construed as an election to terminate this Lease unless written notice
of such intention is given to Lessee or unless terminated thereof is decreed by
a court of competent jurisdiction.

     11.5 Right To Terminate. Notwithstanding any such reletting without
termination, Lessor may at any time during the Term elect to terminate the Lease
by reason of a previous breach. In the event that Lessor shall at any time
terminate this Lease by reason of breach thereof by Lessee, then Lessor, in
addition to any other remedy it may have, may recover from Lessee any damages
incurred by reason of such breach including, without limitation, the cost of
recovering the Premises, and

                                      -15-
<PAGE>
the amount by which the rent then unpaid for the balance of the Term exceeds the
amount of such rental loss for the same period which the Lessee proves could be
reasonably avoided by Lessor. Lessee hereby waives all statutory rights
inconsistent with this Paragraph.

     11.6 Default By Lessor. Lessor will be in default if Lessor fails to
perform any obligation required of Lessor (other than a delay in delivery of
possession as provided for in Paragraph 3.2 above) within 30 days after written
notice by Lessee, specifying wherein Lessor has failed to perform such
obligation; provided that if the nature of Lessor's obligation is such that more
than 30 days are required for performance, then Lessor shall not be in default
if Lessor commences performance within such 30 day period and thereafter
diligently prosecutes the same to completion; and provided further that if the
performance of any obligation required by Lessor is necessary to correct a
condition that poses a threat to life or property, then Lessor shall perform
such obligation as soon as reasonably possible after receiving written notice
from Lessee, specifying that the condition is threatening.

     12.0 EXPIRATION OR TERMINATION.

     12.1 Surrender Of Possession. Lessee agrees to deliver up and surrender to
Lessor possession of the Premises and all improvements thereon, subject to the
terms of Paragraph 7.4 above, in as good order and condition as when possession
was taken by Lessee, excepting only ordinary wear and tear. Upon termination of
this Lease, Lessor may reenter the Premises and remove all persons and property
therefrom. If Lessee shall fail to remove any effects which it is entitled to
remove from the Premises upon the termination of this Lease, for any cause
whatsoever, Lessor, at its option, may remove the same and store or dispose of
them, and Lessee agrees to pay to Lessor on demand any and all expenses incurred
in such removal and in making the Premises free from all dirt, litter, debris
and obstruction, including all storage and insurance charges. If the Premises
are not surrendered at the end of the Term, Lessee shall indemnify Lessor
against loss or liability resulting from delay by Lessee in so surrendering the
Premises, including, without limitation, any claims made by any succeeding
Lessee founded on such delay.

     12.2 Holding Over. If Lessee, with Lessor's consent, remains in possession
of the Premises after expiration of the term and if Lessor and Lessee have not
executed an express written agreement as to such holding over, then such
occupancy shall be a tenancy from month to month at a monthly rental equivalent
to 110% of the monthly rental in effect immediately prior to such expiration,
such payments to be made as herein provided. In the event of such holding over
all of the terms of this Lease including the payment of all charges owing
hereunder other than rent shall remain in force and effect on said month to
month basis.

     12.3 Voluntary Surrender. The voluntary or other surrender of this Lease by
Lessee, or a mutual cancellation thereof, shall not work a merger, but shall, at
the option of Lessor, terminate all or any existing subleases or

                                      -16-
<PAGE>
subtenancies, or operate as an assignment to Lessor of any or all such subleases
or subtenancies.

     13.0 CONDEMNATION OF PREMISES.

     13.1 Total Condemnation. If the entire Premises, whether by exercise of
governmental power or the sale or transfer by Lessor to any condemnor under
threat of condemnation or while proceedings for condemnation are pending, at any
time during the Term, shall be taken by condemnation such that there does not
remain a portion suitable for occupation, this Lease shall then terminate as of
the date transfer of possession is required. Upon such condemnation, all rent
shall be paid up to the date transfer of possession is required, and Lessee
shall have no claim against Lessor for the value of the unexpired term of this
Lease.

     13.2 Partial Condemnation. If any portion of the Premises is taken by
condemnation during the Term, whether by exercise of governmental power or the
sale or transfer by Lessor to any condemnor under threat of condemnation or
while proceedings for condemnation are pending, this Lease shall remain in full
force and effect; except that in the event a partial taking leaves the Premises
unfit for normal and proper conduct of the business of Lessee, then Lessee shall
have the right to terminate this Lease effective upon the date transfer of
possession is required. Moreover, Lessor shall have the right to terminate this
Lease effective on the date transfer of possession is required if more than 33%
of the total square footage of the Premises or the Property is taken by
condemnation. Lessee and Lessor may elect to exercise their respective rights to
terminate this Lease pursuant to this Paragraph by serving written notice to the
other within 30 days of their receipt of notice of condemnation. All rent shall
be paid up to the date of termination, and Lessee shall have no claim against
Lessor for the value of any unexpired term of this Lease. If this Lease shall
not be cancelled, the rent after such partial taking shall be that percentage of
the adjusted base rent specified herein, equal to the percentage which the
square footage of the untaken part of the Premises, immediately after the
taking, bears to the square footage of the entire Premises immediately before
the taking. Any sums owing hereunder which are calculated on the basis of
Lessee's pro rata share (as set forth in Paragraph 1.4) shall also be adjusted
to reflect the decreased square footage of the Premises due to the condemnation.
If Lessee's continued use of the Premises requires alterations and repairs by
reason of a partial taking, all such alterations and repairs shall be made by
Lessee at Lessee's expense.

     13.3 Award To Lessee. In the event of any condemnation, whether total or
partial, Lessee shall have the right to claim and recover from the condemning
authority such compensation as may be separately awarded or recoverable by
Lessee for loss of business, fixtures or equipment belonging to Lessee
immediately prior to the condemnation. The balance of any condemnation award
shall belong to Lessor and Lessee shall have no further right to recover from
Lessor or the condemning authority for any additional claims arising out of such
taking.

                                      -17-
<PAGE>
     14.0 ENTRY BY LESSOR.

     Lessee shall permit Lessor and its agents to enter the Premises at all
reasonable times for any of the following purposes: to inspect the Premises; to
maintain the Structural Components of the Premises; to make such repairs to the
Premises as Lessor is obligated or may elect to make; to make repairs,
alterations or additions to any other portion of the Property; to show the
Premises and post "To Lease" signs for the purposes of reletting during the last
90 days of the Term; to show the Premises as part of a prospective sale by
Lessor or to post notices of nonresponsibility. Notwithstanding the above,
except in the case of emergencies, Lessor shall give at least 24 hours prior
written notice before entry to either the laboratories or other non-office
restricted areas. Lessor shall have such right of entry without any rebate of
rent to Lessee for any loss of occupancy or quiet enjoyment of the Premises
thereby occasioned.

     15.0 INDEMNIFICATION.

     Lessee agrees not to hold Lessor liable for any injury or damage, either
proximate or remote, occurring through or caused by any repairs or alterations
to the Premises, except to the extent such injury or damage arises from the
willful misconduct or negligence of Lessor. Lessee agrees that Lessor shall not
be liable for any injury or damage occasioned by defective electric wiring, or
the breaking, bursting, stoppage or leaking of any part of the plumbing, air
conditioning, heating, fire-control sprinkler systems or gas, sewer or steam
pipes, except to the extent such injury or damage arises from the willful
misconduct or negligence of Lessor. Lessee will save and hold harmless Lessor
from all loss, expense, damage or injury to persons or property arising from or
occurring by reason of its occupation or use of the Premises, except to the
extent such losses or injuries are proximately caused by any willful misconduct
or negligence of Lessor. Lessor shall not be liable for any damage to or loss of
property of Lessee or other persons located on the Premises, and Lessee shall
hold Lessor harmless from any claims arising out of damage to the same, except
to the extent such loss or damage is proximately caused by the willful
misconduct or negligence of Lessor.

     16.0 ASSIGNMENT AND SUBLETTING.

     Lessee shall not assign this Lease in whole or in part, or sublet the
Premises or any part thereof, or license the use of all or any portion of the
Premises or business conducted thereon, or encumber or hypothecate this Lease,
without first obtaining the written consent of Lessor, which consent will not be
unreasonably withheld. Lessee shall submit in writing to Lessor: (a) the name
and legal composition of the proposed sublessee; (b) the nature of the proposed
sublessee's business to be carried on in the Premises; (c) the terms and
provisions of the proposed sublease; and (d) such financial and other reasonable
information as Lessor may request concerning the proposed sublessee. Any
assignment, subletting, licensing, encumbering, or hypothecating of this Lease
without such prior written consent shall, at the option of Lessor, constitute
grounds for termination of this Lease.

                                      -18-
<PAGE>
Lessor's consent to any assignment or sublease shall not constitute a waiver of
the necessity for such consent to any subsequent assignment or sublease. This
prohibition against assignment and subletting shall be construed to include a
prohibition against assignment or subletting by operation of law.
Notwithstanding any assignment or subletting with Lessor's consent, Lessee shall
remain fully liable on this Lease and shall not be released from its obligations
hereunder. In the event Lessor shall consent to a sublease or assignment under
this Paragraph, Lessee shall pay Lessor's reasonable attorneys' fees incurred in
connection with giving such consent. In addition, Lessee shall pay to Lessor
with its regularly scheduled rent payments 75% of all sums collected by Lessee
from a sublessee or assignee which are in excess of the rent and charges then
owing to Lessor pursuant to this Lease.

     17.0 DAMAGE OR DESTRUCTION.

     17.1 Right To Terminate On Destruction Of Premises. Lessor shall have the
right to terminate this Lease if, during the Term, the Premises are damaged to
an extent exceeding 33% of the then reconstruction cost of the Premises as a
whole. Lessor shall also have the right to terminate this Lease if any portion
of the Premises is damaged by an uninsured peril. In either case, Lessor may
elect to so terminate by written notice to Lessee delivered within 30 days of
the happening of such damage.

     17.2 Repairs By Lessor. If Lessor shall not elect to terminate this Lease
pursuant to Paragraph 17.1, Lessor shall, immediately upon receipt of insurance
proceeds paid in connection with such casualty, but in no event later than 90
days after such damage has occurred, proceed to repair or rebuild the Premises,
on the same plan and design as existed immediately before such damage or
destruction occurred, subject to such delays as may be reasonably attributable
to governmental restrictions or failure to obtain materials or labor, or other
causes beyond the control of Lessor. Lessee shall be liable for the repair and
replacement of all fixtures, leasehold improvements, furnishings, merchandise,
equipment and personal property not covered by the property insurance described
in Paragraph 6.2.

     17.3 Reduction Of Rent During Repairs. In the event Lessee is able to
continue to conduct its business during the making of repairs, the rent then
prevailing will be equitably reduced in the proportion that the unusable part of
the Premises bears to the whole thereof for the period that repairs are being
made. No rent shall be payable while the Premises are wholly unusable due to
casualty damage.

     17.4 Arbitration. Any controversy or claim arising out of or relating to
this Paragraph shall be settled by arbitration in accordance with the rules of
the American Arbitration Association as then in effect, and judgment upon the
award rendered by the arbitration may be entered in any court having
jurisdiction. The expenses of arbitration shall be borne by the parties as
allocated by the arbitrators. The party desiring arbitration shall serve notice
upon the other party, together with designation of the first party's arbitrator.

                                      -19-
<PAGE>
     17.5 Lessor's Overriding Right To Terminate. Notwithstanding anything to
the contrary herein, if the discounted present value of the rent due hereunder
for the balance of the Term, using as the discount rate the prime commercial
lending rate in effect at the Bank of America as of the date Lessor is to
commence repairs pursuant to Paragraph 17.2 hereof, is less than the cost of
repairing the damage to the Premises, Lessor may at its option terminate this
Lease upon 10 days' written notice.

     18.0 MISCELLANEOUS PROVISIONS.

     18.1 Waiver. No waiver of any breach of any of the covenants or conditions
of this Lease shall be construed to be a waiver of any other breach or to be a
consent to any further or succeeding breach of the same or other covenant or
condition. The subsequent acceptance of rent hereunder by Lessor shall not be
deemed to be a waiver of any preceding breach by Lessee of any term, covenant or
condition of this Lease, other than the failure of Lessee to pay the particular
rent so accepted, regardless of Lessor's knowledge of such preceding breach at
the time of acceptance of such rent.

     18.2 Successors And Assigns. Except as otherwise provided herein, the
provisions hereof shall be binding upon and shall inure to the benefit of the
heirs, personal representatives, successors and assigns of the parties.

     18.3 Notices. All notices, requests, demands and other communications
required or permitted to be given hereunder shall be in writing and either
personally delivered or sent by certified mail, return receipt requested,
postage prepaid, properly addressed to the other party at the address set forth
next to its signature below, or at such other address or addresses as may from
time to time be designated in like manner by one party to the other. Any such
notice shall be deemed given when personally delivered or on the date indicated
on the Post Office's certified mail receipt.

     18.4 Partial Invalidity. If for any reason any provision of this Lease
shall be determined to be invalid or inoperative, the validity and effect of the
other provisions hereof shall not be affected thereby.

     18.5 Number And Gender. All terms in this Lease shall be construed to mean
either the singular or the plural, masculine, feminine or neuter, as the
situation may demand.

     18.6 Descriptive Headings. The headings used herein and in any of the
documents attached hereto as schedules, lists or exhibits are descriptive only
and for the convenience of identifying provisions, and are not determinative of
the meaning or effect of any such provisions.

     18.7 Time Is Of The Essence. In all matters time is of the essence in the
performance of all obligations under this Lease.

                                      -20-
<PAGE>
     18.8 Entire Agreement. This Lease and the documents attached hereto as
schedules, lists or exhibits, constitute the entire agreement and understanding
between the parties with respect to the subject matters herein and therein, and
supersede and replace any prior agreements and understandings, whether oral or
written, between and among them with respect to the lease of the Premises,
rental therefor, use thereof and all other such matters. The provisions of this
Lease may be waived, altered, amended or repealed in whole or in part only upon
the written consent of Lessor and Lessee.

     18.9 Memorandum Of Lease. Lessor and Lessee mutually agree that they will
not file or record a copy of this Lease, but that in the event Lessor or Lessee
requests a recording, Lessor and Lessee shall execute and acknowledge a
memorandum of this Lease in a form approved by the parties setting forth in said
memorandum the description of the Premises, the date of the Lease, the
Commencement Date and the date of termination. Said memorandum of Lease may be
recorded in the Recorder's Office of the County in which the Premises are
located.

     18.10 Applicable Law. This Lease Agreement construed and interpreted in
accordance with the laws of the State of California.

     18.11 Corporate Authority. Each individual executing this Lease on behalf
of a corporation represents and warrants that he is duly authorized to execute
and deliver this Lease on behalf of the corporation in accordance with a duly
adopted resolution of the Board of Directors of the corporation, and that this
Lease is binding upon said corporation in accordance with its terms.

     18.12 Litigation Expense. If any party shall bring an action against any
other party hereto by reason of the breach of any covenant, warranty,
representation or condition hereof, or otherwise arising out of this Agreement
or any schedule, list or exhibit hereto, whether for declaratory or other
relief, the prevailing party in such suit shall be entitled to such party's
costs of suit and attorneys' fees, which shall be payable whether or not such
action is prosecuted to judgment.

     18.13 Subordination Of Leasehold. Lessee agrees that this Lease is and
shall be, at all times, subject and subordinate to the lien of any mortgage or
other encumbrances which Lessor may create against the Premises including all
renewals, replacements and extensions thereof; provided, however, that
regardless of any default under any such mortgage or encumbrance or any sale of
the Premises under such mortgage, so long as Lessee performs all covenants and
conditions of this Lease and continues to make all payments hereunder, this
Lease and Lessee's possession and rights hereunder shall not be disturbed by the
mortgagees or anyone claiming under or through such mortgages. Lessee agrees to
execute any and all instruments in writing which may be required by Lessor to
subordinate Lessee's rights to the lien of such mortgage.

     18.14 Lessee's Certificate. Within 15 days following Lessor's request,
Lessee shall complete, execute and

                                      -21-
<PAGE>
deliver to Lessor a Lessee's Certificate, setting forth the information
requested therein including, but not limited to (a) certification that this
Lease is unmodified and in full force and effect (or if modified, stating the
nature of such modification and certifying that this Lease as so modified is in
full force and effect) and the date to which the rental and other charges are
paid in advance, if any, (b) acknowledgement that there are not, to Lessee's
knowledge, any uncured defaults on the part of Lessor hereunder, or specifying
such defaults if any are claimed and (c) setting forth the date of commencement
and expiration of the Term. Failure of Lessee to deliver such Certificate within
said 15 days shall be deemed to be an acknowledgement that Lessor is not in
default under the Lease, and that the terms of the Lease have not been modified
or supplemented in any way. It is intended that such Certificate may be relied
upon by any prospective purchaser, lender or assignee of any lender of the
Premises.

     18.15 Attornment. Lessee shall, in the event of any sale of the Premises or
if proceedings are brought for the foreclosure of, or in the event of exercise
of the power of sale under, any mortgage, installment land contract or deed of
trust made by Lessor covering the Premises, attorn to the mortgagee or the
purchaser upon any such foreclosure or sale and recognize such mortgagee or
purchaser as Lessor under this Lease, provided that Lessee's possession and
rights hereunder shall not be disturbed by the mortgagee or purchaser.

     18.16 Day. As used herein, the term "day" shall mean, unless otherwise
specifically stated, a calendar day.

     18.17 Brokers. The only broker's fees in connection with this Lease shall
be payable by Lessor to Coldwell Banker. Each party hereby indemnifies and
agrees to hold the other harmless from any and all other broker fees.

     IN WITNESS WHEREOF, the parties have executed this Lease on the day and
year first written above.

LESSOR:                                   LESSEE:

SEVENTH STREET PROPERTIES II              XOMA CORPORATION
1120 Nye Street, Suite 400
San Rafael, CA 94915
                                                  (Address)

By /s/ Richard K. Robbins                 By /s/ Steven C. Mendell
(Signature)                                    (Signature)

Richard K. Robbins                        Steven C. Mendell/ CEO
(Print Name & Title)                       (Print Name & Title)

                                      -22-
<PAGE>
                                    EXHIBIT A

                      DESCRIPTION OF PREMISES AND PROPERTY

                       (Drawing of Building inserted here)





                                      -23-
<PAGE>
                                    EXHIBIT B

                WORK TO BE PERFORMED BEFORE OCCUPANCY OF PREMISES

     Lessor shall deliver the Premises to Lessee in shell condition. As used
herein, "shell condition" shall mean that the Premises shall include all of the
following: exterior walls with windows and doors, roof structure and roofing,
concrete slab, exterior painting, fire sprinklers, roof drainage, standard
building utilities brought to the Premises but not distributed, male and female
toilets, landscaping, parking lot, storm sewers, sidewalks, electrical secondary
cable and conduit, site lighting, roof hatch and ladder, and rock below slab.

     Lessee shall construct all tenant improvements to be placed on the Premises
in accordance with the working drawings approved in writing by Lessor. Lessee
shall be entitled to an allowance of $15.00 per square foot of leaseable space
(the "Allowance") for the construction of the tenant improvements and the
preparation of the working drawings therefor. If the cost of the tenant
improvements exceeds the Allowance, such excess shall be borne by Lessee, at its
own expense. The Allowance shall be paid to Lessee in cash within 15 days of
occupancy of the Premises by Lessee and approval of the tenant improvements by
Lessor.

                                     - 24 -







                                  July 22, 1987

Mr. Ho Humphrey
Xoma Corporation
2910 Seventh Street
Emeryville, CA  94710

             RE:  BUILDINGS C, E AND F
                  LEASES AT AQUATIC PARK CENTER.

Dear Ho:

     This will confirm our agreement modifying those certain Leases entered into
by Xoma Corporation with Seventh Street Properties II dated July 22, 1987 for
certain space within Buildings C, E and F at the Aquatic Park Center.
Notwithstanding anything to the contrary in the Leases, if the Commencement Date
under one or more of the Leases is later than May 1, 1988, then the first
Adjustment Date under Paragraph 4.2 of those Leases for which there is such a
delayed Commencement Date shall be changed to that date which is "X" number of
days after October 1, 1990. As used above, "X" shall be the number of days
falling between May 1, 1988 and the Commencement Date for the Lease. Each Lease
shall be considered separately such that if, by way of example only, the
Commencement Date for Buildings C and E are before May 1, 1988 and the
Commencement Date for Building F is after May 1, 1988, then only the Adjustment
Date for Building F shall be changed as set forth above. If an Adjustment Date
is changed, then subsequent Adjustment Dates for such Lease shall be each three
years thereafter on the same date as such new Adjustment Date.

     Except as set forth above, the Leases remained unchanged and in full force
and effect. Please indicate your


<PAGE>


Mr. Ho Humphrey
July 22, 1987
Page 2

acceptance of the terms of this letter by signing a copy of this letter and
returning it directly to the undersigned.

                          SEVENTH STREET PROPERTIES II

                          By   /s/ Richard K. Robbins
                               ------------------------------
                                   RICHARD K. ROBBINS,
                                   General Partner

The terms set forth above are hereby agreed to on July 22, 1987.

XOMA CORPORATION

By /s/ Steven C. Mendell
- ----------------------------
         (Signature)

Chairman/ CEO
(Print Name & Title)








                                      XOMA
                                   CORPORATION
                                      LEASE


                                TABLE OF CONTENTS

                                                                            PAGE

1.       DEFINITIONS                                                           1
         1.1          Term
         1.2          Commencement Date
         1.3          Base Monthly Rent
         1.4          Premises
         1.5          Building
         1.6          Property
         1.7          Agents
         1.8          Day and Month
         1.9          Lease Year
         1.10         Common Area
         1.11         Tax
         1.12         Alteration
         1.13         Operating Expenses
         1.14         Base Year
         1.15         Tenant Pro Rata Share
         1.16         Floor Area - Premises                                    2
         1.17         Floor Area - Building
         1.18         Consent/Approval
         1.19         Regulation
         1.20         Condemnation

2.       PREMISES                                                              2
         2.1          Description
         2.2          Tenant Improvements
         2.3          Possession

3.       TERM                                                                  2
         3.1          Term
         3.2          Delay in Commencement

4.       RENT                                                                  3
         4.1          Base Monthly Rent
         4.2          Base Monthly Rent Adjustment
         4.3          Mode of Payment
         4.4          Additional Rent
         4.5          Base Year Operating Expenses                             4
         4.6          Security Deposit
         4.7          Late Charges                                             5

5.       TAXES                                                                 5
         5.1          Real and Personal Property Taxes
         5.2          Taxes on Tenant's Property

6.       INSURANCE    5
         6.1          Property Insurance
         6.2          Fixtures
         6.3          Landlord's Liability Insurance
         6.4          Tenant's Liability Insurance
         6.5          Subrogation Waiver                                       6
<PAGE>
         6.6          Indemnification
         6.7          Plate Glass Replacement
         6.8          Worker's Compensation

7.       MAINTENANCE                                                           6
         7.1          Premises
         7.2          Common Areas and Systems
         7.3          Alterations, Changes and Additions by Tenant             7
         7.4          Use of Plumbing, Electrical and HVAC Systems
         7.5          Liens

8.       MANAGEMENT                                                            7

9.       UTILITIES AND SERVICES                                                8
         9.1          Premises
         9.2          Common Areas
         9.3          Limitation of Liability

10.      USE OF PREMISES                                                       8
         10.1         Use
         10.2         Suitability
         10.3         Uses Prohibited                                          9
                      10.3.1  Rate of Insurance
                      10.3.2  Interference with Other Tenants
                      10.3.3  Applicable Laws
                      10.3.4  Auctions

11.      DEFAULTS AND REMEDIES                                                 9
         11.1         Tenant Default
         11.2         Landlord's Remedies
         11.3         Landlord's Default                                      10

12.      EXPIRATION OR TERMINATION                                            10
         12.1         Surrender of Possession
         12.2         Holding Over
         12.3         Voluntary Surrender

13.      CONDEMNATION OF PREMISES                                             11
         13.1         Total Condemnation
         13.2         Partial Condemnation
         13.3         Award to Tenant
         13.4         Waiver of Partial Termination Rights

14.      ENTRY BY LANDLORD                                                    11

15.      LIABILITY LIMITATION AND INDEMNIFICATION                             11
         15.1         Limitation of Landlord's Liability
         15.2         Limitation of Enforcement of Judgments                  12

16.      ASSIGNMENT AND SUBLETTING                                            12
         16.1         Generally
         16.2         Tenant's Payments                                       13
<PAGE>
17.      DAMAGE OR DESTRUCTION                                                13
         17.1         Right to Terminate on Destruction of Property
         17.2         Repairs by Landlord
         17.3         Reduction of Rent During Repairs
         17.4         Waiver
         17.5         Landlord's Overriding Right to Terminate

18.      HAZARDOUS MATERIALS                                                  14
         18.1         Tenant's Obligations
                      18.1.1  Restrictions on Hazardous Materials
                      18.1.2  Applicable Regulations
                      18.1.3  Restoration
                      18.1.4  Removal
                      18.1.5  Tenant's Written Confirmation
                      18.1.6  Tenant's Duty to Notify Landlord
         18.2         Landlord's Rights                                       15
         18.3         Tenant's Duty to Indemnify
         18.4         Right of Entry
         18.5         Definitions
                      18.5.1  "Hazardous Material"
                      18.5.2  "Environmental Health and Safety Requirement"   16
         18.6         Allocation of Responsibilities
         18.7         Inspections
         18.8         Survival
         18.9         Storage Tanks
         18.10        Landlord's Obligations                                  17
                      18.10.1  Restrictions on Hazardous Materials
                      18.10.2  Compliance With Regulations
                      18.10.3  Restoration
                      18.10.4  Duty to Notify Tenant
                      18.10.5  Landlord's Indemnity of Tenant

19.      MISCELLANEOUS PROVISIONS                                             17
         19.1         Waiver
         19.2         Successors and Assigns
         19.3         Notices
         19.4         Partial Invalidity
         19.5         Number and Gender
         19.6         Descriptive Headings                                    18
         19.7         Time
         19.8         Entire Agreement
         19.9         Memorandum of Lease
         19.10        Applicable Law
         19.11        Authority
         19.12        Litigation Expense
         19.13        Subordination of Leasehold
         19.14        Estoppel Certificate
         19.15        Attornment
         19.16        Compliance With Lender's Requests                       19
         19.17        Rules and Regulations
         19.18        Delete
         19.19        Submission of Lease
         19.20        Arbitration of Disputes
         19.21        Venue

<PAGE>
         19.22        Representation by Counsel                               19
         19.23        Brokerage                                               20
         19.24        Parking
         19.25        Use of Amenities
         19.26        Signs
         19.27        Cooperation
         19.28        First Right of Refusal

20.      TERMINATION OF OLD LEASE                                             21

Exhibit A & B
<PAGE>
                                                                          032392
                                  OFFICE LEASE

     This Lease is made and entered into as of March 25, 1992, between 7th
Street Property General Partnership ("Landlord") and Xoma Corporation, a
corporation authorized to do business in California ("Tenant").

1.   DEFINITIONS.

Words not defined in this section or elsewhere in this Lease have their
customary meanings.

     1.1. "Term" is 11 years and six months beginning with the Commencement Date
and continuing through September 30, 2003.

     1.2. "Commencement Date" is the first day of the Term which is April 1,
1992.

     1.3. "Base Monthly Rent" means $1.85 per square foot of the Premises,
subject to adjustment as provided in this Lease.

     1.4. "Premises" means, subject to adjustment, the part of the Building
leased to Tenant for exclusive use, consisting of approximately 29,584 square
feet as shown in Exhibit A.

     1.5. "Building" means the structure in which the Premises are located. The
Property's address is: 2910 Seventh Street, Berkeley, California;

     1.6. "Property" includes the Building and land on which it stands;

     1.7. "Agents" includes employees, agents, guests, invitees and, when
applied to Tenant, subtenants and assignees;

     1.8. "Day" and "Month" mean calendar day/month;

     1.9. "Lease Year" means consecutive 12 month periods starting on the
Commencement Date;

     1.10. "Common Area" means parts of the Building not for exclusive use by
Tenants including halls, lobby, elevators, rest rooms, roof, exterior walls and
structural components;

     1.11. "Tax" means any form of assessment, license, fee, rent, tax, levy,
penalty or tax imposed by any authority having direct or indirect taxing powers
(including Improvement Districts) against Landlord's interest in the Property or
personal property used in the operation of the Property and/or Landlord's
business of renting the Property; notwithstanding the foregoing, the following
shall be excluded from Tax any time that term is used to refer to payments to be
made by Tenant: all property tax increases based upon the construction of new
improvements on the Property which improvements have not been agreed to by
Tenant (nothing in the preceding sentence shall be construed to require that
Landlord obtain Tenant's approval prior to construction of any improvements upon
the Property) and one half (50%) of the amount of any property tax increase
based upon a reassessment of the Property upon a change of ownership of the
Property;

     1.12. "Alteration" includes additions, deletions, modifications and changes
including utility installations such as ducting, power panels, fixtures,
heaters, conduit and wiring;

     1.13. "Operating Expenses" are all expenses for maintenance, servicing,
management and repair of the Property and the Premises inclusive of Taxes and
insurance premiums. In the event that any Operating Expenses are incurred for
less than one full calendar year during the Base Year, the expense(s) shall be
annualized for calculations respecting Base Year Operating Expenses. Operating
Expenses shall not be interpreted to include capital expenses for structural
modification of the Building;

     1.14. "Base Year" for matters other than Taxes is the calendar year in
which Tenant executes this Lease and for Tax matters is the Tax year in which
Tenant executes this Lease;

     1.15. Tenant's "Pro Rata Share" of any item or expense means the total cost
of any such item or expense multiplied by a fraction, the numerator of which is
the total floor area of the Premises and the denominator of which is the total
floor area of the Building exclusive of the Common Area. An appropriate
adjustment to Tenant's Pro Rata Share shall be made if the actual square footage
of the Premises is other than as set forth in paragraph 2.1 or the square
footage of the Premises or the Property changes. Unless adjusted, Tenant's Pro
Rata Share shall be 73.3%.

                                        1
<PAGE>
[Landlord may, however, adjust Tenant's Pro Rata Share of specific Operating
Expenses if Landlord reasonably determines that Tenant's usage warrants such
adjustment, subject to Tenant's reasonable review of such adjustment];

     1.16. The "floor area of the Premises" is measured from the exterior
surface of exterior walls and the center of walls separating the Premises from
adjacent premises or common areas;

     1.17. The "floor area of the Building" is measured from the exterior
surface of exterior walls including common and core areas;

     1.18. "consent" and "approval" require reasonable conduct by the acting
party;

     1.19. "Regulation" includes all laws, statutes, regulations and
requirements adopted by duly constituted public authorities now in force or
hereafter adopted;

     1.20. "Condemnation" includes taking by exercise of governmental power or
sale or transfer to any condemnor under threat of or during the pendency of
condemnation proceedings.

2.       PREMISES.

     2.1. Description. Landlord hereby leases the Premises to Tenant for its
exclusive use and occupancy subject to the provisions of this Lease. In addition
to the square footage described above, Tenant shall be deemed to occupy an
additional 11.1% of such square footage (an additional 3,284 square feet for a
total of 32,868 square feet) for purposes of the calculation of Base Monthly
Rent and for the purpose of all Pro Rata Share calculations. Said 11.1%
represents Tenant's share of the rental charges for the Common Area. For all
calculations required under this Lease respecting proration of expenses, costs
or charges, the Premises shall be deemed to consist of the square footage of the
Premises augmented by the square footage of the Common Area attributable to
Tenant pursuant to this paragraph (sometimes hereafter "Tenant's Common Area").
Tenant shall have a right to the non-exclusive use of the Common Area in
conjunction with all other tenants of the Property.

     2.2. Tenant Improvements. The obligations of Landlord and Tenant to perform
the work and supply material and labor to prepare the Premises for occupancy are
set forth in Exhibit B to this Lease. Landlord and Tenant shall expend all funds
and do all acts required of them in Exhibit B and shall have the work performed
promptly and diligently in a workmanlike manner. Tenant shall not commence the
construction of any improvements to be undertaken by Tenant until Landlord has
approved in writing the final drawings for said improvements.

     2.3. Possession. Tenant is already in possession of the Premises. Tenant
occupies a portion of the Premises under the terms of an existing Lease
agreement effective October 1, 1987 (hereafter the "Old Lease") between Tenant
as "Lessee" and Landlord (incorrectly named as Seventh Street Properties) as
"Lessor". Tenant occupies the remainder of the Premises under the provisions of
a month to month sublet from Sybase which right of occupancy terminated upon the
expiration of the Sybase lease on December 31, 1991. Tenant shall remain in
possession of the Premises under the terms of this Lease.

3.   TERM.

     3.1. Term. The Lease shall commence on the Commencement Date and shall
continue thereafter for the duration of the Term, unless sooner terminated
pursuant to this Lease.

     3.2. Delay in Commencement. If Landlord cannot deliver possession to Tenant
of that portion of the Premises not currently occupied by Tenant on the
Commencement Date, such failure shall not affect the validity of this Lease,
extend the Term nor render Landlord liable to Tenant for any loss resulting
therefrom. If possession of such portion of the Premises is not delivered to
Tenant on the Commencement Date for any reason other than a delay attributable
to Tenant and its Agents, Tenant shall not be obligated to pay rent on that
portion of the Premises not delivered to Tenant until Landlord tenders
possession of the Premises to Tenant. After 120 Days following the Commencement
Date have elapsed, if Landlord still cannot deliver possession of any portion of
the Premises to Tenant for any reason other than a delay attributable to Tenant
and its Agents, Tenant shall have the right to terminate this Lease on written
notice delivered to Landlord. In such event, Tenant shall have no further
recourse against Landlord respecting the Lease or Landlord's inability to
deliver the Premises to Tenant. Notwithstanding any other provision of this

                                        2
<PAGE>
Lease, Landlord shall have no obligation to pay damages or adjustments to Tenant
for delays outside of Landlord's control, including, without limitation, conduct
of Tenant and its Agents, acts of God, war, inclement weather and/or labor
strikes (including strikes affecting the supply of labor and/or materials).
Tenant's acceptance of possession of the Premises shall constitute an
irrevocable waiver of Tenant's right to terminate under the provisions of this
paragraph.

4.   RENT.

     4.1. Base Monthly Rent. On the Commencement Date and on the first Day of
each Month of the Term, Tenant shall pay to Landlord, in advance, in United
States dollars, as Base Monthly Rent for the Premises, the per square foot
rental rate set forth in paragraph 1.3 (as adjusted pursuant to paragraph 4.2)
multiplied by the square footage of the Premises as adjusted pursuant to
paragraph 2.1. The initial Base Monthly Rent (inclusive of Common Area allocated
to Tenant pursuant to paragraph 2.1 of this Lease) shall be $60,805.80. If the
actual square footage of the Premises is determined to be other than the
unadjusted amount set forth in paragraph 2.1, the Base Monthly Rent shall be
adjusted in proportion to the difference between the actual floor area and the
unadjusted amount set forth in paragraph 2.1. If alterations to the Premises
increase the square footage of the Premises, the Base Monthly Rent shall be
proportionately adjusted. If the Commencement Date is not the first Day of a
Month, such installment shall be applied per diem against payment of the rent
from the date rent commences until the first Day of the next succeeding Month.
Any unused portion of said amount shall be applied against payment of the rent
for the following Month, and the balance of the rent for that Month shall be due
on the first Day thereof.

     4.2. Base Monthly Rent Adjustment. The Base Monthly Rent payable under this
Lease shall be adjusted pursuant to the provisions of this paragraph during the
Term. All adjustments to the Base Monthly Rent shall be determined by reference
to the Consumer Price Index for All Urban Consumers, San Francisco-Oakland-San
Jose, California, All Items, published by the U.S. Bureau of Labor Statistics
(the "C.P.I."). Such increases shall be made as of each of the third, sixth and
ninth anniversaries of the Commencement Date (each such anniversary is sometimes
hereafter referred to as an "Adjustment Date"). In the event that the Term is
extended, in the absence of any contrary agreement of the parties, the rent will
continue to adjust every anniversary of the Commencement Date divisible evenly
by three (3, 6, 9, 12, etc.) Effective upon each Adjustment Date, the Base
Monthly Rent shall be increased by the percentage, if any, by which the C.P.I.
for the third Month prior to that Adjustment Date exceeds the C.P.I. for the
third Month prior to the Commencement Date (in the event of the first Adjustment
Date) or for the third Month prior to the immediately preceding Adjustment Date
(for the second and each subsequent Adjustment Date). If the C.P.I. is not
published for any Month herein specified, increases in Base Monthly Rent shall
be determined by reference to the C.P.I. available for the Month closest, but
prior to, such Month. If the C.P.I ceases to be published prior to expiration of
this Lease, the increases in Base Monthly Rent shall be determined by using such
comparable measure of the purchasing power of the consumer dollar as may
reasonably be selected by Landlord and Tenant. Calculation of the adjusted Base
Monthly Rent shall be computed as follows: the rent payable for the Month
immediately preceding the Adjustment Date shall be multiplied by a fraction, the
denominator of which shall be the C.P.I. for the third Month prior to the
Commencement Date of the Lease (in the case of the first adjustment) or for the
third Month prior to the last Adjustment Date (for the second and subsequent
adjustments) and the numerator of which shall be the C.P.I. for the third Month
next preceding the current Adjustment Date. The rent so calculated shall be the
Calculated Adjustment to the Base Monthly Rent. Notwithstanding any other
provision of this Lease shall such new Base Monthly Rent (the Calculated
Adjustment) be less than the Base Monthly Rent payable for the Month immediately
preceding the then current Adjustment Date. Notwithstanding any other provision
of this Lease, the Calculated Adjustment shall never result in an annual
increase of less than 2.5% or more than 5% of the Base Monthly Rent used for
purposes of determining the then current Calculated Adjustment to the Base
Monthly Rent. The minimum and maximum adjustments shall be cumulative so that
the Base Monthly Rent shall be increased by not less than 7.5% nor more than 15%
as of each Adjustment Date.

                                        3
<PAGE>
     4.3. Mode of Payment. Tenant shall pay rent due Landlord at Landlord's
address set forth on the signature page of this Lease, or such other place as
Landlord may designate in writing.

     4.4. Additional Rent. Notwithstanding any other provision of this Lease,
if, during any Lease Year, the Property's Operating Expenses exceed Base Year
Operating Expenses, Tenant shall pay to Landlord, in addition to all other
payments due under this Lease, Tenants' Pro Rata Share of the amount by which
actual Operating Expenses for that year exceed Base Year Operating Expenses (the
"Excess Operating Expenses"). If during any Lease Year the amount by which Tax
and/or insurance premiums paid during such Lease Year exceed the amount paid for
such items in the Base Year, Tenant shall pay to Landlord as additional rent
the, its Pro Rata Share of the amount of the excess payments for such item over
the Base Year payments. Tenant's obligation to pay Excess Operating Expenses
shall be effective in every year during the Term. Nothing in this paragraph
shall entitle Landlord to double charge Tenant for Tenant's pro rata share of
Tax or insurance payments.

     4.5. Base Year Operating Expenses. Base Year Operating Expenses are actual
Operating Expenses incurred for the Property during the Base Year. Within three
months after the end of the Base Year, or as soon thereafter as may be
practical, Landlord shall deliver to Tenant a list of Base Year Operating
Expenses (the "Schedule"). The Schedule will fix the amount of the Base Year
Operating Expenses for all purposes under this Lease. If Tenant requests,
Landlord will provide Tenant with verification of amounts shown in the schedule.
If Landlord, for any reason, neglects or fails to timely provide the Schedule to
Tenant, such failure shall not be a default under or breach of this Lease,
neither shall it be deemed a waiver of any rights of Landlord to collect
Tenant's Pro Rata Share of Excess Operating Expenses, nor shall it excuse
Tenant's performance of any obligations under this Lease. Prior to the
Commencement of each Lease Year, Landlord shall deliver to Tenant Landlord's
good faith estimate of Excess Operating Expenses for the current Lease Year (the
"Estimated Excess"). Tenant shall pay its Pro Rata Share of Estimated Excess in
equal monthly installments throughout the then current Lease Year. Landlord
shall annually account for Excess Operating Expenses and Tenant's payment of its
Pro Rata Share of Excess Operating Expenses (the "Accounting"). Forthwith upon
the preparation of the Accounting, Landlord shall return to Tenant additional
rent paid against Tenant's Pro Rata Share of the Estimated Excess which exceeds
Tenant's Pro Rata Share of the actual Excess Operating Expenses for the year.
Forthwith upon the delivery to Tenant of the Accounting, Tenant shall pay to
Landlord any amount by which Tenant's Pro Rata Share of Excess Operating
Expenses for the year exceeds Tenant's payments against its Pro Rata Share.
Landlord may prepare the Accounting on the basis of the Lease Year or the
calendar year; if Landlord uses the calendar year, an adjustment will be made
for any portion of the calendar year that this Lease was not in effect. Landlord
estimates Base Year Operating Expenses for the items listed below as follows:
Property Taxes and Business Licenses - $49,296; Property and Liability Insurance
- - $8676; Maintenance $27,600; Management Fees - $37,200, Landscaping and
Security Services - $28,008. Each of the foregoing estimates reflects the
anticipated expenses for the Base Year. Landlord makes no warranty as to the
accuracy of such numbers; nor shall such numbers serve as a minimum or maximum
for such items for purposes of calculating the Base Year Operating Expenses.

     4.6. Security Deposit. Concurrent with Tenant's execution of this Lease,
Tenant shall deposit with Landlord $60,805.80 (the "Deposit"). Landlord shall
hold the Deposit as security for Tenant's faithful performance of all terms of
this Lease. Landlord may, at its option, apply the Deposit, or any portion of
the Deposit, to remedy defaults in the payment of rent or other charge
hereunder, to repair damages to the Premises caused by Tenant and its Agents,
and/or clean the Premises upon termination. If any portion of the Deposit is so
used or applied, Tenant shall, within 10 Days after written demand therefor,
deliver cash to Landlord in an amount sufficient to restore the Deposit to its
original amount. Tenant's failure to do so shall be a default under the terms of
this Lease. Landlord shall not be required to keep the Deposit separate from its
general funds; Tenant shall not receive interest on the Deposit. If Tenant fully
performs every provision of this Lease to be performed by it, the Deposit or any
balance thereof shall be returned to Tenant (or, at Landlord's option, to the
last assignee of Tenant's interest hereunder) following Tenant's surrender of
the Premises. In the event of a sale or transfer of Landlord's interest in this
Lease,

                                        4
<PAGE>
Landlord shall transfer the Deposit to its successor-in-interest, whereupon
Landlord shall be released from all liability for return of and/or accounting
for the Deposit.

     4.7. Late Charges. Tenant hereby acknowledges that late payment by Tenant
to Landlord of rent or other sums due hereunder will cause Landlord to incur
costs not contemplated by this Lease, the exact amount of which is extremely
difficult to ascertain. Such costs include, without limitation, processing,
accounting charges and late charges which may be imposed on Landlord by the
terms of any mortgage or trust deed covering the Property. Accordingly, if any
installment of Base Monthly Rent or any other sum due from Tenant shall not be
received by Landlord within 5 Days after the amount is due, Tenant shall pay to
Landlord a late charge equal to 5% of the overdue amount. The parties hereby
agree that such late charge represents a fair and reasonable estimate of the
costs Landlord will incur by reason of Tenant's late payment. Landlord's
acceptance of a late charge shall not constitute a waiver of Tenant's default
respecting the overdue amount or prevent Landlord from exercising any of the
remedies available hereunder.

5.   TAXES.

     5.1. Real and Personal Property Taxes. Landlord shall pay all real property
Tax and all Tax on personal property owned by Landlord relating to the Premises
and the Property. Nothing in this paragraph shall be so construed as to modify
Tenant's obligation to pay to Landlord Tenant's Pro Rata Share of any Tax in
excess of the Tax imposed during the Base Year.

     5.2. Taxes on Tenant's Property. Tenant shall pay before delinquency all
Tax levied or assessed on Tenant's fixtures, improvements, furnishings,
merchandise, equipment and personal property in and on the Premises, whether or
not affixed to the Property. If at any time after any Tax has become due or
payable, Tenant neglects to pay such Tax, Landlord shall be entitled, but not
obligated, to pay the same at any time thereafter and such amount so paid by
Landlord shall be repaid by Tenant to Landlord with Tenant's next rent
installment together with interest at the highest rate allowable by law.
Notwithstanding the foregoing, Tenant shall have the right to contest personal
property Tax assessed against Tenant.

6.   INSURANCE.

Nothing in this section shall be construed to modify Tenant's obligation to pay
Tenant's Pro Rata Share of insurance premiums in excess of the Base Year
premiums. Except as otherwise provided by this Lease, Tenant shall pay its Pro
Rata Share of all deductibles.

     6.1. Property Insurance. Landlord shall keep the Property insured for up to
100% of replacement value against damage by fire and risks normally included by
the insurance industry in the term "All Risk". Any recovery received from such
insurance shall belong to Landlord. Tenant shall have no claim to any portion of
any recovery under such policies.

     6.2. Fixtures. Tenant shall, at its sole expense, maintain insurance with
"All Risk" coverage on all fixtures, leasehold improvements, furnishings,
merchandise, equipment and personal property in or on the Premises in place as
of the date hereof and installed hereafter. Tenant shall maintain at its sole
cost any other types of insurance Tenant deems appropriate.

     6.3. Landlord's Liability Insurance. During the Term, Landlord shall
maintain a policy or policies of comprehensive general liability insurance with
combined single limit coverage of at least $2 million, insuring Landlord (and
others designated by Landlord, but excluding Tenant) against liability for
bodily injury, death and property damage on or about the Property.

     6.4. Tenant's Liability Insurance. Tenant shall, at its sole expense,
maintain for the mutual benefit of Landlord and Tenant, comprehensive general
liability and property damage insurance against claims for bodily injury, death
or property damage occurring in or about the Premises or arising out of the use
or occupancy of the Premises, with combined single limit coverage of not less
than $2 million. Such insurance shall include, without limitation, products
liability coverage for liability arising from the consumption of any food or
beverages sold at or from the Premises, and so-called host liquor and dram shop
liability coverage from liability arising from the consumption of alcoholic
beverages consumed at or sold from the Premises. The limits of such insurance
shall not limit Tenant's liability. Tenant shall furnish to Landlord prior to
the Commencement Date, and at least 30 Days prior to the expiration date of any
policy, certificates

                                        5
<PAGE>
indicating that the liability insurance required of Tenant is in full force and
effect, that Landlord has been named as an additional insured, and that no such
policy will be cancelled unless 30 Days' prior written notice of cancellation
has been given to Landlord. Said policies shall provide that Landlord, as an
additional insured, may recover for any loss suffered by Landlord by reason of
Tenant's negligence, and shall include a broad form liability endorsement.
Except as may be otherwise approved by Landlord in writing prior to the issuance
of such insurance policy, all insurance policies which Tenant is required to
obtain under the provisions of this Lease shall be obtained from companies with
a general policy rating of A+ or better as set forth in the most current issue
of "Best Insurance Guide" and a "AAA" rating by either Moody's Rating Service or
Standard & Poor's Rating Service. All insurance policies obtained by Tenant
pursuant to the requirement of this Lease shall be in a form satisfactory to
Landlord.

     6.5. Subrogation Waiver. Landlord and Tenant hereby release each other and
their respective Agents from any and all claims or demands of damage, loss,
expense or injury to the Premises, the Property, the furnishings and fixtures
and equipment or inventory or other property of either Landlord or Tenant in,
about or upon Property, which is caused by or results from perils, events which
are the subject of insurance carried by the parties in force at the time of such
loss; provided, however, that such waiver shall be effective only to the extent
permitted by the insurance covering such loss and to the extent insurance
coverage is not prejudiced thereby. Each party shall cause each insurance policy
it obtains to provide that the insurer waives all right of recovery by way of
subrogation against either party in connection with damage covered by such
policy.

     6.6. Indemnification. Except in the case of Landlord's intentional
misconduct or negligence, Tenant will indemnify Landlord and save it harmless
from and against any and all claims, actions, damages, liability and expense in
connection with loss of life, personal injury and/or damage to property arising
from or out of any occurrence in, upon or at the Premises, or the occupancy or
use by Tenant of the Property or any part thereof, or occasioned wholly or in
part by any acts or omissions of Tenant, its Agents, contractors, employees,
servants, licensees or concessionaires or by anyone permitted to be on the
Premises by Tenant (collectively "Tenant and its Agents"). If Landlord shall be
made a party to any such litigation commenced by or against Tenant, Tenant shall
protect and hold Landlord harmless from all claims, liabilities, costs and
expenses, and shall pay all costs, expenses and reasonable legal fees incurred
by Landlord in connection with such litigation. If Tenant is made a party to any
litigation commenced by or against Landlord solely as a result of Landlord's
intentional misconduct or Landlord's negligence, Landlord shall defend and
indemnify Tenant against the costs of such litigation. As used herein,
"litigation" includes arbitration. Nothing in this paragraph shall limit or
prevent the application of the doctrine of comparative negligence; and in the
event of negligence by Landlord and Tenant, each party shall bear responsibility
for a proportionate share of the damages based upon the doctrine of comparative
negligence.

     6.7. Plate Glass Replacement. If any glass in and about the Premises is
damaged or broken by cause other than the acts of Landlord and its Agents,
Tenant shall pay Landlord's cost of replacement, provided that such amount shall
not exceed the deductible then in effect on Landlord's insurance policy, if any,
covering the damaged glass. Nothing herein shall be construed to require
Landlord or Tenant to carry plate glass insurance.

     6.8. Worker's Compensation. Tenant shall, at its sole expense, keep in
force worker's compensation insurance and other insurance to comply with all
applicable Regulations.

7.   MAINTENANCE.

Nothing in this paragraph shall modify Tenant's obligation to pay its Pro Rata
Share of Excess Operating Expenses.

     7.1. Premises. Tenant shall repair all damage to the interior of the
Premises and keep the Premises in good order, condition and repair. Tenant's
obligations include all interior walls, doors, doorways, lighting fixtures,
plumbing fixtures, and all windows located in the Premises. Tenant waives the
provisions of any law permitting repairs by a tenant at the expense of a
landlord, including, without limitation, California Civil Code ss.ss. 1941
through 1946, inclusive.

                                        6
<PAGE>
     7.2. Common Areas and Systems. Landlord shall maintain the Common Areas of
the Property in good order and condition. Notwithstanding the foregoing,
Landlord shall repair damage occasioned by the acts of Tenant and its Agents at
Tenant's sole expense. Tenant shall notify Landlord, in writing, of necessary
repairs or maintenance to Common Areas and systems and Landlord shall make
necessary repairs within a reasonable time. Landlord shall keep improvements
upon the Property, including all sewer connections, plumbing, heating and
cooling appliances, wiring, HVAC and landscaping in good order and repair
including the replacement of such improvements, appurtenances and landscaping
when necessary. The manner of maintenance and repair of the Property shall be at
Landlord's sole and absolute discretion. Maintenance and repairs will be
completed in a good and workmanlike manner. Landlord shall make commercially
reasonable efforts to perform maintenance and repairs expeditiously and attempt
to minimize interference with Tenant's normal business operations. Landlord will
furnish garbage collection and janitorial services to the Property in a manner
that such services are customarily furnished to comparable buildings in the
area. Nothing in this paragraph modifies Tenant's obligation to pay its Pro Rata
Share of the Property's Excess Operating Expenses to Landlord.

     7.3. Alterations, Changes and Additions by Tenant. Tenant shall make no
Alteration to any portion of the Property without Landlord's prior written
consent. As a condition to consent, Landlord may require that Tenant remove such
Alterations at the expiration of the Term and restore the Premises and Property
to their condition prior to the Alteration. As a further condition to consent,
Landlord may require Tenant to provide Landlord, at Tenant's sole expense, with
a lien and completion bond in an amount equal to 100% of the estimated cost of
the Alteration to insure Landlord against any liability for mechanic's and
materialman's liens and to ensure completion of the Alteration. Each Alteration
shall be under the supervision of a competent architect or competent licensed
structural engineer and made in accordance with plans and specifications
furnished to and approved by Landlord prior to the commencement of work. In the
event that any Alteration increases the floor area of the Premises, the Base
Monthly Rent and Tenant's Pro Rata Share shall be proportionately increased.
Tenant shall provide 14 Days written notice to Landlord of the date on which
construction of each Alteration will commence in order to permit Landlord to
post a notice of nonresponsibility. Each Alteration shall be constructed in a
good and workmanlike manner in accordance with all Regulations relating to such
construction. Every Alteration shall remain for the benefit of and become the
property of Landlord, unless Landlord requires its removal by giving Tenant
written notice at least 30 Days before the date Tenant is to vacate the
Premises, in which case, Tenant shall remove the Alteration(s) and restore the
Premises to their pre-Alteration condition.

     7.4. Use of Plumbing, Electrical and HVAC Systems. Tenant shall not use the
plumbing, electrical facilities or heating and air conditioning ("HVAC") systems
for any purpose other than that for which they were constructed. Tenant shall
bear the expense of repair of any breakage, stoppage or other damage relating to
the plumbing, electrical and/or HVAC systems resulting from the actions of
Tenant and its Agents.

     7.5. Liens. Tenant shall keep the the Property free from liens arising from
work performed, material furnished or obligations incurred by Tenant. Tenant
shall indemnify, hold harmless and defend Landlord from all liens and
encumbrances arising from work performed or materials furnished by or at
Tenant's direction and all actions relating to such liens. In the event that
Tenant shall not, within 20 Days following Tenant becoming aware of the
imposition of any such lien, cause such lien to be released of record by payment
or posting of a proper bond, Landlord shall, in addition to all other remedies
provided herein and by law, have the right, but not the obligation, to cause the
same to be released by such means as it shall deem proper, including payment of
the claim. All expenses incurred by Landlord in connection therewith, including
attorneys' fees and costs, shall be paid to Landlord by Tenant on demand with
interest at the highest rate allowable by law from the date paid by Landlord to
the date of Tenant's reimbursement to Landlord. Landlord shall have the right at
all times to post and keep posted on the Premises any notices permitted or
required by law, or which Landlord shall deem proper, for the protection of
Landlord and the Property.

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<PAGE>
8.   MANAGEMENT.

The Wareham Property Group, Inc., an affiliate of Landlord, or another
affiliated or unaffiliated third party, will be hired as property manager.

9.   UTILITIES AND SERVICES.

Nothing in this paragraph modifies Tenant's obligation to pay its Pro Rata Share
of Excess Operating Expenses.

     9.1. Premises. Landlord shall make available to the Premises water,
electricity for normal office use (including desk top office equipment and
normal copying equipment) at all times. Landlord shall provide to the Premises
heating, ventilation and air-conditioning ("HVAC") as required in Landlord's
reasonable judgment for the comfortable use and occupancy of the Premises during
the hours of 8:00 a.m. to 6:00 p.m., Monday through Friday (national holidays
excluded) (hereafter "Standard Business Hours"). If Tenant desires HVAC at any
other time than Standard Business Hours, Landlord will furnish the same to
Tenant on reasonable notice from and at a reasonable charge to Tenant. If
Tenant's use of the Premises requires additional electrical power beyond the
power described above ("Supplemental Electrical Power"), Landlord shall make
commercially reasonable efforts to make such Supplemental Electrical Power
available to Tenant. Tenant shall pay in full all costs associated with
modifications to the electrical system servicing the Property to make such
Supplemental Electrical Power available. Tenant shall not, without Landlord's
written consent, use any device in the Premises which consumes more electricity
than is usually furnished or supplied for use of Premises as general office
space, as determined by Landlord. Tenant shall not connect any apparatus with
electric current except through existing electrical outlets in the Premises. If
Tenant uses heat generating equipment in the Premises, which affects the
temperature otherwise maintained by the HVAC system, the cost of supplementary
air-conditioning units, including the cost of installation, operation and
maintenance thereof, shall be paid by Tenant to Landlord within 10 Days after
receipt of an invoice. Throughout the Term, Landlord shall pay all "Utility
Charges" (defined as charges for gas and electricity provided to the Premises).
For each month of the Term, Tenant shall reimburse Landlord for all Utility
Charges paid by Landlord respecting the Premises in excess of $.13 per square
foot per Month of the Premises ($4272.84 per month). The reimbursement referred
to in the preceding sentence shall be made by Tenant to Landlord on a quarterly
basis at the end of each calendar quarter of every year of the Term and within
10 Days of Tenant's receipt of Landlord's billing for such reimbursement. The
provisions of this paragraph respecting Tenant's reimbursement of Utility
Charges for the Premises supersede all other provisions of this Lease respecting
payment of that portion of Operating Expenses consisting of Utility Charges. In
the event that the Premises are not separately metered, Landlord shall equitably
allocate Utility Charges incurred for the Property in order to determine that
portion of the Utility Charges attributable to the Premises in accordance with
the provisions of this paragraph.

     9.2. Common Areas. Landlord shall provide utilities, landscaping,
janitorial and, if Landlord deems it necessary or appropriate, security services
for the Common Area.

     9.3. Limitation of Liability. Landlord shall not be in breach of this Lease
or be liable for damages directly or indirectly resulting from the following
conditions: (1) interruption of use of equipment in connection with the
furnishing of any of the services described in this section 9; (2) failure to
furnish or delay in furnishing such services caused by accident or any condition
or event beyond Landlord's reasonable control; (3) limitation, curtailment or
rationing of, or restrictions on, use of water, electricity, gas or any other
form of energy serving the Property. Landlord shall not be liable for loss of or
injury to property or business, however occurring, through or in connection with
or incidental to failure to furnish any such services. Notwithstanding the
foregoing, however, in the event of a deprivation of electrical services to the
Premises for a continuous period of 30 Days for any reason other than the acts
of Tenant and its Agents, Tenant shall have the right to abate the payment of
Base Monthly Rent falling due thereafter and until such service is restored to
the Premises.

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10. USE OF PREMISES.

     10.1. Use. Tenant shall use the Premises for general office purposes and
for no other purposes whatsoever.

     10.2. Suitability. This Lease is subject to all applicable Regulations
governing the use of the Property. Tenant has not entered into this Lease in
reliance upon any representation or warranty of Landlord or its Agents as to
suitability of the Premises for the conduct of Tenant's business. Tenant has
made its own analysis of the Premises suitability for Tenant's intended use.

     10.3. Uses Prohibited.

     10.3.1. Rate of Insurance. Tenant shall not do or permit anything to be
done in or about the Premises which will cause the existing rate of insurance
for the Property to increase or cause cancellation of any insurance policy
covering the Property; nor shall Tenant sell or permit to be kept, used or sold
in or about the Property any articles which may be prohibited by a standard form
policy of fire insurance. Tenant shall pay to Landlord, as additional rent, the
full amount of any increased premium resulting from Tenant's use of the
Premises.

     10.3.2. Interference with Other Tenants. Tenant shall not do or permit
anything to be done in or about the Property which will in any way obstruct or
interfere with the rights of other tenants or occupants of the Property or
injure or annoy them, neither shall Tenant cause, maintain or permit any
nuisance in or about the Property. Tenant shall not commit or suffer to be
committed any waste in or upon the Property.

     10.3.3. Applicable Laws. Tenant shall not use the Premises in violation of
any applicable Regulations or permit anything to be done in or about the
Property which will violate or conflict with any Regulation. Tenant shall, at
its sole cost and expense, comply with all Regulations and with the requirements
of any board of fire underwriters or other similar body now or hereafter
constituted relating to the condition, use and occupancy of the Premises. The
judgment of a court of competent jurisdiction or Tenant's admission in any
action, whether Landlord be a party thereto or not, that Tenant violated a law,
statute, ordinance or government rule, regulation or requirement, shall be
conclusive of that fact between Landlord and Tenant.

     10.3.4. Auctions. Tenant shall not conduct or allow any auction or similar
sale upon the Property.

11.  DEFAULTS AND REMEDIES.

     11.1. Tenant's Default. Each of the following events is a default and
breach of this Lease by Tenant: (a) Tenant's failure to pay any rent or charges
required to be paid by Tenant under this Lease; (b) Tenant's abandonment or
vacation of the Premises; (c) Tenant's failure to promptly and fully perform any
other covenant, condition or agreement contained in this Lease where such
failure continues for 14 Days after written notice from Landlord to Tenant of
such default; (d) the levy of a writ of attachment or execution on this Lease or
on any of Tenant's property located in the Premises; (e) a general assignment
for the benefit of Tenant's creditors or an arrangement, composition, extension
or adjustment with Tenant's creditors, the filing by or against Tenant of a
petition for relief or other proceeding under the federal bankruptcy laws or
state or other insolvency laws, or the assumption by any court or administrative
agency, or by a receiver, trustee or custodian appointed by either, of
jurisdiction, custody or control of the Premises or of Tenant or any substantial
part of its assets or property; or (f) if the interest of Tenant under this
Lease is held by a partnership or by more than one person or entity, the
occurrence of any act or event described in part (e) above in respect of any
partner in the partnership or any person or entity holding an interest in Tenant
of 25% or more. In the event a nonmonetary default occurs which cannot
reasonably be cured within the above time period but Tenant commences corrective
action within said period, Tenant shall not be subject to penalty under this
Lease if it prosecutes the corrective action diligently and continuously to
completion and completes the corrective action within 90 Days of the
commencement of the corrective action.

     11.2. Landlord's Remedies. If Tenant defaults under this Lease, in addition
to other rights or remedies Landlord may have under this Lease or the law,
Landlord may elect either of the remedies set forth in paragraphs 11.2.1 and
11.2.2 of this Lease. Notwithstanding any other provision of this Lease,
Landlord has the remedy described in California Civil Code ss.1951.4 and

                                        9
<PAGE>
Landlord may continue this Lease in effect after Tenant's breach and abandonment
and recover rent as it becomes due. For purposes of this paragraph 11 (inclusive
of all subparagraphs), "worth at the time of award" of the amounts referred to
in parts 11.2.1(i) and 11.2.2(ii) shall be computed by allowing interest at the
highest rate allowable by law, and "worth at time of award" of the amount
referred to in part 11.2.1(iii) shall be computed by discounting such amount at
the rate specified in California Civil Code ss.1951.2(b) or any successor
statute. In such computations, the rent due hereunder shall include Base Monthly
Rent plus the aggregate amount of all other rentals, charges and other amounts
payable by Tenant hereunder.

     11.2.1. Landlord, at its option, shall have the right to immediately
terminate this Lease and Tenant's right to possession of the Premises by giving
written notice to Tenant and to recover from Tenant an award of damages equal to
the sum of (i) the worth at the time of award of the unpaid rental which had
been earned at the time of termination, (ii) the worth at the time of award of
the amount by which the unpaid rental which would have been earned after
termination until the time of award exceeds the amount of such rental loss that
Tenant affirmatively proves could have been reasonably avoided, (iii) the worth
at the time of award of the amount by which the unpaid rental for the balance of
the Term after the time of award exceeds the amount of such rental loss that
Tenant affirmatively proves could be reasonably avoided, (iv) any other amount
necessary to compensate Landlord for all the detriment either proximately caused
by Tenant's failure to perform Tenant's obligations under this Lease or which in
the ordinary course of things would be likely to result therefrom, and (v) all
such other amounts in addition to or in lieu of the foregoing as may be
permitted from time to time under applicable law; or

     11.2.2. Landlord has the remedy described in California Civil Code Section
1951.4 (Landlord may continue lease in effect after Tenant's breach and
abandonment and recover rent as it becomes due, if Tenant has the right to
sublet or assign, subject only to reasonable limitations).

     11.3. Landlord's Default. Except as otherwise provided by this Lease,
Landlord's failure to perform any obligation required of Landlord (other than a
delay in delivery of possession provided for in paragraph 3.2) within 30 Days
after Tenant's delivery to Landlord of written notice, specifying wherein
Landlord has failed to perform such obligation shall constitute a default; if,
however, the nature of the obligation is such that more than 30 Days are
required for performance, then Landlord shall not be in default if it commences
performance within such 30 Day period and diligently prosecutes the same to
completion.

12.  EXPIRATION OR TERMINATION.

     12.1. Surrender of Possession. On expiration or other termination
(hereafter collectively "Termination") of this Lease, Tenant shall surrender to
Landlord possession of the Premises and all improvements thereon, subject to the
provisions of paragraph 7.3 above, in as good order and condition as when
possession was taken by Tenant excepting only ordinary wear and tear. On
Termination, Landlord may reenter the Premises and remove all persons and
property thereon. If Tenant fails to remove any effects that it is required or
entitled to remove from the Premises on Termination, Landlord may remove the
same and, at its option, store or dispose of them. Tenant shall pay Landlord on
demand all expenses incurred in such removal and in making the Premises free
from all dirt, litter, debris and obstruction, including all storage and
insurance charges. If the Premises are not surrendered at the end of the Term,
Tenant shall indemnify Landlord against loss or liability of resulting from
Tenant's delay in surrendering the Premises, including, without limit, claims
made by succeeding tenants based on such delay.

     12.2. Holding Over. If Tenant, with Landlord's consent, remains in
possession of the Premises after Termination and if Landlord and Tenant have not
executed a written agreement as to such holding over, then such occupancy shall
be a tenancy from month to month at a Base Monthly Rent of 110% of the Base
Monthly Rent in effect immediately prior to Termination and such other payments
to be made as herein provided. In the event of holding over, all provisions of
this Lease shall remain in effect on said month to month basis. If Tenant
remains in possession of the Premises after Termination without Landlord's
consent, the monthly fair market rental value of the

                                       10
<PAGE>
Premises for the duration of such holding over shall be deemed to be 110% of the
Base Monthly Rent payable for the last Month of the Term.

     12.3. Voluntary Surrender. The voluntary or other surrender of this Lease
by Tenant, if accepted by Landlord, or a mutual cancellation hereof, shall not
work a merger, but shall, at Landlord's option, terminate any existing
subtenancies, or operate as an assignment to Landlord of any such subleases.

13.  CONDEMNATION OF PREMISES.

     13.1. Total Condemnation. If the entire Premises shall be taken by
Condemnation at any time during the Term, this Lease shall terminate as of the
date transfer of possession is required. All rent shall be paid up to the
Termination, and Tenant shall have no claim against Landlord for the value of
any unexpired portion of the Term.

     13.2. Partial Condemnation. If any portion of the Premises is taken by
Condemnation during the Term, this Lease shall remain in full force and effect;
except that in the event a partial taking leaves the Premises unsuitable for
occupation, Tenant shall have the right to terminate this Lease effective upon
the date transfer of possession is required unless Landlord makes other
arrangements to replace Tenant's space. Landlord and Tenant shall each have the
right to terminate this Lease effective on the date transfer of possession is
required if more than 50% of the total square footage of the Premises taken by
Condemnation. Tenant and Landlord may elect to exercise their respective rights
to Terminate this Lease pursuant to this paragraph by serving written notice to
the other within 30 Days of their receipt of notice of Condemnation, except that
Tenant's notice shall be ineffective if within 10 Days of Tenant's delivery of
notice to Landlord, Landlord serves notice upon Tenant of Landlord's election to
provide alternate space equivalent to that condemned. Tenant shall have the
right to approve such replacement space. All rent and other obligations of
Tenant under this Lease shall be paid up to the date of Termination, and Tenant
shall have no claim against Landlord for the value of any unexpired portion of
the Term. If this Lease is not cancelled, the Base Monthly Rent after such
partial taking shall be that percentage of the adjusted Base Monthly Rent
provided for by this Lease, equal to the percentage which the square footage of
the untaken part of the Premises immediately after the taking plus such
replacement square footage as Landlord may make available to Tenant bears to the
square footage of the Premises immediately before the taking. Tenant's Pro Rata
Share shall be adjusted to reflect any change in the square footage of the
Premises.

     13.3. Award to Tenant. In the event of any Condemnation, Tenant shall have
the right to claim and recover from the condemning authority compensation as may
be separately recoverable by Tenant for loss of business, Tenant's relocation
expenses, fixtures or equipment belonging to Tenant immediately prior to the
Condemnation. The balance of any Condemnation award shall belong to Landlord,
and Tenant shall have no further right to recover from Landlord or the
condemning authority for any additional claims arising out of such taking.

     13.4. Waiver of Partial Termination Rights. Tenant waives the provisions of
California Code of Civil Procedure Section 1265.130.

14.  ENTRY BY LANDLORD.

Tenant shall permit Landlord and its Agents to enter the Premises at all
reasonable times for any of the following purposes: to inspect the Premises; to
make such repairs, alterations or additions to the Premises and/or to any other
portion of the Property as Landlord is obligated or may elect to make; to post
"To Lease" signs for the purposes of reletting during the last 120 Days of the
Term, to show the Premises as part of a prospective lease or sale by Landlord
and/or to post notices of nonresponsibility. Landlord shall have such right of
entry without any rebate of rent to Tenant for any loss of occupancy or quiet
enjoyment of the Premises thereby occasioned. Notwithstanding the foregoing,
Landlord shall provide 24 hours advance notice to Tenant of intended entry
except under circumstances of an emergency.

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<PAGE>
15.  LIABILITY LIMITATION AND INDEMNIFICATION.

The provisions of this section 15 supersede every other provision of this Lease
to the extent that they are inconsistent with such other provisions.

     15.1. Limitation of Landlord's Liability. Tenant shall not hold Landlord
liable for any amount in excess of insurance coverage maintained by Landlord
pursuant to paragraph 6.3 of this Lease ("Existing Coverage") with respect to
any injury or damage, either proximate or remote, occurring through or caused by
any repairs or Alterations to the Property, unless such injury or damage arises
from Landlord's negligence, willful misconduct, reckless disregard of Landlord's
duties or breach of this Lease. Landlord shall not be liable in excess of
Existing Coverage for any injury or damage occasioned by defective electric
wiring, or the breaking, bursting, stoppage or leaking of any part of the
plumbing, air-conditioning, heating, fire control sprinkler systems or gas,
sewer or steam pipes, unless such injury or damage arises from Landlord's
negligence, willful misconduct or reckless disregard of Landlord's duties or
breach of this Lease.

     15.2. Limitation on Enforcement of Judgments. Notwithstanding any other
provision of this Lease, and with the exception of a Judgment in Tenant's favor
against Landlord in which there is a finding of actual fraud in the inducement
by Landlord, Tenant and its Agents shall, under all circumstances be absolutely
limited to Landlord's estate in the Property for satisfaction of Tenant and its
Agents' remedies, and/or for the collection of a judgment, court order or
arbitration award requiring the payment of money by Landlord as the result of
any and all judgments, orders and awards relating to or arising out of Tenant
and its Agents occupancy and use of the Property and/or in the event of any
default by Landlord hereunder. No other property or assets of Landlord or its
partners or principals, disclosed or undisclosed, shall be subject to levy,
execution or other enforcement procedure for the satisfaction of Tenant and its
Agents' remedies under or with respect to this Lease, the relationship of
Landlord and Tenant hereunder, or the use and occupancy of the Property and the
Premises by Tenant and its Agents. Tenant, on behalf of itself and its Agents
expressly waives any and all right to collect or enforce any and all orders,
awards and/or judgments against Landlord in excess of the limitations imposed by
this paragraph. Tenant shall require that each subtenant of Tenant and each
assignee of Tenant agree to be bound by the waiver set forth in this paragraph.
The Landlord's maximum exposure as set forth in this paragraph is cumulative (as
to judgments, awards and orders against Landlord in connection with this Lease,
the relationship of Landlord and Tenant hereunder, or the use and occupancy of
the Property by Tenant and its Agents). The limits imposed by this paragraph
also apply to any and all duties of indemnity (express and/or implied) owed by
Landlord to Tenant. As used in this paragraph, references to "Landlord" include
all persons and entities who now or hereafter own or may own an interest in
Landlord.

16.  ASSIGNMENT AND SUBLETTING.

     16.1. Generally. Tenant shall not directly or indirectly assign this Lease
in whole or in part, sublet any part of the Premises, license the use of any
part of the Premises or any business conducted thereon, or encumber or
hypothecate this Lease, without first obtaining Landlord's written consent which
consent Landlord shall not unreasonably withhold. The sale or other transfer of
shares of stock, partnership interests or other ownership interests in Tenant
resulting in a change in the effective control of Tenant, or any merger,
consolidation or other reorganization of Tenant other than one with a comparable
or greater financial position shall be regarded as an indirect assignment of
Tenant's interest in this Lease. Tenant's request for consent to any assignment,
sublease or other transfer shall be in writing and shall include the following:
(a) the name and legal composition of the proposed transferee; (b) the nature of
the proposed transferee's business to be carried on in the Premises; (c) the
Terms and provisions of the proposed assignment or sublease; and (d) such
financial and other reasonable

                                       12
<PAGE>
information as Landlord may request concerning the proposed transferee or
concerning the proposed assignment or sublease and any transaction contemplated
to occur in connection therewith. Any assignment, subletting, licensing,
encumbering or hypothecating of this Lease without Landlord's prior written
consent shall constitute a default entitling Landlord to exercise all rights and
remedies herein provided. Landlord's consent to any assignment or sublease shall
not constitute a waiver of the necessity for such consent to any subsequent
assignment or sublease. The prohibition against assignment and subletting
contained in this paragraph includes a prohibition against assignment or
subletting by operation of law. Notwithstanding any assignment or subletting
with Landlord's consent, Tenant shall remain fully liable on this Lease and
shall not be released from its obligations hereunder. Without limiting other
reasons or circumstances, Landlord and Tenant agree that it is reasonable for
Landlord to withhold consent to an assignment or sublease, if (i) the financial
strength of the proposed assignee or sublessee is not, in Landlord's reasonable
judgment, commensurate with the obligations of the Lease; (ii) the proposed
assignee's or sublessee's use would, in Landlord's reasonable judgment, be
incompatible with the then current tenants, or use of the rest of the Property;
or (iii) the proposed assignee's or sublessee's use would generate traffic,
parking and/or wear and tear on the Premises or Property materially in excess of
that generated by Tenant's use.

     16.2. Tenant's Payments. If Landlord consents to a sublease or assignment,
Tenant shall pay Landlord's reasonable attorneys' fees incurred in connection
with giving such consent. Tenant shall also pay Landlord 50% of all Excess Rent
received by Tenant directly or indirectly in respect of an assignment of this
Lease or sublease of the Premises. As used in this Lease, "Excess Rent" means,
in the case of an assignment, all consideration so received and, in the case of
a sublease, all consideration so received in excess of rents and charges
reserved under this Lease. The assignee or sublessee shall, on assuming Tenant's
obligations under this Lease, become jointly and severally liable to Landlord
for the payment of Landlord's share of Excess Rent.

17.  DAMAGE OR DESTRUCTION.

     17.1. Right to Terminate on Destruction of Premises. Landlord and Tenant
each have the right to terminate this Lease if the Premises or the Building are
damaged to an extent exceeding 50% of the then replacement cost of the Premises
(in the event of damage limited to the Premises) or 33% of the Building (in the
event of damages not limited to the Premises). Landlord shall also have the
right to terminate this Lease if the Premises or the Building are damaged by an
uninsured peril to an extent exceeding 33% of the then replacement cost of the
Premises (in the event of damage limited to the Premises) or 25% of the Building
(in the event of damages not limited to the Premises). If a party elects to
terminate under the provisions of this section, the terminating party shall
deliver written notice to the non-terminating party within 30 Days of the
occurrence of the damage. Tenant shall have a minimum of 30 Days to vacate the
Premises unless they are unsafe for occupancy, in which case, Tenant shall
immediately vacate the Premises.

     17.2. Repairs by Landlord. If this Lease is not terminated pursuant to
paragraph 17.1, Landlord shall immediately upon receipt of insurance proceeds
paid in connection with such casualty, but no later than 90 Days after the
damage has occurred, proceed to repair the Premises and/or the Building, on the
same plan and design as existed immediately before such damage occurred, subject
to such delays as may be reasonably attributable to governmental restrictions,
failure to obtain materials, labor, or other causes beyond Landlord's control.
Tenant shall pay the cost of repair and replacement of all fixtures, leasehold
improvements, furnishings, merchandise, equipment and Tenant's personal property
not covered by insurance.

     17.3. Reduction of Rent During Repairs. Except with respect to damage
caused in whole or in part by Tenant and its Agents, if Tenant is able to
continue to conduct its business during the making of repairs, the Base Monthly
Rent will be equitably reduced in the proportion that the unusable part of the
Premises bears to the whole thereof for the period of repairs. No rent shall be
payable while the Premises are wholly unusable due to casualty damage except for
casualty damage caused in whole or in part by Tenant and its Agents. Tenant
shall remain liable for all rent falling due in the period of repair of damages
caused in whole or in part by Tenant and its Agents.

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<PAGE>
     17.4. Waiver. Tenant waives ss.ss. 1932, subdivision 2, and 1933,
subdivision 4, of the Civil Code of California.

     17.5. Landlord's Overriding Right to Terminate. Notwithstanding anything to
the contrary herein, if the discounted present value of the Base Monthly Rent
due hereunder for the balance of the Term, using as the discount rate the prime
commercial lending rate in effect at the Bank of America, NT&SA, as of the date
Landlord is to commence repairs pursuant to paragraph 17.2 of this Lease, is
less than the cost of repairing the damage to the Premises, Landlord may, at its
option, terminate this Lease on 10 Days' written notice to Tenant.

18.  Hazardous Materials

     18.1. Tenant's Obligations.

     18.1.1. Restrictions on Hazardous Materials. Tenant and its Agents shall
not cause or permit "Hazardous Material" (as defined below) to be brought upon,
used, handled, disposed of, transported, kept, manufactured, generated or stored
(hereafter collectively "Handled" or "Handling") in, on, about or under the
Property without Landlord's prior written consent.

     18.1.2. Applicable Regulations. If any Hazardous Material is Handled in,
on, about or under the Property by Tenant and its Agents, then Tenant shall bear
all financial and other responsibility for ensuring that such material is used,
kept and stored in compliance with all Regulations and Environmental, Health and
Safety Requirements respecting Handling of such Hazardous Material and with the
highest standards prevailing in the industry for the Handling of such Hazardous
Material. Without limiting Tenant's other obligations as set forth in this
Lease, Tenant shall, at its own cost and expense, procure, maintain in effect
and comply with all conditions and requirements of any and all permits, licenses
and other governmental and regulatory approvals or authorizations required under
any and all applicable Regulations and Environmental, Health and Safety
Requirements relating to the Handling of such Hazardous Material by Tenant and
its Agents in, on or about the Property. Tenant will provide Landlord copies of
all permits, licenses, or other regulatory approvals or authorizations within 5
business Days of receipt thereof.

     18.1.3. Restoration. If, as a result of actions caused or permitted by
Tenant and its Agents, the presence of Hazardous Material in, on, about or under
the Property or any adjoining property, existing during the Term of this Lease
and/or subsequent to the Term of this Lease results in any contamination of the
Property or the surrounding environment; Tenant shall promptly take all actions
at its sole cost and expense as are necessary to return the Property and/or the
other affected property to the condition existing prior to such contamination
("Restoration"); provided, however, that Tenant shall not undertake any
Restoration respecting the Property without first providing Landlord with
written notice thereof and obtaining Landlord's approval. Tenant shall carry out
any approved Restoration in a manner which complies with all Environmental,
Health and Safety Requirements. Tenant shall not undertake any Restoration, nor
enter into any settlement agreement, consent decree or other compromise with
respect to any claims, relating to any Hazardous Material in any way connected
with the Property without first notifying Landlord of Tenant's intention to do
so and affording Landlord ample opportunity to appear, intervene or otherwise
appropriately assert and protect Landlord's interests.

     18.1.4. Removal. Upon Termination, Tenant shall cause to be removed from
the Property all Hazardous Material existing in, on, about or under the Property
Handled by Tenant and its Agents and shall cause such Hazardous Material to be
stored, treated, transported and/or disposed of in compliance with all
applicable Regulations and Environmental, Health and Safety Requirements. Any
Hazardous Material which Tenant causes to be removed from the Property shall be
removed solely by duly licensed haulers and transported to and disposed of at
duly licensed facilities for the final disposal of such Hazardous Material.
Tenant shall deliver to Landlord copies of any and all manifests and other
documentation relating to the Handling of any Hazardous Material reflecting the
legal and proper removal, storage, treatment, transportation and/or disposal
thereof. Tenant shall, at its sole cost and expense, repair any and all damage
to the Property resulting from Tenant and its Agents removal of such Hazardous
Material. Tenant's obligation to pay rent shall continue until Tenant completes
such removal and effects such repairs.

                                       14
<PAGE>

     18.1.5. Tenant's Written Confirmation. Tenant shall, from time to time
throughout the Term, execute such affidavits, certificates or other documents as
Landlord may request concerning Tenant's best knowledge and belief regarding the
presence of Hazardous Material in, on, about or under the Property. Further,
each year throughout the Term on the anniversary of the Commencement Date,
Tenant shall deliver to Landlord a letter stating that during the preceding year
Tenant has complied with the provisions of this Section 18 or, if Tenant has not
so complied, a letter setting forth the details of noncompliance.

     18.1.6. Tenant's Duty to Notify Landlord. Tenant shall notify Landlord in
writing immediately on becoming aware of: (1) any enforcement, cleanup,
remediation or other action threatened, instituted or completed by any
governmental or regulatory agency or private person with respect to the Property
or any adjoining property relating to Hazardous Material; (2) any claim
threatened or made by an person against Tenant, the Landlord, the Property or
any adjoining landowner, tenant or property for personal injury, compensation or
any other matter relating to Hazardous Material; and (3) any reports made by or
to any governmental or regulatory agency with respect to the Property or any
adjoining property relating to Hazardous Material, including without limitation,
any complaints, notices or asserted violations in connection therewith Further,
Tenant shall also supply to Landlord as promptly as possible, and in any event
within five Days after Tenant first receives or sends the same, copies of all
claims, reports, complaints, notices, warnings, asserted violations or other
documents relating in any way to the foregoing.

     18.2. Landlord's Rights. Landlord and its Agents and representatives shall
have the right to communicate, verbally or in writing, with any governmental or
regulatory agency or any environmental consultant on any matter with respect to
the Property relating to Hazardous Material. Landlord shall be entitled to
copies of any and all notices, inspection reports or other documents issued by
or to any such governmental or regulator agency or consultant with respect to
the Property relating to Hazardous Material.

     18.3. Tenant's Duty to Indemnify. If the Handling by Tenant and its Agents
of Hazardous Material on or about the Premises results in contamination of the
Property and/or the surrounding environment, or if any lender or governmental
agency requires an investigation to determine whether there has been any
contamination of the Property or any adjoining property as a result of such use
or storage of Hazardous Material by Tenant and its Agents, then Tenant shall
indemnify, defend and hold Landlord all partners or other affiliates of
Landlord, and all directors, officers, shareholders, employees, Agents,
contractors, attorneys and/or partners of any of the foregoing harmless from any
and all claims, damages, penalties, fines, costs, liabilities and losses
(including, without limitation, diminution in value of the Property, damages for
the loss or restriction on use of rental or usable space or of any other amenity
of the Property, damages arising from any adverse impact on marketing of space
in the Property, other consequential damages and sums paid in settlement of
claims, attorneys' fees, consultants' fees and experts' fees) which arise during
or after the Term as a result of such contamination. Tenant's indemnification of
Landlord includes, without limitation, costs incurred in connection with removal
or Restoration required by any governmental or regulatory agency and/or private
persons because of the presence of Hazardous Material in the soil or groundwater
in, on, about or under the Property or any adjoining property as a result of the
acts of Tenant and its Agents and any and all legal fees and expenses incurred
by Landlord with respect to such claims, demands, investigations and responses.

     18.4. Right of Entry. If contamination of the Property by Hazardous
Material occurs or if any lender or governmental agency requires an
investigation to determine whether there has been any contamination of the
Property or any adjoining property, then Landlord and its Agents shall have the
right, at any reasonable time and from time to time to enter upon the Property
to perform monitoring, testing or other analyses, and to review all applicable
documents, notices, correspondence or other materials. If contamination resulted
from the conduct of Tenant and its Agents, Tenant shall pay all costs and
expenses reasonably incurred by Landlord in connection with such investigation,
monitoring, and testing. Such sums shall be due and payable by Tenant when
Landlord delivers its invoice to Tenant for such charges.

     18.5. Definitions. The following terms shall have the following meanings:

                                       15
<PAGE>
     18.5.1. "Hazardous Material" means, without limitation, (1) petroleum or
petroleum products; (2) hydrocarbon substances of any kind; (3) asbestos in any
form; (4) formaldehyde; (5) radioactive substances; (6) industrial solvents; (7)
flammables; (8) explosives; (9) leakage from underground storage tanks; (10)
substances defined as "hazardous substances", "hazardous material", or "toxic
substances" in (A) the Comprehensive Environmental Response, Compensation and
Liability Act of 1980, as amended by the Superfund Amendments and
Reauthorization Act of 1986 or as otherwise amended, 42 U.S.C. ss.9601, et seq.,
(B) the Hazardous Materials Transportation Act, 49 U.S.C. ss.1801 et seq. and
any amendments thereto, or (C) the Resource Conservation and Recovery Act, 42
U.S.C. ss.6901, et seq. and any amendments thereto; (11) those substances
defined as "hazardous wastes", "extremely hazardous wastes" or "restricted
hazardous wastes" in ss.ss.25115, 25117, and 25122.7 or listed pursuant to
ss.25140 of the California Health & Safety Code and any amendments thereto; (12)
those substances defined as "hazardous substances" in ss.25316 of the California
Health & Safety Code and any amendments thereto; (13) those substances defined
as "hazardous material", "hazardous wastes" or "hazardous substances" in
ss.ss.25501 and 25501.1 of the California Health & Safety Code and any
amendments thereto; (14) those substances defined as "hazardous substances"
under ss.25281 of the California Health & Safety Code and any amendments
thereto; (15) those substances causing "pollution" or "contamination" or
constituting "hazardous substances" within the meaning of (A) the Clean Water
Act, 33 U.S.C. ss.1251 et seq. and any amendments thereto, (B) the
Porter-Cologne Water Quality Control Act, ss.13050 of the California Water Code
and any amendments thereto, and (C) the Safe Drinking Water Act, 42 U.S.C.
ss.300f et seq.; (16) such chemicals as are identified on the list published
from time to time as provided in Chapter 6.6 of the California Health and Safety
Code, as amended, as causing cancer or reproductive toxicity; (17)
polychlorinated biphenyls (PCBs) set forth in the Federal Toxic Substance
Control Act, as amended, 15 U.S.C. ss.2601 et seq.; (18) "toxic air contaminant"
as defined in California Health and Safety Code ss.39655;(19) the wastes,
substances, materials, contaminants and pollutants identified pursuant to or set
forth in the Regulations adopted or judicial or administrative orders, decisions
or decrees promulgated pursuant to any of the foregoing laws; and (20) all
receptacles and containers for any and all materials referred to above. The
foregoing list of definitions and statutes is intended to be illustrative and
not exhaustive and such list shall be deemed to include all definitions, rules,
regulations and laws applicable to the subject matter of this paragraph as such
rules, laws, regulations and definitions may be amended, modified, or changed
from time to time.

     18.5.2. "Environmental Health and Safety Requirement" means any Regulation,
order, judgment or decree promulgated by any local, regional, state or federal
governmental agency, court, judicial or quasi-judicial body or legislative or
quasi-legislative body which relates to matters of the environment, health,
industrial hygiene or safety.

     18.6. Allocation of Responsibilities. ALL LIABILITIES ARISING FROM THE
HANDLING OF HAZARDOUS MATERIAL IN, ON, UNDER, AND/OR ABOUT THE PROPERTY OR ANY
ADJOINING PROPERTY BY TENANT AND ITS AGENTS, SHALL REMAIN TENANT'S SOLE
RESPONSIBILITY. NOTWITHSTANDING ANYTHING IN THIS LEASE, NO ACT BY LANDLORD OR
ITS AGENTS SHALL BE CONSTRUED AS LANDLORD'S ASSUMPTION OF ANY OBLIGATIONS,
DUTIES, LIABILITIES OR RESPONSIBILITIES PERTAINING TO TENANT'S COMPLIANCE WITH
ANY ENVIRONMENTAL, HEALTH OR SAFETY REQUIREMENT. NOTWITHSTANDING THE EXPIRATION
OR TERMINATION OF THIS LEASE AND NOTWITHSTANDING ANY OTHER PROVISION OF THIS
LEASE, TENANT SHALL RETAIN ALL LIABILITY AND RESPONSIBILITY OF COMPLIANCE WITH
REGULATIONS CONCERNING TENANT AND ITS AGENT'S HANDLING OF HAZARDOUS MATERIAL
EVEN IF SUCH HAZARDOUS MATERIAL ORIGINATE FROM THE PROPERTY. TENANT SHALL
INDEMNIFY, DEFEND AND HOLD LANDLORD AND ITS AGENTS HARMLESS FROM ALL SUCH COSTS
AND EXPENSES AS MAY BE ASSOCIATED WITH SUCH COMPLIANCE.

     18.7. Inspections. Tenant warrants that Tenant will cooperate and not
interfere with completion of any and all governmental inspections of the
Property as required by applicable

                                       16
<PAGE>

Regulation. Tenant shall provide to Landlord a copy of the reports for each such
inspection within 15 Days of Tenant's receipt of such reports.

     18.8. Survival. Tenant's and Landlord's covenants, agreements and
indemnities set forth in this Section 18 shall survive the expiration or
Termination of this Lease and shall not be affected by any investigation, or
information obtained as a result of any investigation, by or on behalf of
Landlord or any prospective Tenant.

     18.9. Storage Tanks. Tenant shall not install any storage tank (above or
below the ground) on the Property without Landlord's prior written consent,
which consent may be conditioned upon further requirements imposed by Landlord
with respect to compliance by Tenant with any applicable Regulations and safety
measures or financial responsibility requirements.

     18.10. Landlord's Obligations.

     18.10.1. Restrictions on Hazardous Material. Landlord shall not cause or
permit Hazardous Material to be Handled in, on, about or under the Property
except in compliance with all Environmental Health and Safety Requirements
regulating such Hazardous Material.

     18.10.2. Compliance With Regulations. If any Hazardous Material is Handled
in, on or about the Property by Landlord, Landlord shall bear all financial and
other responsibility for ensuring that such material is Handled in compliance
with all Environmental, Health and Safety Requirements regulating such Hazardous
Material and with the highest standards prevailing in the industry for the use,
keeping and storage of such Hazardous Material.

     18.10.3. Restoration. If, as a result of Landlord's Handling Hazardous
Material upon the Property or any adjoining property, prior to or during the
Term, any contamination of the Property or the surrounding environment occurs;
Landlord shall promptly take all actions at its sole cost and expense as are
necessary to return the Property and/or the surrounding environment to the
condition existing prior to such contamination.

     18.10.4. Duty to Notify Tenant. Landlord shall notify Tenant in writing on
becoming aware of: (1) any enforcement, cleanup, remediation or other action
threatened, instituted or completed by any governmental or regulatory agency or
private person with respect to the Property relating to Hazardous Material; (2)
any claim threatened or made against Landlord with respect to the Property,
Tenant or the Property for personal injury, compensation or any other matter
relating to Hazardous Material; and (3) any reports made by or to any
governmental or regulatory agency respecting the Property, any complaints,
notices or asserted violations in connection therewith. Landlord shall also
supply to Tenant copies of all claims, reports, complaints, notices, warnings,
asserted violations or other documents relating to the foregoing.

     18.10.5. Landlord's Indemnity of Tenant. If the presence of Hazardous
Material on the Property or any adjoining property, as a result of the acts of
Landlord, other Tenants or third parties invited or allowed upon the Property by
Landlord (other than Tenant's Agents) results in contamination of the Property,
or if any contamination of the Property exists as of the Commencement Date then
Landlord shall indemnify, defend and hold Tenant, its officers, Agents and
representatives harmless from and against any and all claims, damages,
penalties, fines, costs, liabilities and losses, damages for the loss or
restriction on use of rental or usable space or of any other amenity of the
Property and sums paid in settlement of claims, attorneys' fees, consultants'
fees and experts' fees) which arise during or after the Term as a result of such
contamination.

19.  MISCELLANEOUS PROVISIONS.

     19.1. Waiver. No waiver of any breach of a covenant or condition of this
Lease shall be construed as a waiver of any other breach or as a consent to any
further or succeeding breach of the same covenant or condition. Landlord's
acceptance of rent after Tenant's breach shall not be deemed a waiver of any
preceding breach by Tenant of any term, covenant or condition of this Lease,
other than Tenant's failure to pay the rent so accepted, regardless of
Landlord's knowledge of such preceding breach at the time Landlord accepts the
rent.

     19.2. Successors and Assigns. Except as otherwise provided, this Lease
shall bind inure to the benefit of the heirs, personal representatives,
successors and assigns of the parties.

                                       17
<PAGE>
     19.3. Notices. All notices, requests, demands and other communications
required or permitted to be given hereunder shall be in writing and either
personally delivered or sent by certified mail, return receipt requested,
postage prepaid, properly addressed to the other party at the address set forth
next to its signature below, or at such other address as may, from time to time,
be designated in writing by one party to the other. Notice shall be deemed given
when personally delivered or on the date indicated on the post office's
certified mail receipt of delivery.

     19.4. Partial Invalidity. If any provision of this Lease is determined to
be invalid or inoperative, the other provisions of this Lease shall not be
affected.

     19.5. Number and Gender. All terms of this Lease shall be construed to mean
either the singular or the plural, masculine, feminine or neuter, as the
situation may demand.

     19.6. Descriptive Headings. The headings used herein and in documents
annexed as schedules, lists or exhibits are descriptive only for the convenience
of identifying provisions, and not determinative of the meaning or effect of any
such provision.

     19.7. Time. In all matters, time is of the essence in the performance of
all obligations under this Lease. The provisions of this paragraph are material
and not a mere recital.

     19.8. Entire Agreement. This Lease and the documents annexed hereto as
schedules, lists or exhibits, constitutes the entire agreement and understanding
between the parties respecting the subject matters addressed. This Lease
supersedes and replaces all prior agreements and understandings, (oral or
written), between the parties with respect to the hiring of the Premises and all
related matters. The provisions of this Lease may be waived, altered, amended or
repealed only upon Landlord's and Tenant's written consent.

     19.9. Memorandum of Lease. If Landlord requests a recorded memorandum of
this Lease, all parties shall execute and acknowledge such memorandum
identifying: the Premises, the parties, the Commencement Date and the
Termination. The memorandum may be recorded in the county where the Premises are
located. No other memorandum of the Lease shall be recorded.

     19.10. Applicable Law. This Lease shall be construed and interpreted in
accordance with the laws of the State of California.

     19.11. Authority. Each individual executing this Lease on behalf of a
corporation represents and warrants that he is duly authorized to execute and
deliver this Lease on behalf of the corporation in accordance with a duly
adopted resolution of the Board of Directors of the corporation, and that this
Lease is binding upon said corporation in accordance with its Terms. Each
individual executing this Lease on behalf of a partnership represents and
warrants that he is duly authorized to execute and deliver this Lease on behalf
of the partnership and that this Lease is binding upon said partnership in
accordance with its terms.

     19.12. Litigation Expense. If any party brings an action or arbitration
proceeding against any other party hereto by reason of the breach of any
covenant, warranty, representation or condition hereof, or otherwise arising out
of this Lease, whether for declaratory or other relief, the prevailing party
shall be entitled to costs of suit and attorneys' fees, which shall be payable
whether or not such action is prosecuted to judgment.

     19.13. Subordination of Leasehold. This Lease is and shall be, at all
times, subject and subordinate to the lien of any mortgage or other encumbrances
which Landlord may create against the Property, including all renewals,
replacements and extensions. Tenant shall execute all written instruments which
may be required by Landlord to subordinate Tenant's rights to the lien of such
mortgage which obligation by Tenant is conditioned upon the holder of such lien
providing to Tenant a written nondisturbance agreement providing, in essence,
that as long as Tenant is not in default under the provisions of this Lease, the
lender will, in the event of a foreclosure, allow Tenant to remain in possession
of the Premises for the duration of the unexpired Term.

     19.14. Estoppel Certificate. Within 15 Days following Landlord's request,
Tenant shall complete, execute and deliver to Landlord an estoppel certificate
in a form provided by Landlord, setting forth the information requested therein,
including, but not limited to, (a) certification that this Lease is unmodified
and in full force and effect (or if modified, stating the nature of such
modification and certifying that this Lease as so modified is in full force and
effect) and the date to which the rental and other charges are paid in advance,
if any, (b) acknowledgment that there are not, to Tenant's knowledge, any
uncured defaults on the part of Landlord hereunder,

                                       18
<PAGE>
or specifying such defaults, if any are claimed, and (c) setting forth the
Commencement Date and expiration of the Term. Tenant's failure to deliver the
certificate within said 15 Days shall be deemed, for all purposes, to be a
certification that Landlord is not in default under the Lease, and that the
Terms of the Lease are in force and have not been modified in any way. Any
prospective purchaser, lender or assignee of any lender against the Property may
rely upon such certification.

     19.15. Attornment. In the event of any sale of the Property or if
proceedings are brought for the foreclosure of, or in the event of exercise of
the power of sale under, any mortgage, installment land contract or deed of
trust covering the Property, Tenant shall attorn to the mortgagee or the
purchaser upon any such foreclosure or sale and recognize such mortgagee or
purchaser as Landlord under this Lease, which obligation by Tenant is
conditioned upon Tenant receiving a written nondisturbance agreement providing,
in essence, that as long as Tenant is not in default under the provisions of
this Lease, Tenant will be allowed to remain in possession of the Premises for
the unexpired duration of the Term.

     19.16. Compliance with Lender's Requests. Tenant shall consent to
amendments to this Lease from time to time as may be requested by any current or
future mortgagee or holder of other encumbrance which Landlord may create
against the Property, provided that such amendments do not materially affect
Tenant's rights or obligations under this Lease. Tenant agrees to timely supply,
financial information reasonably requested by Landlord for lenders analysis of
Tenant's financial condition as a condition of any encumbrance of the Property.

     19.17. Rules and Regulations. Tenant shall faithfully observe and comply
with all rules and regulations and all modifications thereof and additions
thereto from time to time promulgated by Landlord. Landlord shall not be
responsible for any loss, injury or damage resulting from the nonperformance by
any other tenant or occupant of said rules and regulations.

     19.18. Deleted.

     19.19. Submission of Lease. Submission of this document for Tenant's
examination or signature does not constitute a reservation of or option for
lease, nor does it create any obligation on Landlord's part until execution and
delivery by both Landlord and Tenant.

     19.20. Arbitration of Disputes. IF A CONTROVERSY, CLAIM OR DISPUTE
(COLLECTIVELY "DISPUTE") BETWEEN THE PARTIES ARISES OUT OF THIS LEASE, THE
DISPUTE SHALL BE SUBMITTED TO BINDING ARBITRATION TO BE CONDUCTED UNDER THE
COMMERCIAL ARBITRATION RULES OF THE AMERICAN ARBITRATION ASSOCIATION; JUDGMENT
ON THE ARBITRATOR'S AWARD MAY BE ENTERED IN ANY COURT OF COMPETENT JURISDICTION.
CALIFORNIA CODE OF CIVIL PROCEDURE ss.1283.05 SHALL APPLY TO SUCH ARBITRATION.

     NOTICE: BY INITIALLING IN THE SPACE BELOW YOU ARE AGREEING TO HAVE ANY
DISPUTE ARISING OUT OF THE MATTERS INCLUDED IN THE "ARBITRATION OF DISPUTES"
PROVISIONS DECIDED BY NEUTRAL ARBITRATION AS PROVIDED BY CALIFORNIA LAW AND YOU
ARE GIVING UP ANY RIGHTS YOU MIGHT POSSESS TO HAVE THE DISPUTE LITIGATED IN A
COURT OR JURY TRIAL. BY INITIALLING IN THE SPACE BELOW YOU ARE GIVING UP YOUR
JUDICIAL RIGHTS TO DISCOVERY AND APPEAL UNLESS THOSE RIGHTS ARE SPECIFICALLY
INCLUDED IN THE "ARBITRATION OF DISPUTES" PROVISION. IF YOU REFUSE TO SUBMIT TO
ARBITRATION AFTER AGREEING TO THIS PROVISION YOU MAY BE COMPELLED TO ARBITRATE
UNDER THE AUTHORITY OF THE CALIFORNIA CODE OF CIVIL PROCEDURE. YOUR AGREEMENT TO
THIS ARBITRATION PROVISION IS VOLUNTARY.

WE HAVE READ AND UNDERSTAND THE FOREGOING AND AGREE TO SUBMIT DISPUTES ARISING
OUT OF THE MATTERS INCLUDED IN THE "ARBITRATION OF DISPUTES" PROVISION TO
NEUTRAL ARBITRATION.

/s/RR    /s/CLD
Initial  Initial

                                       19
<PAGE>
     19.21. Venue. Any action or arbitration arising out of or brought to
enforce or interpret the provisions of this Lease shall be venued in Alameda
County, California.

     19.22. Representation by Counsel. This Lease reflects negotiations
previously entered into by the parties acting as principals for their own
accounts. This Lease has been drafted by Graves, Allen, Cornelius & Celestre,
Attorneys ("GACC"), acting solely and exclusively as attorneys for Landlord.
GACC has not represented Tenant in any manner with respect to the transaction.
GACC has not provided any legal or tax advice whatsoever to Tenant in
conjunction with any aspect of this transaction. Tenant understands that this
Lease significantly affects its legal rights and acknowledges that it has had
the opportunity to obtain legal and tax counsel and has obtained such counsel
and advice as it deems necessary. Tenant expressly waives any objection to GACC
representing Landlord in any Dispute concerning or arising out of this Lease.

     19.23. Brokerage. Tenant represents and warrants to Landlord that Tenant
has not contacted or been contacted by any real estate licensee with respect to
the negotiation of this Lease or the availability of the Premises for lease.

     19.24. Parking. Tenant shall have nonexclusive rights to parking as
designated in a plan to be developed by Landlord and reasonably approved by
Tenant. Parking areas shall be on the Property. Landlord will provide a minimum
of three spaces parking spaces per thousand usable square feet of Tenant's
Premises (defined as that portion of the Premises allocated to Tenant's
exclusive use and exclusive of any Common Area allocated to Tenant).

     19.25. Use of Amenities. Tenant shall have a non-exclusive right to use of
all Common Area amenities for the Property on the same basis as all other
tenants of the Property.

     19.26. Signs. Tenant shall place no signs upon the Property. Landlord may
provide, as an expense of the Property, a monument sign and/or directory sign,
which may include Tenant's sign. The design of any such sign for Tenant shall
conform to the style and quality of signs used for other tenants of the
Property.

     19.27. Cooperation. Tenant will not interfere with any actions by Landlord
made in furtherance of any Regulation affecting the Property. Tenant shall
comply with all reasonable procedures and regulations promulgated by Landlord
from time to time in connection with the matters covered by such Regulations.
Nothing in this paragraph shall impose upon Landlord any duty to establish any
procedures or regulations or to supervise, in any way, Tenant's activities upon
the Premises or the Property for any purpose including, without limitation, the
regulation of the storage, use and handling of Hazardous Material.

     19.28. First Right of Refusal. If, at any time during the Term, any portion
of the Building currently occupied by Natural Language, Inc. (the "NLI Space")
shall be vacated by Natural Language, Inc., Landlord shall offer such space to
Tenant prior to making it available to any other party. Landlord shall advise
Tenant in writing of the availability of the NLI Space (the "Availability
Notice") and Tenant shall have 10 Days following delivery of the Availability
Notice within which to elect, in writing delivered to Landlord, to rent the NLI
Space. Tenant's failure to timely deliver to Landlord Tenant's written election
(the "Election Notice") to rent the NLI Space shall be deemed Tenant's
irrevocable waiver of the First Right of Refusal created by this paragraph. As
used in this paragraph, "NLI Space" includes all and any portion of the space
currently occupied by Natural Language, Inc.). If Tenant elects to exercise the
First Right of Refusal created by this paragraph, Tenant shall assume occupancy
of the NLI Space forthwith upon Natural Language, Inc. vacating the NLI Space.
Tenant's timely delivery of its Election Notice to Landlord shall act as an
amendment to this Lease which amendment modifies the terms of this Lease by
incorporation of the NLI Space and adjustment of the square footage of the
Premises to reflect the additional space. Pursuant to the provisions of this
Lease, such modification of the square footage of the Premises will also cause
the Lease to be amended to reflect the additional square footage in the
calculation of the Pro Rata Share and the Base Monthly Rent. Tenant shall occupy
the NLI Space incorporated through the Election Notice under the same terms and
conditions as are in force under the provisions of this Lease for the remainder
of the Term. Landlord shall have no obligation to make any alterations or
modifications or improvements to the NLI Space.

                                       20
<PAGE>
20.      TERMINATION OF OLD LEASE.

Landlord and Tenant hereby agree that the Old Lease shall be terminated and
cancelled effective December 31, 1991 which termination and cancellation is
conditioned upon the execution of this Lease by Landlord and Tenant. Upon the
cancellation of the Old Lease, Landlord and Tenant shall each be released from
any and all obligations one to the other under the provisions of the Old Lease
and this Lease shall be the sole document setting forth the obligations of
Landlord and Tenant to each other with respect to the Property and Tenant's
occupancy of the Premises.

IN WITNESS WHEREOF, the parties have executed this Lease on the date first
written above.

LANDLORD:                                   TENANT:

By /s/ Randy K. Robbins                     By /s/ Clarence L. Dellio
- ----------------------------                ------------------------------
General Partner                             Authorized Officer

Address for Notices:                        Address for Notices:

1120 Nye Street                             2910 Seventh Street
Suite 400                                   Suite 100
San Rafael, California 94901                Berkeley, California 94710

                                       21




                         Standard Industrial Lease - Net
                           REFERENCE DATE, June 22, 92
                            REVISED DATE, July 28, 92
                   AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION
                                   AIR (LOGO)

1. Parties. This Lease, dated, for reference purposes only, June 22, 1992, is
made by and between Richard B. Gomez, Josephine L. Gomez, TTEE U/A/D, 10, 31-90
FBO Gomez Family Trust(herein called "Lessor") and XOMA Corp.
2910 Seventh St, Berkeley, Ca. 94710 (herein called "Lessee").

2. Premises. Lessor hereby leases to Lessee and Lessee leases from Lessor for
the term, at the rental, and upon all of the conditions set forth herein, that
certain real property situated in the County of Los Angeles State of Ca.,
commonly known as 1701 Colorado and 1553 - 17th St. Santa Monica, Ca. 90404 and
described as two separate adjacent Brick buildings consisting of approximately
7500 sq. ft. and 2500 sq. ft. with a total of approximately 18 cars, of parking
area. Said real property including the land and all improvements therein, is
herein called "the Premises".

3.  Term.
         3.1 Term. The term of this Lease shall be for Three years (36) months
commencing on January 1, 1993 and ending on December 31, 1995 unless sooner
terminated pursuant to any provision hereof. See ADDENDUM #2, Option Period: #50

         3.2 Delay in Possession. Notwithstanding said commencement date, if for
any reason Lessor cannot deliver possession of the Premises to Lessee on said
date, Lessor shall not be subject to any liability therefor, nor shall such
failure affect the validity of this Lease or the obligations of Lessee hereunder
or extend the term hereof, but in such case, Lessee shall not be obligated to
pay rent until possession of the Premises is tendered to Lessee; provided,
however, that if Lessor shall not have delivered possession of the Premises
within sixty (60) days from said commencement date, Lessee may, at Lessee's
option, by notice in writing to Lessor within ten (10) days thereafter, cancel
this Lease, in which event the parties shall be discharged from all obligations
hereunder; provided further, however, that if such written notice of Lessee is
not received by Lessor within said ten (10) day period, Lessee's right to cancel
this Lease hereunder shall terminate and be of no further force or effect.

         3.3 Early Possession. If Lessee occupies the Premises prior to said
commencement date, such occupancy shall be subject to all provisions hereof,
such occupancy shall not advance the termination date, and Lessee shall pay rent
for such period at the initial monthly rates set forth below.

4. Rent. See additional rent schedule. Lessee shall pay Lessor upon the
execution hereof $11,500.00 as rent for Feb, 1993. See additional rent schedule
ADDENDUM paragraph #48. Rent for any period during the term hereof which is for
less than one month shall be a pro rata portion of the monthly installment. Rent
shall be payable in lawful money of the United States to Lessor at the address
stated herein or to such other persons or at such other places as Lessor may
designate in writing.

5. Security Deposit. Lessee shall deposit with Lessor upon execution hereof (See
Paragraph #49) as security for Lessee's faithful performance of Lessee's
obligations hereunder. If Lessee fails to pay rent or other charges due
hereunder, or otherwise defaults with respect to any provision of this Lease,
Lessor may use, apply or retain all or any portion of said deposit for the
payment of any rent or other charge in default or for the payment of any other
sum to which Lessor may become obligated by reason of Lessee's default, or to
compensate Lessor for any loss or damage which Lessor may suffer thereby. If
Lessor so uses or applies all or any portion of said deposit, Lessee shall
within ten (10) days after written demand therefor deposit cash with Lessor in
an amount sufficient to restore said deposit to the full amount hereinabove
stated and Lessee's failure to do so shall be a material breach of this Lease.
If the monthly rent shall, from time to time, increase during the term of this
Lease, Lessee shall thereupon deposit with Lessor additional security deposit so
that the amount of security deposit held by Lessor shall at all times bear the
same proportion to current rent as the original security deposit bears the
original monthly rent set forth in paragraph 4 hereof. Lessor shall not be
required to keep said deposit separate from its general accounts. If Lessee
performs all of Lessee's obligations hereunder, said deposit, or so much thereof
as has not theretofore been applied by Lessor, shall be returned, without
payment of interest or other increment for its use, to Lessee (or, at Lessor's
option, to that last assignee, if any, of Lessee's interest hereunder) at the
expiration of the term hereof, and after Lessee has vacated the Premises. No
trust relationship is created herein between Lessor and Lessee with respect to
said Security Deposit.

6.  Use.
         6.1 Use. The Premises shall be used and occupied only for research,
light manufacturing, laboratories and offices and all other lawful uses or any
other use which is reasonably comparable and for no other purpose.
         6.2  Compliance with Law.
                  (a) Lessor warrants to Lessee that the Premises, in its state
existing on the date that the Lease term commences, but without regard to the
use for which Lessee will use the Premises, does not violate any covenants or
restrictions of record, or any applicable building code, regulation or ordinance
in effect on such Lease term commencement date. In the event it is determined
that this warranty has been violated, then it shall be the obligation of the
Lessor, after written notice from Lessee, to promptly, at Lessor's sole cost and
expense, rectify any such violation. In the event Lessee does not give to Lessor
written notice of the violation of this warranty within six months from the date
that the Lease term commences, the correction of same shall be the obligation of
the Lessee at Lessee's sole cost. The warranty contained in this paragraph 6.2
(a) shall be of no force or effect if, prior to the date of this Lease, Lessee
was the owner or occupant of the Premises, and, in such event, Lessee shall
correct any such violation at Lessee's sole cost.
                  (b) Except as provided in paragraph 6.2(a), Lessee shall, at
Lessee's expense, comply promptly with all applicable statutes, ordinances,
rules, regulations, orders, covenants and restrictions of record, and
requirements in effect during the term or any part of the term hereof,
regulating the use by Lessee of the Premises. Lessee shall not use nor permit
the use of the Premises in any manner that will tend to create waste or a
nuisance or, if there shall be more than one tenant in the building containing
the Premises, shall tend to disturb such other tenants.
         6.3  Condition of Premises
                  (a) Lessor shall deliver the Premises to Lessee clean and free
of debris on Lease commencement date (unless Lessee is already in possession)
and Lessor further warrants to Lessee that the plumbing, lighting, air
conditioning, heating, and loading doors in the Premises shall be in good
operating condition on the Lease commencement date. In the event that it is
determined that this warranty has been violated, then it shall be the obligation
of Lessor, after receipt of written notice from Lessee setting forth with
specificity the nature of the violation, to promptly, at Lessor's sole cost,
rectify such violation. Lessee's failure to give such written notice to Lessor
within thirty (30) days after the Lease commencement date shall cause the
conclusive presumption that Lessor has complied with all of Lessor's obligations
hereunder. The warranty contained in this paragraph 6.3(a) shall be of no force
or effect if prior to the date of this Lease, Lessee was the owner or occupant
of the Premises.
                  (b) Except as otherwise provided in this Lease, Lessee hereby
accepts the Premises in their condition existing as of the Lease commencement
date or the date that Lessee takes possession of the Premises, whichever is
earlier, subject to all applicable zoning, municipal, county and state laws,
ordinances and regulations governing and regulating the use of the Premises, and
any covenants or restrictions of record, and accepts this Lease subject thereto
and to all matters disclosed thereby and by any exhibits attached hereto. Lessee
acknowledges that neither Lessor nor Lessor's agent has made any representation
or warranty as to the present or future suitability of the Premises for the
conduct of Lessee's business.

7.  Maintenance, Repairs and Alterations.
         7.1 Lessee's Obligations. Lessee shall keep in good order, condition
and repair the Premises and every part thereof, structural and non structural,
(whether or not such portion of the Premises requiring repair, or the means of
repairing the same are reasonably or readily accessible to Lessee, and whether
or not the need for such repairs occurs as a result of Lessee's use, any prior
use, the elements or the age of such portion of the Premises) including, without
limiting the generality of the foregoing, all plumbing, heating, air
conditioning, (Lessee shall procure and maintain, at Lessee's expense, an air
conditioning system maintenance contract) ventilating, electrical, lighting
facilities and equipment within the Premises, fixtures, walls (interior and
exterior), ceilings, roofs (interior and exterior), floors, windows, doors,
plate glass and skylights located within the Premises, and all landscaping,
driveways, parking lots, fences and signs located on the Premises and sidewalks
and parkways adjacent to the Premises.
         7.2 Surrender. On the last day of the term hereof, or on any sooner
termination, Lessee shall surrender the Premises to Lessor in the same condition
as when received, ordinary wear and tear excepted, clean and free of debris.
Lessee shall repair any damage to the Premises occasioned

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by the installation or removal of Lessee's trade fixtures, furnishings and
equipment. Notwithstanding anything to the contrary otherwise stated in this
Lease, Lessee shall leave the air lines, power panels, electrical distribution
systems, lighting fixtures, space heaters, air conditioning, plumbing and
fencing on the premises in good operating condition.
         7.3 Lessor's Rights. If Lessee fails to perform Lessee's obligations
under this Paragraph 7, or under any other paragraph of this Lease, Lessor may
at its option (but shall not be required to) enter upon the Premises after ten
(10) days' prior written notice to Lessee (except in the case of an emergency,
in which case no notice shall be required), perform such obligations on Lessee's
behalf and put the same in good order, condition and repair, and the cost
thereof together with interest thereon at the maximum rate then allowable by law
shall become due and payable as additional rental to Lessor together with
Lessee's next rental installment.
         7.4 Lessor's Obligations. Except for the obligations of Lessor under
Paragraph 6.2(a) and 6.3(a) (relating to Lessor's warranty), Paragraph 9
(relating to destruction of the Premises) and under Paragraph 14 (relating to
condemnation of the Premises), it is intended by the parties hereto that Lessor
have no obligation, in any manner whatsoever, to repair and maintain the
Premises nor the building located thereon nor the equipment therein, whether
structural or non structural, all of which obligations are intended to be that
of the Lessee under Paragraph 7.1 hereof. Lessee expressly waives the benefit of
any statute now or hereinafter in effect which would otherwise afford Lessee the
right to make repairs at Lessor's expense or to terminate this Lease because of
Lessor's failure to keep the premises in good order, condition and repair.
         7.5  Alterations and Additions
                  (a) Lessee shall not, without Lessor's prior written consent
make any alterations, improvements, additions, or Utility installations in, on
or about the Premises, except for nonstructural alterations not exceeding
$20,000.00 in cumulative costs during the term of this Lease. In any event,
whether or not in excess of $20,000.00 in cumulative cost, Lessee shall make no
change or alteration to the exterior of the Premises nor the exterior of the
building(s) on the Premises without Lessor's prior written consent. As used in
this Paragraph 7.5 the term "Utility Installation" shall mean carpeting, window
coverings, air lines, power panels, electrical distribution systems, lighting
fixtures, space heaters, air conditioning, plumbing, and fencing. Lessor may
require that Lessee remove any or all of said alterations, improvements,
additions or Utility Installations at the expiration of the term, and restore
the Premises to their prior condition. Lessor may require Lessee to provide
Lessor, at Lessee's sole cost and expense, a lien and completion bond in an
amount equal to one and one-half times the estimated cost of such improvements,
to insure Lessor against any liability for mechanic's and materialmen's liens
and to insure completion of the work. Should Lessee make any alterations,
improvements, additions or Utility Installations without the prior approval of
Lessor, Lessor may require that Lessee remove any or all of the same.
         (b) Any alterations, improvements, additions or Utility Installations
in, or about the Premises that Lessee shall desire to make and which requires
the consent of the Lessor shall be presented to Lessor in written form, with
proposed detailed plans. If Lessor shall give its consent, the consent shall be
deemed conditioned upon Lessee acquiring a permit to do so from appropriate
governmental agencies, the furnishing of a copy thereof to Lessor prior to the
commencement of the work and the compliance by Lessee of all conditions of said
permit in a prompt and expeditious manner.
         (c) Lessee shall pay, when due, all claims for labor or materials
furnished or alleged to have been furnished to or for Lessee at or for use in
the Premises, which claims are or may be secured by any mechanics' or
materialmen's lien against the Premises or any interest therein. Lessee shall
give Lessor not less than ten (10) days' notice prior to the commencement of any
work in the Premises, and Lessor shall have the right to post notices of
non-responsibility in or on the Premises as provided by law. If Lessee shall, in
good faith, contest the validity of any such lien, claim or demand, then Lessee
shall, at its sole expense defend itself and Lessor against the same and shall
pay and satisfy any such adverse judgment that may be rendered thereon before
the enforcement thereof against the Lessor or the Premises, upon the condition
that if Lessor shall require, Lessee shall furnish to Lessor a surety bond
satisfactory to Lessor in an amount equal to such contested lien claim or demand
indemnifying Lessor against liability for the same and holding the Premises free
from the effect of such lien or claim. In addition, Lessor may require Lessee to
pay Lessor's attorneys fees and costs in participating in such action if Lessor
shall decide it is to its best interest to do so.
         (d) Unless Lessor requires their removal, as set forth in Paragraph
7.5(a), all alterations, improvements, additions and Utility Installations
(whether or not such Utility Installations constitute trade fixtures of Lessee),
which may be made on the Premises, shall become the property of Lessor and
remain upon and be surrendered with the Premises at the expiration of the term.
Notwithstanding the provisions of this Paragraph 7.5(d), Lessee's machinery and
equipment, other than that which is affixed to the Premises so that it cannot be
removed without material damage to the Premises, shall remain the property of
Lessee and may be removed by Lessee subject to the provisions of Paragraph 7.2,
or can be removed and building returned to its initial state.

8.  Insurance Indemnity.
         8.1 Insuring Party. As used in this Paragraph 8, the term "Insuring
party" shall mean the party who has the obligation to obtain the Property
Insurance required hereunder. The insuring party shall be designated in
Paragraph 46 hereof. In the event Lessor is the insuring party, Lessor shall
also maintain the liability insurance described in paragraph 8.2 hereof, in
addition to, and not in lieu of, the insurance required to be maintained by
Lessee under said paragraph 8.2, but Lessor shall not be required to name Lessee
as an additional insured on such policy. Whether the insuring party is the
Lessor or the Lessee, Lessee shall, as additional rent for the Premises, pay the
cost of all insurance required hereunder, except for that portion of the cost
attributable to Lessor's liability insurance coverage in excess of $1,000,000
per occurrence. If Lessor is the insuring party Lessee shall, within ten (10)
days following demand by Lessor, reimburse Lessor for the cost of the insurance
so obtained.
         8.2 Liability Insurance. Lessee shall, at Lessee's expense obtain and
keep in force during the term of this Lease a policy of Combined Single Limit,
Bodily Injury and Property Damage insurance insuring Lessor and Lessee against
any liability arising out of the ownership, use, occupancy or maintenance of the
Premises and all areas appurtenant thereto. Such insurance shall be a combined
single limit policy in an amount not less than $500,000 per occurrence. The
policy shall insure performance by Lessee of the indemnity provisions of this
Paragraph 8. The limits of said insurance shall not, however, limit the
liability of Lessee hereunder.
         8.3  Property Insurance.
                  (a) The insuring party shall obtain and keep in force during
the term of this Lease a policy or policies of insurance covering loss or damage
to the Premises, in the amount of the full replacement value thereof, as the
same may exist from time to time, which replacement value is now $999,000.00,
but in no event less than the total amount required by lenders having liens on
the Premises, against all perils included within the classification of fire,
extended coverage, vandalism, malicious mischief, flood (in the event same is
required by a lender having a lien on the Premises), and special extended perils
("all risk" as such term is used in the insurance industry) Excluding in any
event earthquake Insurance, said insurance shall provide for payment of loss
thereunder to Lessor or to the holders of mortgages or deeds of trust on the
Premises. The insuring party shall, in addition, obtain and keep in force during
the term of this Lease a policy of rental value insurance covering a period of
one year, with loss payable to Lessor, which insurance shall also cover all real
estate taxes and insurance costs for said period. A stipulated value or agreed
amount endorsement deleting the coinsurance provision of the policy shall be
procured with said insurance. If the insuring party shall fail to procure and
maintain said insurance the other party may, but shall not be required to,
procure and maintain the same, but at the expense of Lessee. If such insurance
coverage has a deductible clause, the deductible amount shall not exceed
$5,000.00 per occurrence, and Lessee shall be liable for such deductible amount.
                  (b) If the Premises are part of a larger building, or if the
Premises are part of a group of buildings owned by Lessor which are adjacent to
the Premises, then Lessee shall pay for any increase in the property insurance
of such other building or buildings if said increase is caused by Lessee's acts,
omissions, use or occupancy of the Premises.
                  (c) If the Lessor is the insuring party the Lessor will not
insure Lessee's fixtures, equipment or tenant improvements unless the tenant
improvements have become a part of the Premises under paragraph 7, hereof. But
if Lessee is the insuring party the Lessee shall insure its fixtures, equipment
and tenant improvements.

         8.4 Insurance Policies. Insurance required hereunder shall be in
companies holding a "General Policyholders Rating" of at least B plus, or such
other rating as may be required by a lender having a lien on the Premises, as
set forth in the most current issue of "Best's Insurance Guide". The insuring
party shall deliver to the other party copies of policies of such insurance or
certificates evidencing the existence and amounts of such insurance with loss
payable clauses as required by this paragraph 8. No such policy shall be
cancellable or subject to reduction of coverage or other modification except
after thirty (30) days' prior written notice to Lessor. If Lessee is the
insuring party Lessee shall, at least thirty (30) days prior to the expiration
of such policies, furnish Lessor with renewals or "binders" thereof, or Lessor
may order such insurance and charge the cost thereof to Lessee, which amount
shall be payable by Lessee upon demand. Lessee shall not do or permit to be done
anything which shall invalidate the insurance policies referred to in Paragraph
8.3. If Lessee does or permits to be done anything which shall increase the cost
of the insurance policies referred to in Paragraph 8.3, then Lessee shall
forthwith upon Lessor's demand reimburse Lessor for any additional premiums
attributable to any act or omission or operation of Lessee causing such increase
in the cost of insurance. If Lessor is the insuring party, and if the insurance
policies maintained hereunder cover other improvements in addition to the
Premises, Lessor shall deliver to Lessee a written statement setting forth the
amount of any such insurance cost increase and showing in reasonable detail the
manner in which it has been computed.

         8.5 Waiver of Subrogation. Lessee and Lessor each hereby release and
relieve the other, and waive their entire right of recovery against the other
for loss or damage arising out of or incident to the perils insured against
under paragraph 8.3, which perils occur in, on or about the Premises, whether
due to the negligence of Lessor or Lessee or their agents, employees,
contractors and/or invitees. Lessee and Lessor shall, upon obtaining the
policies of insurance required hereunder, give notice to the insurance carrier
or carriers that the foregoing mutual waiver of subrogation is contained in this
Lease.

         8.6 Indemnity. Lessee shall indemnify and hold harmless Lessor from and
against any and all claims arising from Lessee's use of the Premises, or from
the conduct of Lessee's business or from any activity, work or things done,
permitted or suffered by Lessee in or about the Premises or elsewhere and shall
further indemnify and hold harmless Lessor from and against any and all claims
arising from any breach or default in the performance of any obligation on
Lessee's part of be performed under the terms of this Lease, or arising from any
negligence of the Lessee, or any of Lessee's agents, contractors, or employees,
and from and against all costs, attorney's fees, expenses and liabilities
incurred in the defense of any such claim or any action or proceeding brought
thereon; and in case any action or proceeding be brought against Lessor by
reason of any such claim, Lessee upon notice from Lessor shall defend the same
at Lessee's expense by counsel satisfactory to Lessor.

         8.7 Exemption of Lessor from Liability. Lessee hereby agrees that
Lessor shall not be liable for injury to Lessee's business or any loss of income
therefrom or for damage to the goods, wares, merchandise or other property of
Lessee, Lessee's employees, invitees, customers, or any other person in or about
the Premises, nor shall Lessor be liable for injury to the person of Lessee,
Lessee's employees, agents or contractors whether such damage or injury is
caused by or results from fire, steam, electricity, gas, water or rain, or from
the breakage, leakage, obstruction or other defects of pipes, sprinklers, wires,
appliances, plumbing, air conditioning or lighting fixtures, or from any other
cause, except for Lessor's negligence or breach if its warranties, whether the
said damage or injury results from conditions arising upon the Premises or upon
other portions of the building of which the Premises are a part, or from other
sources or places and regardless of whether the cause of such damage or injury
or the means of repairing the same is inaccessible to Lessee. Lessor shall not
be liable for any damages arising from any act or neglect of any other tenant,
if any, of the building in which the Premises are located.

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9.  Damage or Destruction.

         9.1 Definitions.

                  (a) "Premises Partial Damage" shall herein mean damage or
destruction to the Premises to the extent that the cost of repair is less than
50% of the then replacement cost of the Premises. "Premises Building Partial
Damage" shall herein mean damage or destruction to the building of which the
Premises are a part to the extent that the cost of repair is less than 50% of
the then replacement cost of such building as a whole.

                  (b) "Premises Total Destruction" shall herein mean damage or
destruction to the Premises to the extent that the cost of repair is 50% or more
of the then replacement cost of the Premises. "Premises Building Total
Destruction" shall herein mean damage or destruction to the building of which
the Premises are a part to the extent that the cost of repair is 50% or more of
the then replacement cost of such building as a whole.

                  (c) "Insured Loss" shall herein mean damage or destruction
which was caused by an event required to be covered by the insurance described
in paragraph 8.

         9.2 Partial Damage - Insured Loss. Subject to the provisions of
paragraphs 9.4, 9.5 and 9.6, if at any time during the term of this Lease there
is damage which is an insured Loss and which falls into the classification of
Premises Partial Damage or Premises Building Partial Damage, then Lessor shall,
at Lessor's expense, repair such damage, but not Lessee's fixtures, equipment or
tenant improvements unless the same have become a part of the Premises pursuant
to Paragraph 7.5 hereof as soon as reasonably possible and this Lease shall
continue in full force and effect. Lessor shall make such repairs as soon as
reasonably possible and this Lease shall continue in full force and effect.

         9.3 Partial Damage - Uninsured Loss. Subject to the provisions of
Paragraphs 9.4, 9.5 and 9.6, if at any time during the term of this Lease there
is damage which is not an Insured Loss and which falls within the classification
of Premises Partial Damage or Premises Building Partial Damage, unless caused by
a negligent or willful act of Lessee (in which event Lessee shall make the
repairs at Lessee's expense), Lessor may at Lessor's option either (i) repair
such damage as soon as reasonably possible at Lessor's expense, in which event
this Lease shall continue in full force and effect, or (ii) give written notice
to Lessee within thirty (30) days after the date of the occurrence of such
damage of Lessor's intention to cancel and terminate this Lease, as of the date
of the occurrence of such damage. In the event Lessor elects to give such notice
of Lessor's intention to cancel and terminate this Lease, Lessee shall have the
right within ten (10) days after the receipt of such notice to give written
notice to Lessor of Lessee's intention to repair such damage at Lessee's
expense, without reimbursement from Lessor, in which event this Lease shall
continue in full force and effect, and Lessee shall proceed to make such repairs
as soon as reasonably possible. If Lessee does not give such notice within such
10-day period this Lease shall be cancelled and terminated as of the date of the
occurrence of such damage.

         9.4 Total Destruction. If at any time during the term of this Lease
there is damage, whether or not an Insured Loss, (including destruction required
by any authorized public authority), which falls into the classification of
Premises Total Destruction or Premises Building Total Destruction, this Lease
shall automatically terminate as of the date of such total destruction.

         9.5  Damage Near End of Term

                  (a) If at any time during the last six months of the term of
this Lease there is damage, whether or not an Insured Loss, which falls within
the classification of Premises Partial Damage, Lessor or Lessee may at Lessee's
and/or Lessor's option cancel and terminate this Lease as of the date of
occurrence of such damage by giving written notice to the other party, of such
party's election to do so within 30 days after the date of occurrence of such
damage.

                  (b) Notwithstanding paragraph 9.5(a), in the event that Lessee
has an option to extend or renew this Lease, and the time within which said
option may be exercised has not yet expired, Lessee shall exercise such option,
if it is to be exercised at all, no later than 20 days after the occurrence of
an Insured Loss falling within the classification of Premises Partial Damage
during the last six months of the term of this Lease. If Lessee duly exercises
such option during said 20 day period, Lessor shall, at Lessor's expense, repair
such damage as soon as reasonably possible and this Lease shall continue in full
force and effect. If Lessee fails to exercise such option during said 20 day
period, then Lessor may at Lessor's option terminate and cancel this Lease as of
the expiration of said 20 day period by giving written notice to Lessee of
Lessor's election to do so within 10 days after the expiration of said 20 day
period, notwithstanding any term or provision in the grant of option to the
contrary.

         9.6  Abatement of Rent; Lessee's Remedies

                  (a) In the event of damage described in paragraphs 9.2 or 9.3,
and Lessor or Lessee repairs or restores the Premises pursuant to the provisions
of this Paragraph 9, the rent payable hereunder for the period during which such
damage, repair or restoration continues shall be abated in proportion to the
degree to which Lessee's use of the Premises is impaired. Except for abatement
of rent, if any, Lessee shall have no claim against Lessor for any damage
suffered by reason of any such damage, destruction, repair or restoration.

                  (b) If Lessor shall be obligated to repair or restore the
Premises under the provisions of this Paragraph 9 and shall not commence such
repair or restoration within 90 days after such obligations shall accrue, Lessee
may at Lessee's option cancel and terminate this Lease by giving Lessor written
notice of Lessee's election to do so at any time prior to the commencement of
such repair or restoration. In such event this Lease shall terminate as of the
date of such notice.

         9.7 Termination - Advance Payments. Upon termination of this Lease
pursuant to this Paragraph 9, an equitable adjustment shall be made concerning
advance rent and any advance payments made by Lessee to Lessor. Lessor shall, in
addition, return to Lessee so much of Lessee's security deposit as has not
theretofore been applied by Lessor.

         9.8 Waiver. Lessor and Lessee waive the provisions of any statutes
which relate to termination of leases when leased property is destroyed and
agree that such event shall be governed by the terms of this Lease.

10.  Real Property Taxes.

         10.1 Payment of Taxes. Lessee shall pay the real property tax, as
defined in paragraph 10.2, applicable to the Premises during the term of this
Lease. All such payments shall be made at least ten (10) days prior to the
delinquency date of such payment. Lessee shall promptly furnish Lessor with
satisfactory evidence that such taxes have been paid. If any such taxes paid by
Lessee shall cover any period of time prior to or after the expiration of the
term hereof, Lessee's share of such taxes shall be equitably prorated to cover
only the period of time within the tax fiscal year during which this Lease shall
be in effect, and Lessor shall reimburse Lessee to the extent required. If
Lessee shall fail to pay any such taxes, Lessor shall have the right to pay the
same, in which case Lessee shall repay such amount to Lessor with Lessee's next
rent installment together with interest at the maximum rate then allowable by
law.

         10.2 Definition of "Real Property Tax". As used herein, the term "real
property tax" shall include any form of real estate tax or assessment, general,
special, ordinary or extraordinary, and any license fee, commercial rental tax,
improvement bond or bonds, levy or tax (other than inheritance, personal income
or estate taxes) imposed on the Premises by any authority having the direct or
indirect power to tax, including any city, state or federal government, or any
school, agricultural, sanitary, fire, street, drainage or other improvement
district thereof, as against any legal or equitable interest of Lessor in the
Premises or in the real property of which the Premises are a part, as against
Lessor's right to rent or other income therefrom, and as against Lessor's
business of leasing the Premises. The term "real property tax" shall also
include any tax, fee, levy, assessment or charge (i) in substitution of,
partially or totally, any tax, fee, levy, assessment or charge hereinabove
included within the definition of "real property tax," or (ii) the nature of
which was hereinbefore included within the definition of "real property tax," or
(iii) which is imposed for a service or right not charged prior to June 1, 1978,
or, if previously charged, has been increased since June 1, 1978, or (iv) which
is imposed by reason of this transaction, any modifications or changes hereto or
any transfers hereof.

         10.3 Joint Assessment. If the Premises are not separately assessed,
Lessee's liability shall be an equitable proportion of the real property taxes
for all of the land and improvements included within the tax parcel assessed,
such proportion to be determined by Lessor from the respective valuations
assigned in the assessor's work sheets or such other information as may be
reasonably available. Lessor's reasonable determination thereof, in good faith,
shall be conclusive.

         10.4  Personal Property Taxes.

                  (a) Lessee shall pay prior to delinquency all taxes assessed
against and levied upon trade fixtures, furnishings, equipment and all other
personal property of Lessee contained in the Premises or elsewhere. When
possible, Lessee shall cause said trade fixtures, furnishings, equipment and all
other personal property to be assessed and billed separately from the real
property of Lessor.

                  (b) If any of Lessee's said personal property shall be
assessed with Lessor's real property, Lessee shall pay Lessor the taxes
attributable to Lessee within 10 days after receipt of a written statement
setting forth the taxes applicable to Lessee's property.

11. Utilities. Lessee shall pay for all water, gas, heat, light, power,
telephone and other utilities and services supplied to the Premises, together
with any taxes thereon. If any such services are not separately metered to
Lessee, Lessee shall pay a reasonable proportion to be determined by Lessor of
all charges jointly metered with other premises.

12.  Assignment and Subletting.

         12.1 Lessor's Consent Required. Lessee shall not voluntarily or by
operation of law assign, transfer, mortgage, sublet, or otherwise transfer or
encumber all or any part of Lessee's interest in this Lease or in the Premises,
without Lessor's prior written consent, which Lessor shall not unreasonably
withhold. Lessor shall respond to Lessee's request for consent hereunder in a
timely manner and any attempted assignment, transfer, mortgage, encumbrance or
subletting without such consent shall be void, and shall constitute a breach of
this Lease.

         12.2 Lessee Affiliate. Notwithstanding the provisions of paragraph 12.1
hereof, Lessee may assign or sublet the Premises, or any portion thereof,
without Lessor's consent, to any corporation which controls, is controlled by or
is under common control with Lessee, or to any corporation resulting from the
merger or consolidation with Lessee, or to any person or entity which acquires
all the assets of Lessee as a going concern of the business that is being
conducted on the Premises, provided that said assignee assumes, in full, the
obligations of Lessee under this Lease. Any such assignment shall not, in any
way, affect or limit the liability of Lessee under the terms of this Lease even
if after such assignment or subletting the terms of this Lease are materially
changed or altered without the consent of Lessee, the consent of whom shall not
be necessary.

         12.3 No Release of Lessee. Regardless of Lessor's consent, no
subletting or assignment shall release Lessee of Lessee's obligation or alter
the primary liability of Lessee to pay the rent and to perform all other
obligations to be performed by Lessee hereunder. The acceptance of rent by
Lessor from any other person shall not be deemed to be a waiver by Lessor of any
provision hereof. Consent to one assignment or subletting shall not be deemed
consent to any subsequent assignment or subletting. In the event of default by
any assignee of Lessee or any successor of Lessee, in the performance of any of
the terms hereof, Lessor may proceed directly against Lessee without the
necessity of exhausting remedies against said assignee. Lessor may consent to
subsequent assignments or subletting of this Lease or amendments or
modifications to this Lease with assignees

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of Lessee, without notifying Lessee, or any successor of Lessee, and without
obtaining its or their consent thereto and such action shall not relieve Lessee
of liability under this Lease.

         12.4 Attorney's Fees. In the event Lessee shall assign or sublet the
Premises or request the consent of Lessor to any assignment or subletting or if
Lessee shall request the consent of Lessor for any act Lessee proposes to do
then Lessee shall pay Lessor's reasonable attorneys fees incurred in connection
therewith, such attorneys fees not to exceed $350.00 for each such request.

13.  Defaults; Remedies.

         13.1 Defaults. The occurrence of any one or more of the following
events shall constitute a material default and breach of this Lease by Lessee:

                  (a)  The vacating or abandonment of the Premises by Lessee.

                  (b) The failure by Lessee to make any payment of rent or any
other payment required to be made by Lessee hereunder, as and when due, where
such failure shall continue for a period of three days after written notice
thereof from Lessor to Lessee. In the event that Lessor serves Lessee with a
Notice to Pay Rent or Quit pursuant to applicable Unlawful Detainer statutes
such Notice to Pay Rent or Quit shall also constitute the notice required by
this subparagraph.

                  (c) The failure by Lessee to observe or perform any of the
covenants, conditions or provisions of this Lease to be observed or performed by
Lessee, other than described in paragraph (b) above, where such failure shall
continue for a period of 30 days after written notice thereof from Lessor to
Lessee; provided, however, that if the nature of Lessee's default is such that
more than 30 days are reasonably required for its cure, then Lessee shall not be
deemed to be in default if Lessee commenced such cure within said 30-day period
and thereafter diligently prosecutes such cure to completion.

                  (d) (i) The making by Lessee of any general arrangement or
assignment for the benefit of creditors; (ii) Lessee becomes a "debtor" as
defined in 11 U.S.C. 101 or any successor statute thereto (unless, in the case
of a petition filed against Lessee, the same is dismissed within 60 days); (iii)
the appointment of a trustee or receiver to take possession of substantially all
of Lessee's assets located at the Premises or of Lessee's interest in this
Lease, where possession is not restored to Lessee within 30 days; or (iv) the
attachment, execution or other judicial seizure of substantially all of Lessee's
assets located at the Premises or of Lessee's interest in this Lease, where such
seizure is not discharged within 30 days. Provided, however, in the event that
any provision of this paragraph 13.1(d) is contrary to any applicable law, such
provision shall be of no force or effect.

                  (e) The discovery by Lessor that any financial statement given
to Lessor by Lessee, any assignee of Lessee, any subtenant of Lessee, any
successor in interest of Lessee or any guarantor of Lessee's obligation
hereunder, and any of them, was materially false.

         13.2 Remedies. In the event of any such material default or breach by
Lessee, Lessor may at any time thereafter, with or without notice or demand and
without limiting Lessor in the exercise of any right or remedy which Lessor may
have by reason of such default or breach:

                  (a) Terminate Lessee's right to possession of the Premises by
any lawful means, in which case this Lease shall terminate and Lessee shall
immediately surrender possession of the Premises to Lessor. In such event Lessor
shall be entitled to recover from Lessee all damages incurred by Lessor by
reason of Lessee's default including, but not limited to, the cost of recovering
possession of the Premises; expenses of reletting, including necessary
renovation and alteration of the Premises, reasonable attorney's fees, and any
real estate commission actually paid; the worth at the time of award by the
court having jurisdiction thereof of the amount by which the unpaid rent for the
balance of the term after the time of such award exceeds the amount of such
rental loss for the same period that Lessee proves could be reasonably avoided;
that portion of the leasing commission paid by Lessor pursuant to Paragraph 15
applicable to the unexpired term of this Lease.

                  (b) Maintain Lessee's right to possession in which case this
Lease shall continue in effect whether or not Lessee shall have abandoned the
Premises. In such event Lessor shall be entitled to enforce all of Lessor's
rights and remedies under this Lease, including the right to recover the rent as
it becomes due hereunder.

                  (c) Pursue any other remedy now or hereafter available to
Lessor under the laws or judicial decisions of the state wherein the Premises
are located. Unpaid installments of rent and other unpaid monetary obligations
of Lessee under the terms of this Lease shall bear interest from the date due at
the maximum rate then allowable by law.

         13.3 Default by Lessor. Lessor shall not be in default unless Lessor
fails to perform obligations required of Lessor within a reasonable time, but in
no event later than thirty (30) days after written notice by Lessee to Lessor
and to the holder of any first mortgage or deed of trust covering the Premises
whose name and address shall have theretofore been furnished to Lessee in
writing, specifying wherein Lessor has failed to perform such obligation;
provided, however, that if the nature of Lessor's obligation is such that more
than thirty (30) days are required for performance then Lessor shall not be in
default if Lessor commences performance within such 30-day period and thereafter
diligently prosecutes the same to completion.

         13.4 Late Charges. Lessee hereby acknowledges that late payment by
Lessee to Lessor of rent and other sums due hereunder will cause Lessor to incur
costs not contemplated by this Lease, the exact amount of which will be
extremely difficult to ascertain. Such costs include, but are not limited to,
processing and accounting charges, and late charges which may be imposed on
Lessor by the terms of any mortgage or trust deed covering the Premises.
Accordingly, if any installment of rent or any other sum due from Lessee shall
not be received by Lessor or Lessor's designee within ten (10) days after such
amount shall be due, then, without any requirement for notice to Lessee, Lessee
shall pay to Lessor a late charge equal to 6% of such overdue amount. The
parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Lessor will incur by reason of late payment by Lessee.
Acceptance of such late charge by Lessor shall in no event constitute a waiver
of Lessee's default with respect to such overdue amount, nor prevent Lessor from
exercising any of the other rights and remedies granted hereunder. In the event
that a late charge is payable hereunder, whether or not collected, for three (3)
consecutive installments of rent, then rent shall automatically become due and
payable quarterly in advance, rather than monthly, notwithstanding paragraph 4
or any other provision of this Lease to the contrary.

         13.5 Impounds. In the event that a late charge is payable hereunder,
whether or not collected, for three (3) installments of rent or any other
monetary obligation of Lessee under the terms of this Lease, Lessee shall pay to
Lessor, if Lessor shall so request, in addition to any other payments required
under this Lease, a monthly advance installment, payable at the same time as the
monthly rent, as estimated by Lessor, for real property tax and insurance
expenses on the Premises which are payable by Lessee under the terms of this
Lease. Such fund shall be established to insure payment when due, before
delinquency, of any or all such real property taxes and insurance premiums. If
the amounts paid to Lessor by Lessee under the provisions of this paragraph are
insufficient to discharge the obligations of Lessee to pay such real property
taxes and insurance premiums as the same become due, Lessee shall pay to Lessor,
upon Lessor's demand, such additional sums necessary to pay such obligations.
All moneys paid to Lessor under this paragraph may be intermingled with other
moneys of Lessor and shall not bear interest. In the event of a default in the
obligations of Lessee to perform under this Lease, then any balance remaining
from funds paid to Lessor under the provisions of this paragraph may, at the
option of Lessor, be applied to the payment of any monetary default of Lessee in
lieu of being applied to the payment of real property tax and insurance
premiums.

14. Condemnation. If the Premises or any portion thereof are taken under the
power of eminent domain, or sold under the threat of the exercise of said power
(all of which are herein called "condemnation"), this Lease shall terminate as
to the part so taken as of the date the condemning authority takes title or
possession, whichever first occurs. If more than 10% of the floor area of the
building on the Premises, or more than 25% of the land area of the Premises
which is not occupied by any building, is taken by condemnation, Lessee may, at
Lessee's option, to be exercised in writing only within ten (10) days after
Lessor shall have given Lessee written notice of such taking (or in the absence
of such notice, within ten (10) days after the condemning authority shall have
taken possession) terminate this Lease as of the date the condemning authority
takes such possession. If Lessee does not terminate this Lease in accordance
with the foregoing, this Lease shall remain in full force and effect as to the
portion of the Premises remaining, except that the rent shall be reduced in the
proportion that the floor area of the building taken bears to the total floor
area of the building situated on the Premises. No reduction of rent shall occur
if the only area taken is that which does not have a building located thereon.
Any award for the taking of all or any part of the Premises under the power of
eminent domain or any payment made under threat of the exercise of such power
shall be the property of Lessor, whether such award shall be made as
compensation for diminution in value of the leasehold or for the taking of the
fee, or as severance damages; provided, however, that Lessee shall be entitled
to any award for loss of or damage to Lessee's trade fixtures and removable
personal property. In the event that this Lease is not terminated by reason of
such condemnation, Lessor shall to the extent of severance damages received by
Lessor in connection with such condemnation, repair any damage to the Premises
caused by such condemnation except to the extent that Lessee has been reimbursed
therefor by the condemning authority. Lessee shall pay any amount in excess of
such severance damages required to complete such repair.

15.  Broker's Fee.

                  (a) Upon execution of this Lease by both parties, Lessor shall
pay to (blank) Licensed real estate broker(s) a fee as set forth in a separate
agreement between Lessor and said broker(s), or in the event there is no
separate agreement between Lessor and said broker(s), the sum of $(blank), for
brokerage services rendered by said broker(s) to Lessor in this transaction.

                  (b) Lessor further agrees that if Lessee exercises any Option
as defined in paragraph 39.1 of this Lease, which is granted to Lessee under
this Lease, or any subsequently granted option which is substantially similar to
an Option granted to Lessee under this Lease, or if Lessee acquires any rights
to the Premises or other premises described in this Lease which are
substantially similar to what Lessee would have acquired had an Option herein
granted to Lessee been exercised, or if Lessee remains in possession of the
Premises after the expiration of the term of this Lease after having failed to
exercise an Option, or if said broker(s) are the procuring cause of any other
lease or sale entered into between the parties pertaining to the Premises and/or
any adjacent property in which Lessor has an interest, then as to any of said
transactions, Lessor shall pay said broker(s) a fee in accordance with the
schedule of said broker(s) in effect at the time of execution of this Lease.

                  (c) Lessor agrees to pay said fee not only on behalf of Lessor
but also on behalf of any person, corporation, association, or other entity
having an ownership interest in said real property or any part thereof, when
such fee is due hereunder. Any transferee of Lessor's interest in this Lease,
whether such transfer is by agreement or by operation of law, shall be deemed to
have assumed Lessor's obligation under this Paragraph 15. Said broker shall be a
third party beneficiary of the provisions of this Paragraph 15.

16.  Estoppel Certificate.

         (a) Lessee shall at any time upon not less than ten (10) days' prior
written notice from Lessor execute, acknowledge and deliver to Lessor a
statement in writing (i) certifying that this Lease is unmodified and in full
force and effect (or, if modified, stating the nature of such modification and
certifying that this Lease, as so modified, is in full force and effect) and the
date to which the rent and other charges are paid in advance, if any, and (ii)
acknowledging that there are not, to Lessee's knowledge, any uncured defaults on
the part of Lessor hereunder, or specifying such defaults if any are claimed.
Any such statement may be conclusively relied upon by any prospective purchaser
or encumbrancer of the Premises.

         (b) At Lessor's option, Lessee's failure to deliver such statement
within such time shall be a material breach of this Lease or shall be

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conclusive upon Lessee (i) that this Lease is in full force and effect, without
modification except as may be represented by Lessor, (ii) that there are no
uncured defaults in Lessor's performance, and (iii) that not more than one
month's rent has been paid in advance or such failure may be considered by
Lessor as a default by Lessee under this Lease.
         (c) If Lessor desires to finance, refinance, or sell the Premises, or
any part thereof, Lessee hereby agrees to deliver to any lender or purchaser
designated by Lessor such financial statements of Lessee as may be reasonably
required by such lender or purchaser. Such statements shall include the past
three years' financial statements of Lessee. All such financial statements shall
be received by Lessor and such lender or purchaser in confidence and shall be
used only for the purposes herein set forth.

17.  (Deleted)

18. Severability. The invalidity of any provision of this Lease as determined by
a court of competent jurisdiction, shall in no way affect the validity of any
other provision hereof.

19. Interest on Past-due Obligations. Except as expressly herein provided, any
amount due to Lessor not paid when due shall bear interest at the maximum rate
then allowable by law from the date due. Payment of such interest shall not
excuse or cure any default by Lessee under this Lease, provided, however, that
interest shall not be payable on late charges incurred by Lessee nor on any
amounts upon which late charges are paid by Lessee.

20. Time of Essence. Time is of the essence.

21. Additional Rent. Any monetary obligations of Lessee to Lessor under the
terms of this Lease shall be deemed to be rent.

22. Incorporation of Prior Agreements; Amendments. This Lease contains all
agreements of the parties with respect to any matter mentioned herein. No prior
agreement or understanding pertaining to any such matter shall be effective.
This Lease may be modified in writing only, signed by the parties in interest at
the time of the modification. Except as otherwise stated in this Lease, Lessee
hereby acknowledges that neither the real estate broker listed in Paragraph 15
hereof nor any cooperating broker on this transaction nor the Lessor or any
employees or agents of any of said persons has made any oral or written
warranties or representations to Lessee relative to the condition or use by
Lessee of said Premises and Lessee acknowledges that Lessee assumes all
responsibility regarding the Occupational Safety Health Act, the legal use and
adaptability of the Premises and the compliance thereof with all applicable laws
and regulations in effect during the term of this Lease except as otherwise
specifically stated in this Lease.

23. Notices. Any notice required or permitted to be given hereunder shall be in
writing and may be given by personal delivery or by certified mail, and if given
personally or by mail, shall be deemed sufficiently given if addressed to Lessee
or to Lessor at the address noted below the signature of the respective parties,
as the case may be. Either party may by notice to the other specify a different
address for notice purposes except that upon Lessee's taking possession of the
Premises, the Premises shall constitute Lessee's address for notice purposes. A
copy of all notices required or permitted to be given to Lessor hereunder shall
be concurrently transmitted to such party or parties at such addresses as Lessor
may from time to time hereafter designate by notice to Lessee.

24. Waivers. No waiver by Lessor or any provision hereof shall be deemed a
waiver of any other provision hereof or of any subsequent breach by Lessee of
the same or any other provision. Lessor's consent to, or approval of, any act
shall not be deemed to render unnecessary the obtaining of Lessor's consent to
or approval of any subsequent act by Lessee. The acceptance of rent hereunder by
Lessor shall not be a waiver of any preceding breach by Lessee of any provision
hereof, other than the failure of Lessee to pay the particular rent so accepted,
regardless of Lessor's knowledge of such preceding breach at the time of
acceptance of such rent.

25. Recording. Either Lessor or Lessee shall, upon request of the other,
execute, acknowledge and deliver to the other a "short form" memorandum of this
Lease for recording purposes.

26. Holding Over. If Lessee, with Lessor's consent, remains in possession of the
Premises or any part thereof after the expiration of the term hereof, such
occupancy shall be a tenancy from month to month upon all the provisions of this
Lease pertaining to the obligations of Lessee, but all options and rights of
first refusal, if any, granted under the terms of this Lease shall be deemed
terminated and be of no further effect during said month to month tenancy.

27. Cumulative Remedies. No remedy or election hereunder shall be deemed
exclusive but shall, wherever possible, be cumulative with all other remedies at
law or in equity.

28. Covenants and Conditions. Each provision of this Lease performable by Lessee
shall be deemed both a covenant and a condition.

29. Binding Effect; Choice of Law. Subject to any provisions hereof restricting
assignment or subletting by Lessee and subject to the provisions of Paragraph
17, this Lease shall bind the parties, their personal representatives,
successors and assigns. This Lease shall be governed by the laws of the State
wherein the Premises are located.

30.  Subordination.
         (a) This Lease, at Lessor's option, shall be subordinate to any ground
lease, mortgage, deed of trust, or any other hypothecation or security now or
hereafter placed upon the real property of which the Premises are a part and to
any and all advances made on the security thereof and to all renewals,
modifications, consolidations, replacements and extensions thereof.
Notwithstanding such subordination, Lessee's right to quiet possession of the
Premises shall not be disturbed if Lessee is not in default and so long as
Lessee shall pay the rent and observe and perform all of the provisions of this
Lease, unless this Lease is otherwise terminated pursuant to its terms. If any
mortgagee, trustee or ground lessor shall elect to have this Lease prior to the
lien of its mortgage, deed of trust or ground lease, and shall give written
notice thereof to Lessee, this Lease shall be deemed prior to such mortgage,
deed of trust, or ground lease, whether this Lease is dated prior or subsequent
to the date of said mortgage, deed of trust or ground lease or the date of
recording thereof.

         (b) Lessee agrees to execute any documents required to effectuate an
attornment, a subordination or to make this Lease prior to the lien of any
mortgage, deed of trust or ground lease, as the case may be. Lessee's failure to
execute such documents within 10 days after written demand shall constitute a
material default by Lessee hereunder, or, at Lessor's option, Lessor shall
execute such documents on behalf of Lessee as Lessee's attorney-in-fact. Lessee
does hereby make, constitute and irrevocably appoint Lessor as Lessee's
attorney-in-fact and in Lessee's name, place and stead, to execute such
documents in accordance with this paragraph 30(b).

31. Attorney's Fees. If either party or the broker named herein brings an action
to enforce the terms hereof or declare rights hereunder, the prevailing party in
any such action, on trial or appeal, shall be entitled to his reasonable
attorney's fees to be paid by the losing party as fixed by the court. The
provisions of this paragraph shall inure to the benefit of the broker named
herein who seeks to enforce a right hereunder.

32. Lessor's Access. Lessor and Lessor's agents shall have the right to enter
the Premises at reasonable times for the purpose of inspecting the same, showing
the same to prospective purchasers, lenders, or lessees, and making such
alterations, repairs, improvements or additions to the Premises or to the
building of which they are a part as Lessor may deem necessary or desirable.
Lessor may at any time place on or about the Premises any ordinary "For Sale"
signs and Lessor may at any time during the last 120 days of the term hereof
place on or about the Premises any ordinary "For Lease" signs, all without
rebate of rent or liability to Lessee.

33. Auctions. Lessee shall not conduct, nor permit to be conducted, either
voluntarily or involuntarily, any auction upon the Premises without first having
obtained Lessor's prior written consent. Notwithstanding anything to the
contrary in this Lease, Lessor shall not be obligated to exercise any standard
of reasonableness in determining whether to grant such consent.

34. Signs. Lessee shall not place any sign upon the Premises without Lessor's
prior written consent except that Lessee shall have the right, without the prior
permission of Lessor to place ordinary and usual for rent or sublet signs
thereon.

35. Merger. The voluntary or other surrender of this Lease by Lessee, or a
mutual cancellation thereof, or a termination by Lessor, shall not work a
merger, and shall, at the option of Lessor, terminate all or any existing
subtenancies or may, at the option of Lessor, operate as an assignment to Lessor
of any or all of such subtenancies.

36. Consents. Except for paragraph 33 hereof, wherever in this Lease the consent
of one party is required to an act of the other party such consent shall not be
unreasonably withheld.

37. Guarantor. In the event that there is a guarantor of this Lease, said
guarantor shall have the same obligations as Lessee under this Lease.

38. Quiet Possession. Upon Lessee paying the rent for the Premises and observing
and performing all of the covenants, conditions and provisions on Lessee's part
to be observed and performed hereunder, Lessee shall have quiet possession of
the Premises for the entire term hereof subject to all of the provisions of this
Lease. The individuals executing this Lease on behalf of Lessor represent and
warrant to Lessee that they are fully authorized and legally capable of
executing this Lease on behalf of Lessor and that such execution is binding upon
all parties holding an ownership interest in the Premises.

39.  Options.

         39.1 Definition. As used in this paragraph the word "Options" has the
following meaning: (1) the right or option to extend the term of this Lease or
to renew this Lease or to extend or renew any lease that Lessee has on other
property of Lessor; (2) the option or right of first refusal to lease the
Premises or the right of first offer to lease the Premises or the right of first
refusal to lease other property of Lessor or the right of first offer to lease
other property of Lessor; (3) the right or option to purchase the Premises, or
the right of first refusal to purchase the Premises, or the right of first offer
to purchase the Premises or the right or option to purchase other property of
Lessor, or the right of first refusal to purchase other property of Lessor or
the right of first offer to purchase other property of Lessor.

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         39.2 Options Personal. Each Option granted to Lessee in this Lease are
personal to Lessee and may not be exercised or be assigned, voluntarily or
involuntarily, by or to any person or entity other than Lessee, provided,
however, the Option may be exercised by or assigned to any Lessee Affiliate as
defined in paragraph 12.2 of this Lease. The Options herein granted to Lessee
are not assignable separate and apart from this Lease.

         39.3 Multiple Options. In the event that Lessee has any multiple
options to extend or renew this Lease a later option cannot be exercised unless
the prior option to extend or renew this Lease has been so exercised.

         39.4  Effect of Default on Options.

                  (a) Lessee shall have no right to exercise an Option,
notwithstanding any provision in the grant of Option to the contrary, (i) during
the time commencing from the date Lessor gives to Lessee a notice of default
pursuant to paragraph 13.1(b) or 13.1(c) and continuing until the default
alleged in said notice of default is cured, or (ii) during the period of time
commencing on the day after a monetary obligation to Lessor is due from Lessee
and unpaid (without any necessity for notice thereof to Lessee) continuing until
the obligation is paid, or (iii) at any time after an event of default described
in paragraphs 13.1(a), 13.1(d), or 13.1(e) (without any necessity of Lessor to
give notice of such default to Lessee), or (iv) in the event that Lessor has
given to Lessee three or more notices of default under paragraph 13.1(b), where
a late charge has become payable under paragraph 13.4 for each of such defaults,
or paragraph 13.1(c), whether or not the defaults are cured, during the 12 month
period prior to the time that Lessee intends to exercise the subject Option.

                  (b) The period of time within which an Option may be exercised
shall not be extended or enlarged by reason of Lessee's inability to exercise an
Option because of the provisions of paragraph 39.4(a).

                  (c) All rights of Lessee under the provisions of an Option
shall terminate and be of no further force or effect, notwithstanding Lessee's
due and timely exercise of the Option, if, after such exercise and during the
term of this Lease, (i) Lessee fails to pay to Lessor a monetary obligation of
Lessee for a period of 30 days after such obligation becomes due (without any
necessity of Lessor to give notice thereof to Lessee), or (ii) Lessee fails to
commence to cure a default specified in paragraph 13.1(c) within 30 days after
the date that Lessor gives notice to Lessee of such default and/or Lessee fails
thereafter to diligently prosecute said cure to completion, or (iii) Lessee
commits a default described in paragraph 13.1(a), 13,1(d) or 13.1 (e) (without
any necessity of Lessor to give notice of such default to Lessee), or (iv)
Lessor gives to Lessee three or more notices of default under paragraph 13.1(b),
where a late charge becomes payable under paragraph 13.4 for each such default,
or paragraph 13.1(c), whether or not the defaults are cured.

40. Multiple Tenant Building. In the event that the Premises are part of a
larger building or group of buildings then Lessee agrees that it will abide by,
keep and observe all reasonable rules and regulations which Lessor may make from
time to time for the management, safety, care, and cleanliness of the building
and grounds, the parking of vehicles and the preservation of good order therein
as well as for the convenience of other occupants and tenants of the building.
The violations of any such rules and regulations shall be deemed a material
breach of this Lease by Lessee.

41. Security Measures. Lessee hereby acknowledges that the rental payable to
Lessor hereunder does not include the cost of guard service or other security
measures, and that Lessor shall have no obligation whatsoever to provide same.
Lessee assumes all responsibility for the protection of Lessee, its agents and
invitees from acts of third parties.

42. Easements. Lessor reserves to itself the right, from time to time, to grant
such easements, rights and dedications that Lessor deems necessary or desirable,
and to cause the recordation of Parcel Maps and restrictions, so long as such
easements, rights, dedications, Maps and restrictions do not unreasonably
interfere with the use of the Premises by Lessee. Lessee shall sign any of the
aforementioned documents upon request of Lessor and failure to do so shall
constitute a material breach of this Lease.

43. Performance Under Protest. If at any time a dispute shall arise as to any
amount or sum of money to be paid by one party to the other under the provisions
hereof, the party against whom the obligation to pay the money is asserted shall
have the right to make payment "under protest" and such payment shall not be
regarded as a voluntary payment, and there shall survive the right on the part
of said party to institute suit for recovery of each sum. If it shall be
adjudged that there was no legal obligation on the part of said party to pay
such sum or any part thereof, said party shall be entitled to recover such sum
or so much thereof as it was not legally required to pay under the provisions of
this Lease.

44. Authority. If Lessee is a corporation, trust, or general or limited
partnership, each individual executing this Lease on behalf of such entity
represents and warrants that he or she is duly authorized to execute and deliver
this Lease on behalf of said entity. If Lessee is a corporation, trust or
partnership, Lessee shall, within thirty (30) days after execution of this
Lease, deliver to Lessor evidence of such authority satisfactory to Lessor.

45. Conflict. Any conflict between the printed provisions of this Lease and the
typewritten or handwritten provisions shall be controlled by the typewritten or
handwritten provisions.

46. Insuring Party. The insuring party under this lease shall be the XOMA
CORPORATION.

47. Addendum. Attached hereto is an addendum or addenda containing paragraphs
#48 through #51 which constitutes a part of this Lease.

LESSOR AND LESSEE HAVE CAREFULLY READ AND REVIEWED THIS LEASE AND EACH TERM AND
PROVISION CONTAINED HEREIN AND, BY EXECUTION OF THIS LEASE, SHOW THEIR INFORMED
AND VOLUNTARY CONSENT THERETO. THE PARTIES HEREBY AGREE THAT, AT THE TIME THIS
LEASE IS EXECUTED, THE TERMS OF THIS LEASE ARE COMMERCIALLY REASONABLE AND
EFFECTUATE THE INTENT AND PURPOSE OF LESSOR AND LESSEE WITH RESPECT TO THE
PREMISES.

IF THIS LEASE HAS BEEN FILLED IN IT HAS BEEN PREPARED FOR SUBMISSION TO YOUR
ATTORNEY FOR HIS APPROVAL. NO REPRESENTATION OR RECOMMENDATION IS MADE BY THE
AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION OR BY THE REAL ESTATE BROKER OR ITS
AGENTS OR EMPLOYEES AS TO THE LEGAL SUFFICIENCY, LEGAL EFFECT, OR TAX
CONSEQUENCES OF THIS LEASE OR THE TRANSACTION RELATING THERETO; THE PARTIES
SHALL RELY SOLELY UPON THE ADVICE OF THEIR OWN LEGAL COUNSEL AS TO THE LEGAL AND
TAX CONSEQUENCES OF THIS LEASE.

The parties hereto have executed this Lease at the place on the dates specified
immediately adjacent to their respective signatures.

Executed
By       Richard B. Gomez, Josephine L. Gomez
         TTEE-U/A/D   10-31-90, FBO Gomez Fam. Trust.
         /s/R. B. Gomez
         /s/J. L. Gomez
         "LESSOR"
Address: 13233 #F. Fiji Way
                  Marina del Rey, Ca.  90292
                  (310) 821-5869

Executed
By       XOMA CORPORATION
         /c/C. L. Dellio
         C.L. DELLIO
         SR. VICE PRESIDENT, OPERATIONS
         "LESSEE"
Address: 2910 Seventh St.
                  Berkley, Ca.  94710
<PAGE>
                          REFERENCE DATE June 22, 1992
                              Revised July 28, 1992

ADDENDUM TO LEASE

Re:      1701 Colorado Blvd. & 1553 17th. St.
         Santa Monica, Ca. 90404

         Between, Lessee;  Xoma Corporation
                  Lessor;  Richard B. Gomez, Josephine L. Gomez
                           U/A/D -10-31-90 Gomez Fam. Trust.

Paragraph         #48.0 Lease term to be January 1, 1993 through December 31,
                  1995. Lessee shall pay to Lessor as rent for premises in
                  advance on the first day of each month according to the
                  following schedule hereof.

                  From: February 1, 1993 To: December 31, 1993
                                             $11,500.00

                   From: January 1, 1994 To: December 31, 1994
                                             $12,075.00

                   From: January 1, 1995 To: December 31, 1995
                                             $12,679.00

Paragraph  #49.0 A security deposit of $27,300.00 is still in deposit with
           Lessor. Upon execution of said Lease, Lessor shall credit Lessee
           $11,500.00 (Eleven Thousand Five Hundred) and applied as rent for the
           first month's rent of this lease.

           A security deposit balance of $15,800.00 will remain in deposit with
           Lessor.



                                     PAGE #1
<PAGE>
                          REFERENCE DATE June 22, 1992
                              Revised July 28, 1992
ADDENDUM TO LEASE OPTION PERIOD

Re:  1701 Colorado Blvd. & 1553-17th St.
         Santa Monica, Ca.  90404

Paragraph         #50.0 The term and conditions of the OPTION
                  PERIOD shall be the same as the terms and
                  conditions prevailing during the term of
                  this Lease, with the following conditions.
                  (option for 24 months) The said option to
                  extend and renew the lease must be
                  exercised, if at all by notice in writing
                  given to Lessor not less than 90 days prior
                  to the expiration of the term hereof, and
                  may not be exercised at such time that
                  Lessee is in default under any provisions of
                  this lease.

                  Lessee and Lessor agree, that Lessee will pay then Lessor as
                  rent for premises in advance on the first day of each month,
                  according to the following schedule:

                  From: January 1, 1996 To: December 31, 1996
                                            $13,566.00

                  From: January 1, 1997 To: December 31, 1997
                                            $14,515.00

Paragraph         #51.0 Paragraph #10 remains as is, only to add clarification.
                  Lessee agrees to make each payment for reimbursement to Lessor
                  within ten (10) days from the date Lessor presents Lessee
                  copies of tax bills reflecting the assessments and amounts due
                  thereon.

The Lessee and Lessor agree that this Addendum attached hereto constitute a part
of said Lease containing Paragraphs #48- through #51.
                                                               Initials: /s/CLD
                                                                        /s/RBG
                                     PAGE #2






                                STANDARD SUBLEASE
                   AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION
                                   AIR (LOGO)

1. Parties. This Sublease, dated, for reference purposes only, January 20, 1997,
is made by and between UroGenesys, Inc. (herein called "Lessor") and XOMA
Corporation (herein called "Lessee").

2. Premises. Sublessor hereby leases to Sublessee and Sublessee hereby leases
from Sublessor for the term, at the rental, and upon all of the conditions set
forth herein, that certain real property situated in the County of Los Angeles,
State of California, commonly known as 1701 Colorado Ave. & 1553 17th St., Santa
Monica, CA 90404 and described as approximately One Thousand Two Hundred and
Fifty Square Feet (1,1250 square feet) portion of a larger premises only, of a
brick building at the aforementioned address. Said real property including the
land and all improvements therein, is herein called "the Premises".

3.  Term.

         3.1 Term. The term of this Sublease shall be for 3 years (36) months
commencing on March 1, 1997 and ending on February 29, 2000 unless sooner
terminated pursuant to any provision hereof.

         3.2 Delay in Commencement. Notwithstanding said commencement date, if
for any reason Sublessor cannot deliver possession of the Premises to Sublessee
on said date, Sublessor shall not be subject to any liability therefore, nor
shall such failure affect the validity of this Sublease or the obligations of
Sublessee hereunder or extend the term hereof, but in such case Sublessee shall
not be obligated to pay rent until possession of the Premises is tendered to
Sublessee; provided, however, that if Sublessor shall not have delivered
possession of the Premises within sixty (60) days from said commencement date,
Sublessee may, at Sublessee's option, by notice in writing to Sublessor within
ten (10) days thereafter, cancel this Sublease, in which event the parties shall
be discharged from all obligations thereunder. If Sublessee occupies the
Premises prior to said commencement date, such occupancy shall be subject to all
provisions hereof, such occupancy shall not advance the termination date, and
Sublessee shall pay rent for such period at the initial monthly rates set forth
below.

4. Rent. Sublessee shall pay to Sublessor as rent for the Premises equal monthly
payments of $1,437.50, in advance, on the 1st day of each month of the term
hereof. Sublease shall pay Sublessor upon the execution hereof $1,437.50 as rent
for March 1997. Rent for any period during the term hereof which is for less
than one month shall be a pro rata portion of the monthly installment. Rent
shall be payable in lawful money of the United States to Sublessor at the
address stated herein or to such other persons or at such other places as
Sublessor may designate in writing.

5. Security Deposit. Sublessee shall deposit with Sublessor upon execution
hereof $NIL as security for Sublessee's faithful performance of Sublessee's
obligations hereunder. If Sublessee fails to pay rent or other charges due
hereunder, or otherwise defaults with respect to any provision of this Sublease,
Sublessor may use, apply or retain all or any portion of said deposit for the
payment of any rent or other charge in default or for the payment of any other
sum to which Sublessor may become obligated by reason of Sublessee's default, or
to compensate Sublessor for any loss or damage which Sublessor may suffer
thereby. If Sublessor so uses or applies all or any portion of said deposit,
Sublessee shall within ten (10) days after written demand therefor deposit cash
with Sublessor in an amount sufficient to restore said deposit to the full
amount hereinabove stated and Sublessee's failure to do so shall be a material
breach of this Sublease. If the monthly rent shall, from time to time, increase
during the term of this Sublease, Sublessee shall thereupon deposit with
Sublessor additional security deposit so that the amount of security deposit
held by Sublessor shall at all times bear the same proportion to current rent as
the original security deposit bears the original monthly rent set forth in
paragraph 4 hereof. Sublessor shall not be required to keep said deposit
separate from its general accounts. If Sublessee performs all of Sublessee's
obligations hereunder, said deposit, or so much thereof as has not theretofore
been applied by Sublessor, shall be returned, without payment of interest or
other increment for its use, to Sublessee (or, at Sublessor's option, to that
last assignee, if any, of Sublessee's interest hereunder) at the expiration of
the term hereof, and after Sublessee has vacated the Premises. No trust
relationship is created herein between Sublessor and Sublessee with respect to
said Security Deposit.

6.  Use.

         6.1 Use. The Premises shall be used and occupied only for research,
laboratories and offices and related lawful uses and for no other purpose.

         6.2  Compliance with Law.
                  (a)  (deleted)
                  (b) Sublessee shall, at Sublessee's expense, comply promptly
with all applicable statutes, ordinances, rules, regulations, orders, covenants
and restrictions of record, and requirements in effect during the term or any
part of the term hereof, regulating the use by Sublessee of the Premises.
Sublessee shall not use nor permit the use of the Premises in any manner that
will tend to create waste or a nuisance or, if there shall be more than one
tenant in the building containing the Premises, shall tend to disturb such other
tenants.

         6.3 Condition of Premises. Sublessee hereby accepts the Premises in
their condition existing as of the execution hereof, subject to all applicable
zoning, municipal, county and state laws, ordinances and regulations governing
and regulating the use of the Premises, and accepts this Sublease subject
thereto and to all matters disclosed thereby and by any exhibits attached
hereto. Sublessee acknowledges that neither Sublessor nor Sublessor's agents has
made any representation or warranty as to the suitability of the Premises for
the conduct of Sublessee's business.

7.       Master Lease

         7.1 Sublessor is the lessee of the Premises by virtue of a lease,
hereinafter referred to as the "Master Lease", a copy of which is attached
hereto marked Exhibit 1, dated January 1991 wherein Richard B. Gomez and
Josephine L. Gomez, TTEE, U/A.D 10-31-1990 FBO Gomez Family Trust is the lessor,
hereinafter referred to as the "Master Lease".

         7.2 This Sublease is and shall be at all times subject and subordinate
to the Master Lease.

         7.3 The terms, conditions and respective obligations of Sublessor and
Sublessee to each other under this Sublease shall be the terms and conditions of
the Master Lease except for those provisions of the Master Lease which are
directly contradicted by this Sublease in which event the terms of this Sublease
document shall control over the Master Lease. Therefore, for the purpose of this
Sublease, wherever in the Master Lease the work "Lessor" is used it shall be
deemed to mean the Sublessor herein and wherever in the Master Lease the word
"Lessee" is used it shall be deemed to mean the Sublessee herein.

         7.4 During the term of this Sublease and for all periods subsequent for
obligations which have arisen prior to the termination of this Sublease,
Sublessee does hereby expressly assume and agree to perform and comply with, for
the benefit of Sublessor and Master Lessor, each and every obligation of
Sublessor under the Master Lease except for the following paragraphs which are
excluded therefrom: NIL.

                                                       /s/DBR  /s/WCM  1/20/97
<PAGE>
         7.5 The obligations that Sublessee has assumed under paragraph 7.4
hereof are hereinafter referred to as the "Sublessee's Assumed Obligations". The
obligations that Sublessee has not assumed under paragraph 7.4 hereof are
hereinafter referred to as the "Sublessor's Remaining Obligations".

         7.6 Sublessee shall hold Sublessor free and harmless of and from all
liability, judgments, costs, damages, claims or demands, including reasonable
attorneys fees, arising out of Sublessee's failure to comply with or perform
Sublessee's Assumed Obligations.

         7.7 Sublessor agrees to maintain the Master lease during the entire
term of this Sublease, subject, however, to any earlier termination of the
Master Lease without the fault of the Sublessor, and to comply with or perform
Sublessor's Remaining Obligations and to hold Sublessee free and harmless of an
from all liability, judgments, costs, damages, claims or demands arising out of
Sublessor's failure to comply with or perform Sublessor's Remaining Obligations.

         7.8 Sublessor represents that the Master Lease is in full force and
effect and that no default exists on the part of any party to the Master Lease.

8.       Assignment of Sublease and Default.

         8.1. Sublessor hereby assigns and transfer to Master Lessor the
Sublessor's interest in this Sublease and all rentals and income arising
therefrom, subject however to terms of Paragraph 8.2 hereof.

         8.2 Master Lessor, by executing this document, agrees that until a
default shall occur in the performance of the Sublessor's Obligations under the
Master Lease, that Sublessor may receive, collect and enjoy the rents accruing
under this Sublease. However, if Sublessor shall default in the performance of
its obligations to Master Lessor then master Lessor may, at its option, receive
and collect, directly from Sublessee, all rent owing and to be owed under this
Sublease. Master Lessor shall not, by reason of this assignment of the Sublease
nor by reason of the collection of the rents from the Sublessee, be deemed
liable to Sublessee for any failure of the Sublessor to perform and comply with
Sublessor's Remaining Obligations.

         8.3 Sublessor hereby irrevocably authorizes and directs Sublessee, upon
receipt of any written notice from the Master Lessor stating that a default
exists in the performance of Sublessor's obligations under the Master Lease, to
pay to Master Lessor the rents due and to become due under the Sublease.
Sublessor agrees that Sublessee shall have the right to rely upon any such
statement and request from Master Lessor, and that Sublessee shall pay such
rents to Master Lessor without any obligation or right to inquire as to whether
such default exists and notwithstanding any notice from or claim from Sublessor
to the contrary and Sublessor shall have no right or claim against Sublessee for
any such rents so paid by Sublessee.

         8.4 No changes or modifications shall be made to this Sublease without
the consent of Master Lessor.

9.       Consent of Master Lessor

         9.1 In the event that the Master Lease requires that Sublessor obtain
the consent of Master Lessor to any subletting by Sublessor then this Sublease
shall not be effective unless, within 10 days of the date hereof, Master Lessor
signs this Sublease thereby giving its consent to this Subletting.

         9.2 In the event that the obligations of the Sublessor under the Master
Lease have been guaranteed by third parties then this Sublease, nor the Master
Lessor's consent, shall not be effective unless, within 10 days of the date
hereof, said guarantors sign this Sublease thereby giving guarantors consent to
this Sublease and the terms hereof.

         9.3 In the event that Master Lessor does give such consent then:
                  (a) Such consent will not release Sublessor of its obligations
or alter the primary liability of Sublessor to pay the rent and perform and
comply with all of the obligations of Sublessor to be performed under the Master
Lease.
                  (b) The acceptance of rent by Master Lessor from Sublessee or
any one else liable under the Master Lease shall not be deemed a waiver by
Master Lessor of any provisions of the Master Lease.
                  (c) The consent to this Sublease shall not constitute a
consent to any subsequent subletting or assignment.
                  (d) In the event of any default of Sublessor under the Master
Lease, Master Lessor may proceed directly against Sublessor, any guarantors or
any one else liable under the Master Lease or this Sublease without first
exhausting Master Lessor's remedies against any other person or entity liable
thereon to Master Lessor.
                  (e)  (deleted)
                  (f) In the event that Sublessor shall default in its
obligations under the Master Lease, then Master Lessor, at its option and
without being obligated to do so, may require Sublessee to attorn to Master
Lessor in which event Master Lessor shall undertake the obligations of Sublessor
under this Sublease from the time of the exercise of said option to termination
of this Sublease but Master Lessor shall not be liable for any prepaid rents nor
any security deposit paid by Sublessee, nor shall Master Lessor be liable for
any other defaults of the Sublessor under the Sublease.

         9.4 The signatures of the Master Lessor and any Guarantors or Sublessor
at the end of this document shall constitute their consent to the terms of this
Sublease.

         9.5 Master Lessor acknowledges that, to the best of Master Lessor's
knowledge, no default presently exists under the Master Lease of obligations to
be performed by Sublessor and that the Master Lease is in full force and effect.

         9.6 In the event that Sublessor defaults under its obligations to be
performed under the Master Lease by Sublessor, Master Lessor agrees to deliver
to Sublessee a copy of any such notice of default. Sublessee shall have the
right to cure any default of Sublessor described in any notice of default within
ten days after service of such notice of default on Sublessee. If such default
is cured by Sublessee then Sublessee shall have the right of reimbursement and
offset from and against Sublessor.

10.      Brokers Fee.
         (deleted)

11. Attorney's fees. If any party named herein brings an action to enforce the
terms hereof or to declare rights hereunder, the prevailing party in any such
action, on trial and appeal, shall be entitled to his reasonable attorney's fees
to be paid by the losing party as fixed by the Court.

                                                     /s/DBR  /s/WCM  1/20/97
<PAGE>
12.  Additional Provision. See Addendum paragraphs 13 to 18 to Standard Sublease
     dated January 20, 1997.

IF THIS SUBLEASE HAS BEEN FILLED IN IT HAS BEEN PREPARED FOR SUBMISSION TO YOUR
ATTORNEY FOR HIS APPROVAL. NO REPRESENTATION OR RECOMMENDATION IS MADE BY THE
REAL ESTATE BROKER OR ITS AGENTS OR EMPLOYEES AS TO THE LEGAL SUFFICIENCY, LEGAL
EFFECT, OR TAX CONSEQUENCES OF THIS SUBLEASE OR THE TRANSACTION RELATING
THERETO.

Executed at Santa Monica
on (blank)                               By       /s/Donald B. Rice
address  1701 Colorado Avenue
         Santa Monica, CA 90404          UroGenesys, Inc., "Sublessor"

Executed at Santa Monica
on (blank)                               By       /s/W. Courtney McGregor
address  1545 17th Street
         Santa Monica, CA  90404         XOMA Corp., "Sublesee"

Executed at (blank)                     /s/R. B. Gomez  1/20/97
                                           "Guarantors"

                                                         /s/DBR  /s/WCM  1/20/97
<PAGE>
                              ADDENDUM TO SUBLEASE
                  BETWEEN UROGENESYS, INC. AND XOMA CORPORATION
                             DATED: JANUARY 20, 1997

13.      Sublessee shall be entitled to the use of the westerly storage sheds
         located in the parking area of Sublessor's premises. In addition to all
         requirements contained in the Master Lease regarding Hazardous
         Substances and Environmental Matters, Sublessee shall ensure that any
         chemicals or hazardous substances stored upon the subleased premises
         are stored, controlled and disposed of in conformity with all
         governmental requirements and standards.

14.      Sublessee shall comply with all insurance provisions of the referenced
         Master Lease, in respect of Sublessee's premises.

15.      Sublessor and Sublessee hereby agree that the list of laboratory
         equipment and systems identified in Exhibit I hereto shall be used
         jointly by Sublessee and Sublessor during the term of this Sublease and
         shall remain the property of Sublessee.

16.      The following space and/or equipment is to be shared without payment
         from either party to the other through February 29, 2000.
         Notwithstanding paragraphs 15 and 16, UroGenesys reserves the right to
         control access to shared equipment and areas located within its
         laboratory space, but shall ensure reasonable access to shared
         equipment and areas.

         a.       Back entrance to 1553 17th Street
         b.       Autoclaves in 1701 Colorado facility
         c.       Restrooms
         d.       Conference room and lunch room in 1545 17th Street
         e.       All parking spaces currently available to the facility
         f.       Ice machine
         g.       Custodial cleaning of floors in 1701 Colorado facility
         h.       Vacuum system
         i.       Deionized water system

17.      The following costs are to be shared as agreed to by the parties:

         a.       utilities and maintenance for the items in Exhibit I hereto; 
                  and
         b.       security systems

18.      Paragraph 6.2(e) of the Master Lease is hereby deleted. Sublessee
         agrees to indemnify, defend and hold Sublessor harmless for any and all
         claims, damages, fines, penalties, costs, and liabilities (including
         without limitation attorneys', consultants', and experts' fees)
         attributable to the use or ownership of the premises prior to the Start
         Date and the migration, presence, suspected presence or discharge of
         Hazardous Substances in, on or affecting the premises. This
         indemnification obligation shall include without limitation any costs
         of investigation, removal, remediation, restoration and/or abatement,
         and shall survive the expiration or termination of this Sublease.

         /s/DBR  /s/WCM  1/20/97
<PAGE>
         EXHIBIT I

         AMSCO 3030 Autoclave       Re:
         Vacuum System
         Deionized Water System
         Ice Machine
         Telephones

         /s/DBR  /s/WCM  1/20/97
<PAGE>
         APPENDIX A

         January 20, 1997

Donald B. Rice
UroGenesys, Inc.
1701 Colorado Avenue
Santa Monica, California  90404

     Re:  XOMA Continuing Obligations and Indemnity 1701 Colorado and 1553 17th
          Street, Santa Monica, California 90404

Dear Dr. Rice:

         Further to our recent telephone conversations, this letter serves to
confirm our agreement as follows:

         XOMA Corporation ("XOMA") acknowledges that UroGenesys, Inc.
("UroGenesys") will be entering into a 36 month (with 36 month option) lease
agreement with the Gomez Family Trust in respect of the above referenced
properties, previously subject to a STANDARD INDUSTRIAL LEASE - NET (the
"Lease") dated June 22, 1992 in favor of XOMA. XOMA agrees that its obligations
in terms of Paragraph 7.2 (as detailed below) of the Lease, shall survive
through the term of the aforementioned UG' obligation to surrender the premises,
excluding all items purchased from XOMA, at the end of the lease term in the
same condition as when received by UG, ordinary wear and tear excepted, clean
and free of debris. In addition, XOMA agrees to indemnify and defend UG against
all claims by the Gomez Family Trust with respect to Paragraph 7.4(c) of the UG
lease agreement except for any claims that result from a violation by UG of the
proviso in the second sentence of this paragraph.

         "7.2 Surrender. On the last day of the term hereof, or on any sooner
termination, Lessee shall surrender the premises to Lessor in the same condition
as when received, ordinary wear and tear excepted, clean and free of debris.
Lessee shall repair any damage to the premises occasioned by the installation or
removal of Lessee's trade fixtures, furnishings and equipment. Notwithstanding
anything to the contrary otherwise stated in this Lease, Lessee shall leave the
air lines, power panels, electrical distribution systems, lighting fixtures,
space heaters, air conditioning, plumbing and fencing on the premises in good
operating condition."

                             Yours truly,

                             /s/W. Courtney McGregor
                                 Vice President,
                                Technical Development and
                                Santa Monica Operations

We agree to the above terms and conditions.

UroGenesys, Inc.

/s/Donald B. Rice
Donald B. Rice
President and CEO
Date:  1/20/97


<PAGE>


               (LOGO) AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION
            STANDARD INDUSTRIAL/COMMERCIAL SINGLE-TENANT LEASE - NET
                (DO NOT USE THIS FORM FOR MULTI-TENANT BUILDINGS)

1.       Basic Provisions ("Basic Provisions")

     1.1 Parties: This Lease ("Lease"), dated for reference purposes only,
January 20, 1997, is made by and between Richard B. Gomez, Josephine L. Gomez,
TTEE U/A/D 10-31/1990 FBO Gomez Family Trust ("Lessor") and Uro Genesys, Inc., a
California corporation ("Lessee"), (collectively the "Parties," or individually
a "Party").

     1.2 Premises: That certain real property, including all improvements
therein or to be provided by Lessor under the terms of this Lease, and commonly
known as 1701 Colorado and 1553 17th St., Santa Monica, CA 90404 located in the
County of Los Angeles, State of California and generally described as Two
separate adjacent brick buildings consisting of approximately 10,000 sq. ft.,
with a total of 18 cars of parking area.

     1.3 Term: 3 years and months ("Original Term") commencing March 1, 1997
("Commencement Date") and ending ("Expiration Date"). (See also Paragraph 3)

     1.4 Early Possession: upon vacating of existing tenant ("Early Possession
Date"). (See also Paragraphs 3.2 and 3.3)

     1.5 Base Rent: $11,500 per month ("Base Rent"), payable on the first day of
each month commencing March 1, 1997. (See also Paragraph 4)

     1.6 Base Rent Paid Upon Execution: $11,500 as Base Rent for the period
March 1 through March 31, 1997.

     1.7 Security Deposit: $11,500 ("Security Deposit"). (See also Paragraph 5)

     1.8 Agreed Use: Bio-tech laboratory, general office or related lawful
biomedical development uses. (See also Paragraph 6) 

     1.9 Insuring Party: Lessee is the "Insuring Party" unless otherwise stated
herein. (See also Paragraph 8)

         1.10  Real Estate Brokers:  (See also Paragraph 15)
                  (a) Representation: The following real estate brokers
(collectively, the "Brokers") and brokerage relationships exist in this
transaction (check applicable boxes): (checked box) CB Commercial, Robert P.
Dubbins represents both Lessor and Lessee ("Dual Agency").
                  (b) Payment to Brokers: Upon execution and delivery of this
Lease by both Parties, Lessor shall pay to the Broker the fee agreed to in their
separate written agreement (of if there is no such agreement, the sum of
(blank)% of the total Base Rent for the brokerage services rendered by said
Broker). Lessee shall have no commission obligation.

         1.11 Guarantor. The obligations of the Lessee under this Lease are to
be guaranteed by N/A ("Guarantor"). (See also Paragraph 37)

         1.12 Addenda and Exhibits. Attached hereto is an Addendum or Addenda
consisting of Paragraphs 50 through 59 and Exhibits A, all of which constitute a
part of this Lease.

2.       Premises

         2.1 Letting. Lessor hereby leases to Lessee, and Lessee hereby leases
from Lessor, the Premises, for the term, at the rental, and upon all of the
terms, covenants and conditions set forth in this Lease. Unless otherwise
provided herein, any statement of size set forth in this Lease, or that may have
been used in calculating rental, is an approximation which the Parties agree is
reasonable and the rental based thereon is not subject to revision whether or
not the actual size is more or less.

         2.2 Condition. Lessor shall deliver the Premises to Lessee broom clean
and free of debris on the Commencement Date or the Early Possession Date,
whichever first occurs ("Start Date"), and, so long as the required service
contracts described in Paragraph 7.1(b) below are obtained by Lessee within
thirty (30) days following the Start Date, warrants that the exterior roof,
existing electrical, plumbing, fire sprinkler, lighting, heating, ventilating
and air conditioning systems ("HVAC"), loading doors, if any, and all other such
elements in the Premises, other than those constructed by Lessee, shall be in
good operating condition on said date and that the structural elements of the
roof, bearing walls, and foundation of any buildings on the Premises (the
"Building") shall be free of material defects. If a non-compliance with said
warranty exists as of the Start Date, Lessor shall, as Lessor's sole obligation
with respect to such matter, except as otherwise provided in this Lease,
promptly after receipt of written notice from Lessee setting forth with
specificity the nature and extent of such non-compliance, rectify the same at
Lessor's expense. If, after the Start Date, Lessee does not give Lessor written
notice of any non-compliance with this warranty within (i) one year as to the
surface of the roof and the structural portion of the roof foundations and
bearing walls, (ii) six (6) months as to the HVAC systems (iii) one hundred
twenty (120) days as to the remaining systems and other elements of the
Building, correction of such non-compliance shall be the obligation of Lessee at
Lessee's sole cost and expense.

         2.3 Compliance. Lessor warrants that the improvements on the Premises
comply with all applicable laws, covenants or restrictions of record, building
codes, regulations and ordinances ("Applicable Requirements") in effect on the
Start Date. Said warranty does not apply to the use to which Lessee will put the
Premises or to any Alterations or Utility Installations (as defined in Paragraph
7.3(a)) made or to be made by Lessee. NOTE: Lessee is responsible for
determining whether or not the zoning is appropriate for Lessee's intended use,
and acknowledges that past uses of the Premises may no longer be allowed. If the
Premises do not comply with said warranty, lessor shall, except as otherwise
provided, promptly after receipt of written notice from Lessee setting forth
with specificity the nature and extent of such non-compliance, rectify the same
at Lessor's expense. If Lessee does not give Lessor written notice of a
non-compliance with this warranty within six (6) months following the Start
Date, correction of that non-compliance shall be the obligation of Lessee at
Lessee's sole cost and expense. If the Applicable Requirements are hereafter
changed (as opposed to being in existence at the Start Date, which is addressed
in Paragraph 6.2(e) below) so as to require during the term of this Lease the
construction of an addition to or an alteration of the Building, the remediation
of any Hazardous Substance, or the reinforcement or other physical modification
of the Building ("Capital Expenditure"), Lessor and Lessee shall allocate the
cost of such work as follows:

                           PAGE 1                   Initials /s/RBG /s/DBR
<PAGE>
                  (a) Subject to Paragraph 2.3(c) below, if such Capital
Expenditures are required as a result of the specific and unique use of the
Premises by Lessee as compared with uses by tenants in general, Lessee shall be
fully responsible for the cost thereof, provided, however, that if such Capital
Expenditure is required during the last two (2) years of this Lease and the cost
thereof exceeds six (6) months' Base Rent, Lessee may instead terminate this
Lease unless Lessor notifies Lessee, in writing, within ten (10) days after
receipt of Lessee's termination notice that Lessor has elected to pay the
difference between the actual cost thereof and the amount equal to six (6)
months' Base Rent. If Lessee elects termination, Lessee shall immediately cease
the use of the Premises which requires such Capital Expenditure and deliver to
Lessor written notice specifying a termination date at least ninety (90) days
thereafter. Such termination date shall, however, in no event be earlier than
the last day that Lessee could legally utilize the Premises without commencing
such Capital Expenditure.
                  (b) If such Capital Expenditure is not the result of the
specific and unique use of the Premises by Lessee (such as, governmentally
mandated seismic modifications), then Lessor and Lessee shall allocate the
obligation to pay for such costs pursuant to the provisions of Paragraph 7.1(c);
provided, however, that if such Capital Expenditure is required during the last
six (6) months of this Lease or if Lessor reasonably determines that it is not
economically feasible to pay its share thereof, Lessor shall have the option to
terminate this Lease upon ninety (90) days prior written notice to Lessee unless
Lessee notifies Lessor, in writing, within ten (10) days after receipt of
Lessor's termination notice that Lessee will pay for such Capital Expenditure.
If Lessor fails to tender its share of any such Capital Expenditure, Lessee may
advance such funds and deduct same, with Interest, from Rent until Lessor's
share of such costs have been fully paid. If Lessee is unable to finance
Lessor's share, or if the balance of the Rent due and payable for the remainder
of this Lease is not sufficient to fully reimburse Lessee on an offset basis,
Lessee shall have the right to terminate this Lease upon thirty (30) days
written notice to Lessor.
                  (c) Notwithstanding the above, the provisions concerning
Capital Expenditures are intended to apply only to non-voluntary, unexpected,
and new Applicable Requirements. If the Capital Expenditures are instead
triggered by Lessee as a result of an actual or proposed change in use, change
in intensity of use, or modification to the Premises then, and in that event,
Lessee shall be fully responsible for the cost thereof, and Lessee shall not
have any right to terminate this Lease.

         2.4 Acknowledgements. Lessee acknowledges that: (a) it has been advised
by Lessor and/or Brokers to satisfy itself with respect to the condition of the
Premises (including but not limited to the electrical, HVAC and fire sprinkler
systems, security, environmental aspects, and compliance with Applicable
Requirements), and their suitability for Lessee's intended use, (b) Lessee has
made such investigation as it deems necessary with reference to such matters and
assumes all responsibility therefor as the same relate to its occupancy of the
Premises, and (c) neither Lessor, Lessor's agents, nor any Broker has made any
oral or written representations or warranties with respect to said matters other
than as set forth in this Lease. In addition, Lessor acknowledges that: (a)
Broker has made no representations, promises or warranties concerning Lessee's
ability to honor the Lease or suitability to occupy the Premises, and (b) it is
Lessor's sole responsibility to investigate the financial capability and/or
suitability of all proposed tenants.

         2.5 Lessee as Prior Owner/Occupant. The warranties made by Lessor in
Paragraph 2 shall be of no force or effect if immediately prior to the Start
Date Lessee was the owner or occupant of the Premises. In such event, Lessee
shall be responsible for any necessary corrective work.

3.       Term

         3.1 Term. The Commencement Date, Expiration Date, and Original Term of
this Lease are as specified in Paragraph 1.3.

         3.2 Early Possession. If Lessee totally or partially occupies the
Premises prior to the Commencement Date, the obligation to pay Base Rent shall
be abated for the period of such early possession. All other terms of this Lease
(including but not limited to the obligations to pay Real Property Taxes and
insurance premiums and to maintain the Premises) shall, however, be in effect
during such period. Any such early possession shall not affect the Expiration
Date.

         3.3 Delay in Possession. Lessor agrees to use its best commercially
reasonable efforts to deliver possession of the Premises to Lessee by the
Commencement Date. If, despite said efforts, Lessor is unable to deliver
possession as agreed, Lessor shall not be subject to any liability therefor, nor
shall such failure affect the validity of this Lease. Lessee shall not, however,
be obligated to pay Rent or perform its other obligations until it receives
possession of the Premises. If possession is not delivered within sixty (60)
days after the Commencement Date, Lessee may, at its option, by notice in
writing within ten (10) days after the end of such sixty (60) day period, cancel
this Lease, in which event the Parties shall be discharged from all obligations
hereunder. If such written notice is not received by Lessor within said ten (10)
day period, Lessee's right to cancel shall terminate. Except as otherwise
provided, if possession is not tendered to Lessee when required and Lessee does
not terminate this Lease, as aforesaid, any period of rent abatement that Lessee
would otherwise have enjoyed under the terms hereof, but minus any days of delay
caused by the acts or omissions of Lessee. If possession of the Premises is not
delivered within four (4) months after the Commencement Date, this Lease shall
terminate unless other agreements are reached between Lessor and Lessee, in
writing.

         3.4 Lessee Compliance. Lessor shall not be required to tender
possession of the Premises to Lessee until Lessee complies with its obligation
to provide evidence of insurance (Paragraph 8.5). Pending delivery of such
evidence, Lessee shall be required to perform all of its obligations under this
Lease from and after the Start Date, including the payment of Rent,
notwithstanding Lessor's election to withhold possession pending receipt of such
evidence of insurance. Further, if Lessee is required to perform any other
conditions prior to or concurrent with the Start Date, the Start Date shall
occur but Lessor may elect to withhold possession until such conditions are
satisfied.

4.       Rent

         4.1 Rent Defined. All monetary obligations of Lessee to Lessor under
the terms of this Lease (except for the Security Deposit) are deemed to be rent
("Rent").

         4.2 Payment. Lessee shall cause payment of Rent to be received by
Lessor in lawful money of the United States, without offset or deduction, on or
before the day on which it is due. Rent for any period during the term hereof
which is for less than one (1) full calendar month shall be prorated based upon
the actual number of days of said month. Payment of Rent shall be made to Lessor
at its address stated herein or to such other persons or place as Lessor may
from time to time designate in writing. Acceptance of a payment which is less
than the amount then due shall not be a waiver of Lessor's rights to the balance
of such Rent, regardless of Lessor's endorsement of any check so stating.

5. Security Deposit. Lessee shall deposit with Lessor upon execution hereof the
Security Deposit as security for Lessee's faithful performance of its
obligations under this Lease. If Lessee fails to pay Rent, or otherwise Defaults
under this Lease, Lessor may use, apply or retain all or any portion of said
Security Deposit for the payment of any amount due Lessor or to reimburse or
compensate Lessor for any liability, expense, loss or damage which Lessor may
suffer or incur by reason thereof. If Lessor uses or applies all or any portion
of said Security Deposit, Lessee shall within ten (10) days after written
request therefor deposit monies with Lessor sufficient to restore said Security
Deposit to the full amount required by this Lease. If the Base Rent increases
during the term of this Lease, Lessee shall, upon written request from Lessor,
deposit additional moneys with Lessor so that the total amount of the Security
Deposit shall at all times bear the same proportion to the increased Base Rent
as the Initial Security Deposit bore to the initial Base Rent. Should the Agreed
Use be amended to accommodate a material change in the business of Lessee or to
accommodate a sublessee or assignee, Lessor shall have the right to increase the
Security Deposit to the extent necessary, in lessor's reasonable judgement, to
account for any increased wear and tear that the Premises may suffer as a result
thereof. If a change in control of Lessee occurs during this Lease and following
such change the financial condition of Lessee is, in Lessor's reasonable
judgment, significantly reduced, Lessee shall deposit such additional monies
with Lessor as shall be sufficient to cause the Security Deposit to be at a
commercially reasonable level based on said change in financial condition.
Lessor shall not be required to keep the Security Deposit separate from its
general accounts. Within fourteen (14) days after the expiration or termination
of this Lease, if Lessor elects to apply the Security Deposit only to unpaid
Rent, and otherwise within thirty (30) days after the Premises have been vacated
pursuant to Paragraph 7.4(c) below, Lessor shall return that portion of the
Security Deposit not used or applied by Lessor. No part of the Security Deposit
shall be considered to be held in trust, to bear interest, or to be prepayment
for any monies to be paid by Lessee under this Lease.

6.       Use.

         6.1 Use. Lessee shall use and occupy the Premises only for the Agreed
Use, or any other legal use which is reasonably comparable thereto, and for no
other purpose. Lessee shall not use or permit the use of the Premises in a
manner that is unlawful, creates damage, waste or a nuisance, or that disturbs
owners and/or occupants of, or causes damage to neighboring properties. Lessor
shall not unreasonably withhold

                   PAGE 2                                 Initials /s/RBG /s/DBR
<PAGE>
or delay its consent to any written request for a modification of the Agreed
Use, so long as the same will not impair the structural integrity of the
improvements on the Premises or the mechanical or electrical systems therein, is
not significantly more burdensome to the Premises. If Lessor elects to withhold
consent, Lessor shall within five (5) business days after such request give
written notification of same, which notice shall include an explanation of
Lessor's objections to the change in use.

         6.2      Hazardous Substances.
                  (a) Reportable Uses Require Consent. The term "Hazardous
Substance" as used in this Lease shall mean any product, substance or waste
whose presence, use, manufacture, disposal, transportation, or release, either
by itself or in combination with other materials expected to be on the Premises,
is either: (i) potentially injurious to the public health, safety or welfare,
the environment or the Premises, (ii) regulated or monitored by any governmental
authority, or (iii) a basis for potential liability of Lessor to any
governmental agency or third party under any applicable statute or common law
theory. Hazardous Substances shall include, but not be limited to, hydrocarbons,
petroleum, gasoline, and/or crude oil or any products, by-products or fractions
thereof. Lessee shall not engage in any activity in or on the Premises which
constitutes a Reportable Use of Hazardous Substances without the express prior
written consent of Lessor and timely compliance (as Lessee's expense) with all
Applicable Requirements. "Reportable Use" shall mean (i) the installation or use
of any above or below ground storage tank, (ii) the generation, possession,
storage, use, transportation, or disposal of a Hazardous Substance that requires
a permit from, or with respect to which a report, notice, registration or
business plan is required to be filed with, any governmental authority, and/or
(iii) the presence at the Premises of a Hazardous Substance with respect to
which any Applicable Requirements requires that a notice be given to persons
entering or occupying the Premises or neighboring properties. Notwithstanding
the foregoing, Lessee may use any ordinary and customary materials reasonably
required to be used in the normal course of the Agreed Use, so long as such use
is in compliance with all Applicable Requirements, and does not expose the
Premises or neighboring property to any meaningful risk of contamination or
damage or expose Lessor to any liability therefor. In addition, Lessor may
condition its consent to any Reportable Use upon receiving such additional
assurances as Lessor reasonably deems necessary to protect itself, the public,
the Premises and/or the environment against damage, contamination, injury and/or
liability, including, but not limited to, the installation (and removal on or
before Lease expiration or termination) of protective modifications (such as
concrete encasements) and/or increasing the Security Deposit.
                  (b) Duty to Inform Lessor. If Lessee knows, or has reasonable
cause to believe, that a Hazardous Substance has come to be located in, on,
under or about the Premises, other than as previously consented to by Lessor,
Lessee shall immediately give written notice of such fact to Lessor, and provide
Lessor with a copy of any report, notice, claim or other documentation which it
has concerning the presence of such Hazardous Substance.
                  (c) Lessee Remediation. Lessee shall not cause or permit any
Hazardous Substance to be spilled or released in, on, under, or about the
Premises (including through the plumbing or sanitary sewer system) and shall
promptly, at Lessee's expense, take all investigatory and/or remedial action
reasonably recommended, whether or not formally ordered or required, for the
cleanup of any contamination of, and for the maintenance, security and/or
monitoring of the Premises or neighboring properties, that was caused or
materially contributed to by Lessee, or pertaining to or involving any Hazardous
Substance brought onto the Premises during the term of this Lease, by or for
Lessee, or any third party.
                  (d) Lessee Indemnification. Lessee shall indemnify, defend and
hold Lessor, its agents, employees, lenders and ground lessor, if any, harmless
from and against any and all loss of rents and/or damages, liabilities,
judgments, claims, expenses, penalties, and attorneys' and consultants' fees
(together, "Damages") arising out of or involving any Hazardous Substance
brought onto the Premises by or for Lessee, or any third party (provided,
however, that Lessee shall have no liability under this Lease with respect to
underground migration of any Hazardous Substance under the Premises from
adjacent properties). Lessee's obligations shall include, but not be limited to,
the effects of any contamination or injury to person, property or the
environment (together, "Effects") created or suffered by Lessee, and the cost of
investigation, removal, remediation, restoration and/or abatement and shall
survive the expiration or termination of this Lease. No termination,
cancellation or release agreement entered into by Lessor and Lessee shall
release Lessee from its obligations under this lease with respect to Hazardous
Substances, unless specifically so agreed by Lessor in writing at the time of
such agreement.
                  (e) Lessor Indemnification. Lessor and its successors and
assigns shall indemnify, defend, reimburse and hold Lessee, its employees and
lenders, harmless from and against any and all Damages arising out of or
involving the presence, migration or discharge of Hazardous Substances on or
affecting the Premises prior to the Start Date or which are caused by the
negligence, or other acts of Lessor, its agents or employees. Lessor's
obligations shall include, but not be limited to, the Effects, the cost of
investigation, removal, remediation, restoration, and/or abatement, and shall
survive the expiration or termination of this Lease.
                  (f) Investigations and Remediations. Lessor shall retain the
responsibility and pay for any investigations or remediation measures required
by governmental entities having jurisdiction with respect to the existence of
Hazardous Substances on the Premises prior to the Start Date. Lessee shall
cooperate fully in any such activities at the request of Lessor, including
allowing Lessor and Lessor's agents to have reasonable access to the Premises at
reasonable times in order to carry out Lessor's investigative and remedial
responsibilities.
                  (g) Landlord Termination Option. If a Hazardous Substance
Condition occurs during the term of this Lease, unless Lessee is legally
responsible therefor (in which case Lessee shall make the investigation and
remediation thereof required by the Applicable Requirements and this Lease shall
continue in full force and effect, but subject to Lessor's rights under
Paragraph 6.2(d) and Paragraph 13), Lessor may, at Lessor's option, either (i)
investigate and remediate such Hazardous Substance Condition, if required, as
soon as reasonably possible at Lessor's expense, in which event this Lease shall
continue in full force and effect, or (ii) if the estimated cost to remediate
such condition exceeds twelve (12) times the then monthly Base Rent or $100,000,
whichever is greater, give written notice to Lessee, within thirty (30) days
after receipt by Lessor of knowledge of the occurrence of such Hazardous
Substance Condition, of Lessor's desire to terminate this Lease as of the date
sixty (60) days following the date of such notice. In the event Lessor elects to
give a termination notice, Lessee may, within ten (10) days thereafter, give
written notice to Lessor of Lessee's commitment to pay the amount by which the
cost of the remediation of such Hazardous Substance Condition exceeds an amount
equal to twelve (12) times the then monthly Base Rent or $100,000, whichever is
greater. Lessee shall provide Lessor with said funds or satisfactory assurance
thereof within thirty (30) days following such commitment. In such event, this
Lease shall continue in full force and effect, and Lessor shall proceed to make
such remediation as soon as reasonably possible after the required funds are
available. If Lessee does not give such notice and provide the required funds or
assurance thereof within the time provided, this Lease shall terminate as of the
date specified in Lessor's notice of termination.

         6.3 Lessee's Compliance with Applicable Requirements. Except as
otherwise provided in this Lease, Lessee shall, at Lessee's sole expense, fully,
diligently and in a timely manner, materially comply with all Applicable
Requirements, the requirements of any applicable fire insurance underwriter or
rating bureau, and the recommendations of Lessor's engineers and/or consultants
which relate in any manner to the Premises, without regard to whether said
requirements are now in effect or become effective after the Start Date. Lessee
shall within ten (10) days after receipt of Lessor's written request, provide
Lessor with copies of all permits and other documents and other information
evidencing Lessee's compliance with any Applicable Requirements specified by
Lessor, and shall immediately upon receipt, notify Lessor in writing (with
copies of any documents involved) of any threatened or actual claim, notice,
citation, warning, complaint or report pertaining to or involving the failure of
Lessee or the Premises to comply with any Applicable Requirements.

         6.4 Inspection; Compliance. Lessor and Lessor's Lender and consultants
shall have the right to enter into the Premises at any time, in the case of an
emergency, and otherwise at reasonable times, for the purpose of inspecting the
condition of the Premises and for verifying compliance by Lessee with this
Lease. The cost of any such inspections shall be paid by the Lessor, unless a
violation of Applicable Requirements, or a contamination is found to exist or be
imminent, or the inspection is requested or ordered by a governmental authority.
In such case, Lessee shall upon request reimburse Lessor for the cost of such
inspections, so long as such inspection is reasonably related to the violation
or contamination.

7.   Maintenance; Repairs, Utility Installations; Trade Fixtures and
     Alterations.

         7.1      Lessee's Obligations.
                  (a) In General. Subject to the provisions of Paragraph 2.2
(Condition), 2.3 (Compliance), 6.3 (Lessee's Compliance with Applicable
Requirements), 7.2 (Lessor's Obligations), 9 (Damage or Destruction), and 14
(Condemnation), Lessee shall, at Lessee's sole expense, keep

                PAGE 3                                  Initials /s/RBG /s/DBR
<PAGE>
the Premises, Utility Installations, and Alterations in good order, condition
and repair (whether or not the portion of the Premises requiring repairs, or the
means of repairing the same, are reasonable or readily accessible to Lessee, and
whether or not the need for such repairs occurs as a result of Lessee's use, any
prior use, the elements or the age of such portion of the Premises), including,
but not limited to, all equipment or facilities, such as plumbing, HVAC,
electrical, lighting facilities, boilers, pressure vessels, fire protection
system, fixtures, walls (interior and exterior), foundations, ceilings, roofs,
floors, windows, doors, plate glass, skylights, landscaping, driveways, parking
lots, fences, retaining walls, signs, sidewalks and parkways located in, on, or
adjacent to the Premises. Lessee, in keeping the Premises in good order,
condition and repair, shall exercise and perform good maintenance practices,
specifically including the procurement and maintenance of the service contracts
required by Paragraph 7.1(b) below. Lessee's obligations shall include
restorations (including restoration required by Santa Monica City Ordinance),
replacements or renewals when necessary to keep the Premises and all
improvements thereon or a part thereof in good order, condition and state of
repair. Lessee shall, during the term of this Lease, keep the exterior
appearance of the Building in a first-class condition consistent with the
exterior appearance of other similar facilities of comparable age and size in
the vicinity, including, when necessary, the exterior repainting of the
Building.
                  (b)  deleted.
                  (c) Replacement. Subject to Lessee's indemnification of Lessor
as set forth in Paragraph 8.7 below, and without relieving Lessee of liability
resulting from Lessee's failure to exercise and perform good maintenance
practices, if the Basic Elements described in Paragraph 7.1(b) cannot be
repaired other than at a cost which is in excess of 50% of the cost of replacing
such Basic Elements, then such Basic Elements shall be replaced by Lessor, and
the cost thereof shall be prorated between the Parties and Lessee shall only be
obligated to pay, each month during the remainder of the term of this Lease, on
the date on which Base Rent is due, an amount equal to the product of
multiplying the cost of such replacement by a fraction, the numerator of which
is one, and the denominator of which is the number of months of the useful life
of such replacement as such useful life is specified pursuant to Federal income
tax regulations or guidelines for depreciation thereof (including interest on
the unamortized balance as is then commercially reasonable in the judgment of
Lessor's accountants), with Lessee reserving the right to prepay its obligation
at any time.

         7.2 Lessor's Obligations. Subject to the provisions of Paragraphs 2.2
(Condition), 2.3 (Compliance), 9 (Damage and Destruction) and 14 (Condemnation),
it is intended by the Parties hereto that Lessor have no obligation, in any
manner whatsoever, to repair and maintain the Premises, or the equipment
therein, all of which obligations of the Parties as to maintenance and repair of
the Premises, and they expressly waive the benefit of any statute now or
hereafter in effect to the extent it is inconsistent with the terms of this
Lease.

         7.3  Utility Installations; Trade Fixtures; Alterations.
                  (a) Definitions; Consent Required. The term "Utility
Installations" refers to all floor and window coverings, air lines, power
panels, electrical distribution, security and fire protection systems,
communication systems, lighting fixtures, HVAC equipment, plumbing, and fencing
in or on the Premises. The term "Trade Fixtures" shall mean Lessee's machinery
and equipment that can be removed without doing material damage to the Premises.
The term "Alterations" shall mean any modification of the improvements, other
than Utility Installations or Trade Fixtures, whether by addition or deletion.
"Lessee Owned Alterations and/or Utility Installations" are defined as
Alterations and/or Utility Installations made by Lessee that are not yet owned
by Lessor pursuant to Paragraph 7.4(a). Lessee shall not make any alterations of
Utility Installations to the Premises without Lessor's prior written consent.
Lessee may, however, make non-structural Utility Installations to the interior
of the Premises (excluding the roof) without such consent but upon notice to
Lessor, as long as they are not visible from the outside, do not involve
puncturing, relocating or removing the roof or any existing walls, and the
cumulative cost thereof during this Lease as extended does not exceed $50,000 in
the aggregate or $10,000 in any one year.
                  (b) Consent. Any Alterations or Utility Installations that
Lessee shall desire to make and which require the consent of the Lessor shall be
presented to Lessor in written form with detailed plans. Consent shall be deemed
conditioned upon Lessee's (i) acquiring all applicable governmental permits,
(ii) furnishing Lessor with copies of both the permits and the plans and
specifications prior to commencement of the work, and (iii) compliance with all
conditions of said permits and other Applicable Requirements in a prompt and
expeditious manner. Any alterations or Utility Installations shall be performed
in a workmanlike manner with good and sufficient materials. Lessee shall
promptly upon completion furnish Lessor with as-built plans and specifications.
For work which costs an amount equal to the greater of one month's Base Rent, or
$10,000, Lessor may condition its consent upon Lessee providing a lien and
completion bond in an amount equal to one and one-half times the estimated cost
of such Alteration or Utility Installation and/or upon Lessee's posting an
additional Security Deposit with Lessor.
                  (c) Indemnification. Lessee shall pay, when due, all claims
for labor or materials furnished or alleged to have been furnished to or for
Lessee at or for use on the Premises, which claims are or may be secured by any
mechanic's or materialmen's lien against the Premises or any interest therein.
Lessee shall give Lessor not less than ten (10) days' notice prior to the
commencement of any work in, on or about the Premises, and Lessor shall have the
right to post notices of non-responsibility. If Lessee shall contest the
validity of any such lien, claim or demand, then Lessee shall, at its sole
expense defend and protect itself, Lessor and the Premises against the same and
shall pay and satisfy any such adverse judgment that may be rendered thereon
before the enforcement thereof. If Lessor shall require, Lessee shall furnish a
surety bond in an amount equal to one and one-half times the amount of such
contested lien, claim or demand, indemnifying Lessor against liability for the
same. If Lessor elects to participate in any such action, Lessee shall pay
Lessor's attorneys' fees and costs.

         7.4  Ownership; Removal; Surrender; and Restoration.
                  (a) Ownership. Subject to Lessor's right to require removal or
elect ownership as hereinafter provided, all Alterations and Utility
Installations made by Lessee shall be the property of Lessee, but considered a
part of the Premises. Lessor may, at any time, elect in writing to be the owner
of all or any specified part of the Lessee Owned Alterations and Utility
Installations. Unless otherwise instructed per Paragraph 7.4(b) hereof, all
Lessee Owned Alterations and Utility Installations shall, at the expiration or
termination of this Lease, become the property of Lessor and be surrendered by
Lessee with the Premises.
                  (b) Removal. By delivery to Lessee of written notice from
Lessor not later than ninety (90) days prior to the end of the term of this
Lease, Lessor may require that any or all Lessee Owned Alterations or Utility
Installations be removed by the expiration or termination of this Lease. Lessor
may require the removal at any time of all or any part of any Lessee Owned
Alterations or Utility Installations made without the required consent.
                  (c) Surrender/Restoration. Lessee shall surrender the Premises
by the Expiration Date or any earlier termination date, with all of the
improvements, parts and surfaces thereof broom clean and free of debris, and in
good operating order, condition and state of repair, ordinary wear and tear
excepted. "Ordinary wear and tear" shall not include any damage or deterioration
that would have been prevented by good maintenance practice. Lessee shall repair
any damage occasioned by the installation, maintenance or removal of Trade
Fixtures, furnishings, and equipment as well as the removal of any storage tank
installed by or for Lessee and the removal, replacement, or remediations of any
soil, material, or groundwater contaminated by Lessee. Trade Fixtures shall
remain the property of Lessee and shall be removed by Lessee. The failure by
Lessee to timely vacate the Premises pursuant to this Paragraph 7.4(c) without
the express written consent of Lessor shall constitute a holdover under the
provisions of Paragraph 26 below.

8.       Insurance; Indemnity.

         8.1. Payment For Insurance. Lessee shall pay for all insurance required
under Paragraph 8 except to the extent of the cost attributable to liability
insurance carried by Lessor under Paragraph 8.2(b) in excess of $2,000,000 per
occurrence. Premiums for policy periods commencing prior to or extending beyond
the Lease term shall be prorated to correspond to the Lease term. Payment shall
be made by Lessee to Lessor within ten (10) days following receipt of an
invoice.

         8.2  Liability Insurance.
                  (a) Carried by Lessee. Lessee shall obtain and keep in force a
Commercial General Liability Policy of Insurance protecting Lessee

               PAGE 4                                 Initials /s/RBG /s/DBR
<PAGE>
                  (b) Carried by Lessor. Lessor shall maintain liability
insurance as described in Paragraph 8.2(a), in addition to, and not in lieu of,
the insurance required to be maintained by Lessee. Lessee shall not be named as
an additional insured therein.

         8.3  Property Insurance - Building, Improvements and Rental Value.
                  (a) Building and Improvements. The Insuring party shall obtain
and keep in force a policy or policies in the name of Lessor, with and to any
Lender insuring loss or damage to the Premises. The amount of such insurance
shall be equal to the full replacement cost of the Premises, as the same shall
exist from time to time, or the amount required by an Lenders, but in no event
more than the commercially reasonable and available insurable value thereof. If
Lessor is the Insuring Party, however, Lessee Owned Alterations and Utility
Installation, Trade Fixtures, and Lessee's personal property shall be insured by
Lessee under Paragraph 8.4 rather than by Lessor. If the coverage is available
and commercially appropriate, such policy or policies shall insure against all
risks of direct physical loss or damage (except the peril of flood and/or
earthquake), including coverage for debris removal and the enforcement of any
Applicable Requirements requiring the upgrading, demolition, reconstruction or
replacement of any portion of the Premises as the result of a covered loss. Said
policy or policies shall also contain an agreed valuation provision in lieu of
any coinsurance clause, waiver of subrogation, and inflation guard protection
causing an increase in the annual property insurance coverage amount by a factor
of not less than the adjusted U.S. Department of Labor Consumer Price Index for
all Urban Consumers for the city nearest to where the Premises are located. If
such insurance coverage has a deductible clause, the deductible amount shall not
exceed $50,000 per occurrence and Lessee shall be liable for such deductible
amount in the event of an Insured Loss.
                  (b) Rental Value. The Insuring Party shall obtain and keep in
force a policy or policies in the name of Lessor with loss payable to Lessor and
any Lender, insuring the loss of the full Rent for one (1) year. Said insurance
shall provide that in the event the Lease is terminated by reason of an insured
loss, the period of indemnity for such coverage shall be extended beyond the
date of the completion of repairs or replacement of the Premises, to provide for
one full year's loss of Rent from the date of any such loss. Said insurance
shall contain an agreed valuation provision in lieu of any coinsurance clause,
and the amount of coverage shall be adjusted annually to reflect the projected
Rent otherwise payable by Lessee, for the next twelve (12) month period. Lessee
shall be liable for any deductible amount in the event of such loss.
                  (c) Adjacent Premises. If the Premises are part of a larger
building, or of a group of buildings owned by Lessor which are adjacent to the
Premises, the Lessee shall pay for any increase in the premiums for the property
insurance of such building or buildings if said increase is caused by Lessee's
acts, omissions, use or occupancy of the Premises.

         8.4  Lessee's Property/Business Interruption Insurance.
                  (a) Property Damage. Lessee shall obtain and maintain
insurance coverage on all of Lessee's personal property, Trade fixtures, and
Lessee Owned Alterations and Utility Installations. Such insurance shall be full
replacement cost coverage with a deductible of not to exceed $25,000 per
occurrence. The proceeds from any such insurance shall be used by Lessee for the
replacement of personal property, Trade Fixtures and Lessee Owned Alterations
and Utility Installations. Lessee shall provide Lessor with written evidence
that such insurance is in force.
                  (b) Business Interruption. If reasonably available, and if
Lessor requests Lessee to do so in writing, Lessee shall obtain and maintain
loss of income and extra expense insurance in amounts as will reimburse Lessee
for direct or indirect loss of earnings attributable to all perils commonly
insured against by prudent lessees in the business of Lessee or attributable to
prevention of access to the Premises as a result of such perils.
                  (c) No Representation of Adequate Coverage. Lessor makes no
representation that the limits or forms of coverage of insurance specified
herein are adequate to cover Lessee's property, business operations or
obligations under this Lease.

         8.5 Insurance Policies. Insurance required herein shall be by companies
duly licensed or admitted to transact business in the state where the Premises
are located, and maintaining during the policy term a "General Policyholders
Rating" of at least B+, V, as set forth in the most current issue of "Best's
Insurance Guide", or such other rating as may be required by a Lender. Lessee
shall not do or permit to be done anything which invalidates the required
insurance policies. Lessee shall, prior to the Start Date, deliver to Lessor
certified copies of policies of such insurance or certificates evidencing the
existence and amounts of the required insurance. No such policy shall be
cancelable or subject to modification except after thirty (30) days prior
written notice to Lessor. Lessee shall, at least thirty (30) days prior to the
expiration of such policies, furnish Lessor with evidence of renewals or
"insurance binders" evidencing renewal thereof, or Lessor may order such
insurance and charge the costs thereof to Lessee, which amount shall be payable
by lessee to Lessor upon demand. Such policies shall be for a term of at least
one year, or the length of the remaining term of this Lease, whichever is less.
If either Party shall fail to procure and maintain the insurance required to be
carried by it, the other Party may, but shall not be required to, procure and
maintain the same.

         8.6 Waiver of Subrogation. Without affecting any other rights or
remedies, Lessee and Lessor each hereby release and relieve the other, and waive
their entire right to recover damages against the other, for loss of or damage
to its property arising out of or incident to the perils required to be insured
against herein. The effect of such releases and waivers is not limited by the
amount of insurance carried or required, or by any deductibles applicable
hereto. The Parties agree to have their respective property damage insurance
carriers waive any right to subrogation that such companies may have against
Lessor or Lessee, as the case may be, so long as the insurance is not
invalidated thereby.

         8.7 Indemnity. Except for Lessor's sole negligence, Lessee shall
indemnify, protect, defend and hold harmless the Premises, Lessor and its
agents, Lessor's master or ground lessor, partners and Lenders, from and against
any and all claims, loss of rents and/or damages, liens, judgments, penalties,
attorneys' and consultants; fees, expenses and/or liabilities arising out of,
involving, or in connection with, the use and/or occupancy of the Premises by
Lessee. If any action or proceeding is brought against Lessor by reason of any
of the foregoing matters, Lessee shall upon notice defend the same at Lessee's
expense by counsel satisfactory to Lessor and Lessor shall cooperate with Lessee
in such defense. Lessor need not have first paid any such claim in order to be
defended or indemnified.

         8.8 Exemption of Lessor from Liability. Lessor shall not be liable for
injury to the person or goods, wares, merchandise or other property of Lessee,
Lessee's employees, contractors, invitees, customers, or any other person in or
about the Premises, whether such damage or injury is caused by or results from
fire, steam, electricity, gas, water or rain, or from the breakage, leakage,
obstruction or other defects of pipes, fire sprinklers, wires, appliances,
plumbing, HVAC or lighting fixtures, or from any other cause, whether the said
damage or injury results from conditions arising upon the Premises or upon other
portions of the Building of which the Premises are a part, or from other sources
or places. Lessor shall not be liable for any damages arising from any act or
neglect of any other tenant of Lessor. Notwithstanding Lessor's negligence or
breach of this Lease, Lessor shall under no circumstances be liable for injury
to Lessee's business or for any loss of income or profit therefrom.

9.       Damage or Destruction.

         9.1 Definitions.
                  (a) "Premises Partial Damage" shall herein mean damage or
destruction to the improvements on the Premises, other than Lessee Owned
Alternations and Utility Installations, which can be repaired in six (6) months
or less from the date of the damage or destruction. Lessor shall notify Lessee
in writing thirty (30) days from the date of the damage or destruction as to
whether or not the damage is Partial or Total.
                  (b) "Premises Total Destruction" shall mean damage or
destruction to improvements on the Premises, other than Lessee Owned Alterations
and Utility Installations, which cannot reasonably be repaired in six (6) months
or less from the date of the damage or destruction. Lessor shall notify Lessee
in writing thirty (30) days from the date of the damage or destruction as to
whether or not the damage is Partial or Total.

               PAGE 5                            Initials ./s/RBG /s/DBR
<PAGE>
                  (c) "Insured Loss" shall herein mean damage or destruction to
improvements on the Premises, other than Lessee Owned Alterations and Utility
Installations and Trade Fixtures, which was caused by an event required to be
covered by the insurance described in paragraph 8.3(a), irrespective of any
deductible amounts of coverage limits involved.
                  (d) "Replacement Cost" shall mean the cost to repair or
rebuild the improvements owned by Lessor at the time of the occurrence to their
condition existing immediately prior thereto, including demolition, debris
removal and upgrading required by the operation of Applicable Requirements, and
without deduction for depreciation.
                  (e) "Hazardous Substance Condition" shall bean the occurrence
of discovery of a condition involving the presence of, or a contamination by, a
Hazardous Substance as defined in paragraph 6.2(a), in, on, or under the
Premises.

         9.2 Partial Damage - Insured Loss. If a Premises partial Damage that is
an Insured Loss occurs, then Lessor shall, at Lessee's, at Lessor's expense,
repair such damage, (but not Lessee's Trade Fixtures or Lessee Owned Alterations
and Utility Installations) as soon as reasonably possible and this Lease shall
continue in full force and effect; provided, however, that Lessee shall, at
Lessor's election, make the repair of any damage or destruction the total cost
to repair of which is $10,000 or less, and, in such event, Lessor shall make any
applicable insurance proceeds available to Lessee on a reasonable basis for that
purpose. Notwithstanding the foregoing, if the required insurance was not in
force or the insurance proceeds are not sufficient to effect such repair, the
Insuring Party shall promptly contribute the shortage in proceeds (except as to
the deductible which is Lessee's responsibility) as and when required to
complete said repairs. In the event, however, such shortage was due to the fact
that, by reason of the unique nature of the improvements, full replacement cost
insurance coverage was not commercially reasonable and available, Lessor shall
have no obligation to pay for the shortage in insurance proceeds or to fully
restore the unique aspects of the Premises unless Lessee provides Lessor with
the funds to cover same, or adequate assurance thereof, within ten (10) days
following receipt of written notice of such shortage and request therefor. If
Lessor receives said funds or adequate assurance therefor within said ten (10)
day period, the party responsible for making the repairs shall complete them as
soon as reasonably possible and this Lease shall remain in full force and
effect. If such funds or assurance are not received, Lessor may nevertheless
elect by written notice to Lessee within ten (10) days thereafter to: (i) make
such restoration and repair as is commercially reasonable with Lessor paying any
shortage in proceeds, in which case this Lease shall remain in full force and
effect, or have this Lease terminate thirty (30) days thereafter. Lessee shall
not be entitled to reimbursement of any funds contributed by Lessee to repair
any such damage or destruction. Premises Partial Damage due to flood or
earthquake shall be subject to Paragraph 9.3, notwithstanding that there may be
some insurance coverage, but the net proceeds of any such insurance shall be
made available for the repairs if made by either Party.

         9.3 Partial Damage - Uninsured Loss. If a Premises Partial Damage that
is not an Insured Loss occurs, unless caused by a negligent or willful act of
Lessee (in which event Lessee shall make the repairs at Lessee's expense),
Lessor may either: (i) repair such damage as soon as reasonably possible at
Lessor's expense, in which event this Lease shall continue in full force and
effect, or (ii) terminate this Lease by giving written notice to Lessee within
thirty (30) days after receipt by Lessor of knowledge of the occurrence of such
damage. Such termination shall be effective sixty (60 days following the date of
such notice. In the event Lessor elects to terminate this Lease, Lessee shall
have the right within ten (10) days after receipt of the termination notice to
give written notice to Lessor of Lessee's commitment to pay for the repair of
such damage, without reimbursement from Lessor. Lessee shall provide Lessor with
said funds or satisfactory assurance thereof within thirty (30) days after
making such commitment. In such event this Lease shall continue in full force
and effect, and Lessee shall proceed to make such repairs as soon as reasonably
possible after the required funds are available. If Lessee does not make the
required commitment, this Lease shall terminate as of the date specified in the
termination notice.

         9.4 Total Destruction. Notwithstanding any other provision hereof, if a
Premises total Destruction occurs, this Lease shall automatically terminate
sixty (60) days following such Destruction. If the damage or destruction was
caused by the gross negligence or willful misconduct of Lessee, Lessor shall
have the right to recover Lessor's damages from Lessee except as provided in
Paragraph 8.6.

         9.5 Damage Near End of Term. If any time during the last six (6) months
of this Lease there is damage for which the cost to repair exceeds one (1)
month's Base Rent, whether or not an Insurance Loss, Lessor may terminate this
Lease effective ninety (90) days following the date of occurrence of such damage
by giving a written termination notice to Lessee within thirty (30) days after
the date of occurrence of such damage. Notwithstanding the foregoing, if Lessee
at that time has an exercisable option to extend this Lease or to purchase the
Premises, then Lessee may preserve this Lease by, (a) exercising such options
and (b) providing Lessor with any shortage in insurance proceeds (or adequate
assurance therefor) needed to make the repairs on or before the earlier of (i)
the date which is ten days after Lessee's receipt of Lessor's written notice
purporting to terminate this Lease, or (ii) the day prior to the date upon which
such option expires. If Lessee duly exercises such option during such period and
provides Lessor with funds (or adequate assurance thereof) to cover any shortage
in insurance proceeds, Lessor shall, at Lessor's commercially reasonable
expense, repair such damage as soon as reasonably possible and this Lease shall
continue in full force and effect. If Lessee fails to exercise such option and
provide such funds or assurance during such period, then this Lease shall
terminate on the date specified in the termination notice and Lessee's option
shall be extinguished.

         9.6  Abatement of Rent: Lessee's Remedies
                  (a) Abatement. In the even of Premises Partial Damage or
Premises Total Destruction or a Hazardous Substance Condition for which Lessee
is not responsible under this Lease, the Rent payable by Lessee for the period
required for the repair, remediation or restorations of such damage shall be
abated in proportion to the degree to which Lessee's use of the Premises is
impaired, but not to exceed the proceeds received from the Rental Value
insurance. All other obligations of Lessee hereunder shall be performed by
Lessee, and Lessor shall have no liability for any such damage, destruction,
remediation, repair or restoration except as provided herein.
                  (b) Remedies. If Lessor shall be obligated to repair or
restore the Premises and does not commence, in a substantial and meaningful way,
such repair or restoration within ninety (90) days after such obligation shall
accrue, lessee may, at any time prior to the commencement of such repair or
restoration, give written notice to Lessor and to any Lenders of which Lessee
has actual notice, of Lessee's election to terminate this lease on a date not
less than sixty (60) days following the giving of such notice. If Lessee give
such notice and such repair or restoration is not commenced within thirty (30)
days thereafter, this Lease shall terminate as of the date specified in said
notice. If the repair or restoration is commenced within said thirty (30) days,
this Lease shall continue in full force and effect. "Commence' shall mean either
the unconditional authorization of the preparation of the required plans, or the
beginning of the actual work on the Premises, whichever first occurs.

         9.7 Termination-Advance Payments. Upon termination of this Lease
pursuant to Paragraph 6.2(g) or Paragraph 9, an equitable adjustment shall be
made concerning advance Base Rent and any other advance payments made by Lessee
to Lessor. Lessor shall, in addition, return to Lessee so much of Lessee's
Security Deposit as has not been, or in not then required to be, used by Lessor.

         9.8 Waive Statutes. Lessor and Less agree that the terms of this Lease
shall govern the effect of any damage to or destruction of the Premises with
respect to the termination of this Lease and hereby waive the provisions of any
present or future statue to the extent inconsistent herewith.

         10.      Real Property Taxes.

         10.1 Definition of "Real Property Taxes." As used herein, the term
"Real Property Taxes" shall include any form of assessment; real estate,
general, special, ordinary or extraordinary, or rental levy or tax (other than
inheritance, personal income or estate taxes) improvement bond; and/or license
fee imposed upon or levied against any legal or equitable interest of Lessor in
the Premises, Lessor's right to other income therefrom, and/or Lessor's business
of leasing, by any authority having the direct or indirect power to tax and
where the funds are generated with reference to the Building address and where
the proceeds so generated are to be applied by the city, county or other local
taxing authority of a jurisdiction within which the Premises are located. The
term "Real Property Taxes" shall also include any tax, fee, levy, assessment or
charge, or any increase therein, imposed by reason of events occurring during
the term of this Lease, including but not limited to, a change in the ownership
of the Premises.

         10.2
                  (a) Payment of Taxes. Lessee shall pay the Real Property Taxes
applicable to the Premises during the term of this Lease. Subject to paragraph
10.2(b), all such payments shall be made at least ten (10) days prior to any
delinquency date. Lessee shall promptly furnish Lessor with satisfactory
evidence that such taxes have been paid. If any such taxes shall cover any
period of time prior to or after the expiration or

                  PAGE 6                             Initials /s/RBG /s/DBR
<PAGE>
termination of this Lease, lessee's share of such taxes shall be prorated to
cover only that portion of the tax bill applicable to the period that this Lease
is in effect, and Lessor shall reimburse lessee for any overpayment. If Lessee
shall fail to pay any required Real property Taxes, Lessor shall have the right
to pay the same, and Lessee shall reimburse lessor therefor upon demand.
                  (b) Advance Payment. In the event Lessee incurs a late charge
for 3 consecutive months on any Rent payment, Lessor may, at Lessor's option,
estimate the current Real Property Taxes, and required that such taxes be paid
in advance to Lessor by Lessee, either: (i) in a lump sum amount equal to the
installment due, at least twenty (3) days prior to the applicable delinquency
date, or (ii) monthly in advance with the payment of the Base Rent. If Lessor
elects to require payment monthly in advance, the monthly payment shall be an
amount equal to the amount of the estimated installment of taxes divided by the
number of months remaining before the month in which said installment become
delinquent. When the actual amount of the applicable tax bill is known, the
amount of such equal monthly advance payment shall be adjusted as required to
provide the funds needed to pay the applicable taxes. If the amount collected by
Lessor is insufficient to pay such Real Property Taxes when due, Lessee shall
pay Lessor, upon demand, such additional sums as are necessary to pay such
obligations. All moneys paid to Lessor under this Paragraph may be intermingled
with other moneys of Lessor and shall not bear interest. In the event of a
Breach by lessee in the performance of its obligations under this Lease, then
any balance of funds paid to Lessor under the provisions of this Paragraph may
at the option of Lessor, be treated as an additional Security Deposit.

         10.3 Joint Assessment. If the premises are not separately assessed,
lessee's liability shall be an equitable proportion of the Real Property Taxes
for all of the land and improvements included within the tax parcel assessed,
such proportion to be conclusively determined by Lessor from the respective
valuations assigned in the assessor's work sheets or such other information as
may be reasonably available.

         10.4 Personal Property Taxes. Lessee shall pay, prior to delinquency,
all taxes assessed against and levied upon Lessee Owned Alteration, Utility
Installations, Trade Fixtures, furnishings, equipment and all personal property
of Lessee. When possible, Lessee shall cause such property to be assessed and
billed separately from the real property of Lessor. If any of Lessee's said
personal property shall be assessed with Lessor's real property, Lessee shall
pay Lessor the taxes attributable to Lessee's property within ten (10) days
after receipt of a written statement.

11. Utilities. Lessee shall pay for all water, gas, heat, light, power,
telephone, trash disposal and other utilities and services supplied to the
Premises, together with any taxes thereon. If any such services are not
separately metered to Lessee, Lessee shall pay a reasonable proportion, to be
determined by Lessor, of all charges jointly metered.

12.      Assignment and Subletting.

         12.1  Lessor's Consent Required.
                  (a) Lessee shall not voluntarily or be operation of law
assign, transfer, mortgage or encumber (collectively, "assign or assignment") or
sublet all or any part of Lessee's interest in this lease or in the Premises
without Lessor's prior written consent.
                  (b) A change in the control of Lessee shall constitute an
assignment requiring consent. The transfer, on a cumulative basis, of fifty
percent (50%) or more of the voting control of Lessee shall constitute a change
in control for this purpose.
                  (c) The involvement of Lessee or its assets in any
transaction, or series of transactions (by way of merger, sale, acquisition,
financing, transfer, leveraged buy-out or otherwise), whether or not a formal
assignment or hypothecation of this Lease or Lessee's assets occurs, which
results or will result in a reduction of the Net Worth of Lessee by an amount
greater than twenty-five percent (25%) of such Net Worth as it was represented
at the time of the execution of this Lease or at the time of the most recent
assignment to which Lessor has consented, or as it exists immediately prior to
said transaction or transactions constituting such reduction, whichever was or
is greater, shall be considered an assignment of this Lease to which Lessor may
withhold its consent. "Net Worth of Lessee" shall mean the net worth of Lessee
(excluding any guarantors) established under generally accepted accounting
principles.
                  (d) An assignment or subletting without consent shall, at
Lessor's option, be a Default curable after notice per Paragraph 13.1(c), or a
noncurable Breach without the necessity of any notice and grace period. If
Lessor elects to treat such unapproved assignment or subletting as a noncurable
Breach, Lessor may either: (i) terminate this Lease, or (ii) upon thirty (30)
days written notice, increase the monthly Base Rent to one hundred ten percent
(110%) of the Base Rent then in effect. Further, in the event of such Breach and
rental adjustment, (i) the purchase price of any option to purchase the Premises
held by Lessee shall be subject to similar adjustment to one hundred ten percent
(110%) of the price previously in effect, and (ii) all fixed and non-fixed
rental adjustments scheduled during the remainder of the Lease term shall be
increased to One Hundred Ten Percent (110%) of the scheduled adjusted rent.
                  (e) Lessee's remedy for any breach of Paragraph 12.1 by Lessor
shall be limited to compensatory damages and/or injunctive relief.

         12.2  Terms and Conditions Applicable to Assignment and Subletting.
                  (a) Regardless of Lessor's consent, any assignment or
subletting shall not: (i) be effective without the express written assumption by
such assignee or sublessee of the obligations of Lessee under this Lease, (ii)
release lessee of any obligations hereunder, or (iii) alter the primary
liability of Lessee for the payment of Rent or for the performance of any other
obligations to be performed by Lessee.
                  (b) Lessor may accept Rent or performance of Lessee's
obligations from any person other than Lessee pending approval or disapproval of
an assignment. Neither a delay in the approval or disapproval of such assignment
nor the acceptance of Rent or performance shall constitute a waiver or estoppel
of Lessor's right to exercise its remedies for Lessee's Default or Breach.
                  (c) Lessor's consent to any assignment or subletting shall not
constitute a consent to any subsequent assignment or subletting.
                  (d) In the event of any Default or Breach by Lessee, Lessor
may proceed directly against Lessee, any Guarantors or anyone else responsible
for the performance of Lessee's obligations under this Lease, including any
assignee or sublessee, without first exhausting Lessor's remedies against any
other person or entity responsible therefore to Lessor, or any security held by
Lessor.
                  (e) Each request for consent to an assignment or subletting
shall be in writing, accompanied by information relevant to Lessor's
determination as to the financial and operational responsibility and
appropriateness of the proposed assignee or sublessee, including but not limited
to the intended use and/or required modification of the premises, if any,
together with a fee of exact attorney invoice of the current monthly Base Rent
applicable to the portion of the Premises which is the subject of the proposed
assignment or sublease, whichever is greater, as consideration for Lessor's
considering and processing said request. Lessee agrees to provide Lessor with
such other or additional information and/or documentation as may be reasonably
requested.
                  (f) Any assignee of, or sublessee under, this Lease shall, by
reason of accepting such assignment or entering into such sublease, be deemed to
have assumed and agreed to conform and comply with each and every term,
covenant, condition and obligation herein to be observed or performed by Lessee
during the term of said assignment or sublease, other than such obligations as
are contrary to or inconsistent with provisions of an assignment or sublease to
which Lessor has specifically consented to in writing.

         12.3 Additional Terms and Conditions Applicable to Subletting. The
following terms and conditions shall apply to any subletting by Lessee of all or
any part of the Premises and shall be deemed included in all subleases under
this Lease whether or not expressly incorporated therein:
                  (a) Lessee hereby assigns and transfers to lessor all of
Lessee's interest in all Rent payable on any sublease, and Lessor may collect
such Rent and apply same toward Lessee's obligations under this Lease; provided,
however, that until a Breach shall occur in the performance of Lessee's
obligations, Lessee may collect said Rent. Lessor shall not, by reason of the
foregoing or any assignment of such sublease, nor by reason of the collection of
Rent, be deemed liable to the sublessee for any failure of Lessee to perform and
comply with any of Lessee's obligations of such sublessee. Lessee hereby
irrevocably authorizes and directs any such sublessee, upon receipt of a written
notice from Lessor stating that a Breach exists in the performance of Lessee's
obligations under this Lease, to pay to Lessor all Rent due and to become due
under the sublease. Sublease shall rely upon any such notice from Lessor and
shall pay all Rents to Lessor without any obligation or right to inquire as to
whether such Breach exists, notwithstanding any claim from Lessee to the
contrary.
                  (b) In the event of a Breach by Lessee, Lessor may, at its
option, require sublessee to attorn to Lessor, in which event Lessor shall
undertake the obligations of the sublessor under such sublease from the time of
the exercise of said option to the expiration of such sublease; provided,
however, Lessor shall not be liable for any prepaid rents or security deposit
paid by such sublessee to such sublessor or for any prior Defaults or Breaches
of sublessor.

                   PAGE 7                             Initials /s/RBG /s/DBR
<PAGE>
                  (c) Any matter requiring the consent of the sublessor under a
sublease shall also require the consent of Lessor.
                  (d) No sublessee shall further assign or sublet all or any
part of the Premises without Lessor's prior written consent.
                  (e) Lessor shall delivery a copy of any notice of Default or
Breach by Lessee to the sublessee, who shall have the right to cure the Default
of Lessee within the grace period, if any, specified in such notice. The
sublessee shall have a right of reimbursement and offset from and against Lessee
for any such Defaults cured by the sublessee.

13.      Default; Breach; Remedies.

         13.1 Default; Breach. A "Default" is defined as a failure by the Lessee
to comply with or perform any of the terms, covenants, conditions or rules under
this Lease. A "Breach" is defined as the occurrence of one or more of the
following Defaults, and the failure of Lessee to cure such Default within any
applicable grace period.
                  (a) The abandonment of the Premises; or the vacating of the
Premises without providing a commercially reasonable level of security, or where
the coverage of the property insurance described in Paragraph 8.3 is jeopardized
as a result thereof, or without providing reasonable assurances to minimize
potential vandalism.
                  (b) The failure of y Lessee to make any payment of Rent or any
other monetary payment required to be made by Lessee hereunder, whether to
Lessor or to a third party, when due, to provide reasonable evidence of
insurance or surety bond or to fulfill any obligation under this Lease which
endangers or threatens life or property, where such failure continues for a
period of five (5) days following written notice thereof to Lessee.
                  (c) The failure by Lessee to provide upon request (i)
reasonable written evidence of compliance with Applicable Requirements, (ii)
(deleted), (iii) the rescission of an unauthorized assignment or subletting,
(iv) a Tenancy Statement, (v) a requested subordination, (vi) evidence
concerning any guaranty and/or Guarantor, (vii) any document requested under
Paragraph 42 (easements), or (viii) any other documentation or information which
Lessor may reasonably require of Lessee under the terms of this Lease, where any
such failure continues for a period of ten (10) days following written notice to
Lessee. o observe or perform any of the covenants, conditions or provisions of
this Lease to be observed or performed by Lessee, other than described in
paragraph (b) above, where such failure shall continue for a period of 30 days
after written notice thereof from Lessor to Lessee; provided, however, that if
the nature of Lessee's default is such that more than 30 days are reasonably
required for its cure, then Lessee shall not be deemed to be in default if
Lessee commenced such cure within said 30-day period and thereafter diligently
prosecutes such cure to completion.
                  (d) A Default by Lessee as to the terms, covenants, conditions
or provisions of this Lease, or of the rules adopted under Paragraph 40 hereof,
other than those described in subparagraphs 13.1(a), (b) or (c), above, where
such Default continues for a period of thirty (30) days after written notice;
provided, however, that if the nature of Lessee's Default is such that more than
thirty (30) days are reasonably required for its cure, then it shall be deemed
to be a Breach if Lessee commences such cure within said thirty (30) day period
and thereafter diligently prosecutes such cure to completion.
                  (e) The occurrence of any of the following events: (i) the
making of any general arrangement or assignment for the benefit of creditors;
(ii) becoming a "debtor" as defined in 11 U.S.C. 101 or any successor statute
thereto (unless, in the case of a petition filed against Lessee, the same is
dismissed within 60 days); (iii) the appointment of a trustee or receiver to
take possession of substantially all of Lessee's assets located at the Premises
or of Lessee's interest in this Lease, where possession is not restored to
Lessee within 30 days; or (iv) the attachment, execution or other judicial
seizure of substantially all of Lessee's assets located at the Premises or of
Lessee's interest in this Lease, where such seizure is not discharged within
thirty (30) days; provided, however, in the event that any provision of this
paragraph (e) is contrary to any applicable law, such provision shall be of no
force or effect, and not affect the validity of the remaining provisions.
                  (f) The discovery by Lessor that any financial statement of
Lessee or of any Guarantor given to Lessor was materially false.
                  (g)      If the performance of Lessee's obligations under
this Lease is guaranteed; (i)

         13.2 Remedies. If Lessee fails to perform any of its affirmative duties
or obligations, within ten (10) days after written notice (or in case of
emergency, without notice), Lessor may, at its option, perform such duty or
obligation on Lessee's behalf, including but not limited to the obtaining of
reasonably required bonds, insurance policies, or governmental licenses, permits
or approvals. The costs and expenses of any such performance by Lessor shall be
due and payable by Lessee upon receipt of invoice therefore. If any check given
to Lessor by Lessee shall not be honored by the bank upon which it is drawn,
Lessor, at its option, may require all future payments to be made by lessee to
be by cashier's check. In the event of a Breach, Lessor may, with or without
further notice or demand, and without limiting Lessor in the exercise of any
right or remedy which Lessor may have by reason of such Breach:
                  (a) Terminate Lessee's right to possession of the Premises by
any lawful means, in which case this Lease shall terminate and Lessee shall
immediately surrender possession of the Premises to Lessor. In such event Lessor
shall be entitled to recover from Lessee: (i) the unpaid Rent which had been
earned at the time of termination; (ii) the worth at the time of award of the
amount by which the unpaid rent which would have been earned after termination
until the time of award exceeds the amount of such rental loss that the Lessee
proves could have been reasonably avoided; (iii) the worth at the time of award
of the amount by which the unpaid rent for the balance of the term after the
time of award exceeds the amount of such rental loss that the Lessee proves
could be reasonably avoided; and (iv) any other amount necessary to compensate
Lessor for all the detriment proximately caused by the Lessee's failure to
perform its obligations under this Lease or which in the ordinary course of
things would be likely to result therefrom including but not limited to the cost
of recovering possession of the Premises, expenses of reletting, including
necessary renovation and alteration of the Premises, reasonable attorneys' fees,
and that portion of any leasing commission paid by Lessor in connection with
this Lease applicable to the unexpired term of this Lease. The worth at the time
of award of the amount referred to in provision (iii) of the immediately
preceding sentence shall be computed by discounting such amount at the discount
rate of the Federal Reserve Bank of the District within which the Premises are
located at the time of award plus one percent (1%). Efforts by Lessor to
mitigate damages caused by Lessee's Breach of this Lease shall not waive
Lessor's right to recover damages under Paragraph 12. If termination of this
Lease is obtained through the provisional remedy of unlawful detainer, Lessor
shall have the right to recover in such proceeding any unpaid Rent and damages
are recoverable therein, or Lessor may reserve the right to recover all or any
part thereof in a separate suit. IF a notice and g race period required under
Paragraph 13.1 and the unlawful detainer statute shall run concurrently, and the
failure of Lessee to cure the Default within the greater of the two grace
periods shall constitute both an unlawful detainer and a Breach of this Lease
entitling Lessor to the remedies provided for in this Lease and/or said statute.
                  (b) Continue the Lease and Lessee's right to possession and
recover the Rent as it becomes due, in which event Lessee may sublet or assign,
subject only to reasonable limitation. Acts of maintenance, efforts to relet,
and/or the appointment of a receiver to protect the Lessor's interests, shall
not constitute a termination of the Lessee's right to possession.
                  (c) Pursue any other remedy now or hereafter available under
the laws or judicial decisions of the state wherein the Premises are located.
The expiration of termination of this Lease and/or the termination of Lessee's
right to possession shall not relieve Lessee from liability under any indemnity
provisions of this Lease as to matters occurring or accruing curing the term
hereof or by reason of Lessee's occupancy of the Premises.

         13.3 Inducement Recapture. Any agreement for free or abated rent or
other charges, or for the giving or paying by Lessor to or for Lessee of any
cash or other bonus, inducement or consideration for Lessee's entering into this
Lease, all of which concessions are hereinafter referred to as "Inducement
Provisions", shall be deemed conditioned upon Lessee's full and faithful
performance of all of the terms, covenants, and conditions of this Lease. Upon
Breach of this Lease by Lessee, any such Inducement Provision shall
automatically be deemed deleted from this Lease and of no further force or
effect, and any rent, other charge, bonus, inducement or consideration
theretofore abated, given or paid by Lessor under such Inducement Provision
shall be immediately due and payable by Lessee to Lessor, notwithstanding any
subsequent cure of said Breach by Lessee. The acceptance by Lessor of rent or
the cure of the Breach which initiated the operation of this paragraph shall not

                     PAGE 8                             Initials /s/RBG /s/DBR
<PAGE>
be deemed a waiver by Lessor of the provisions of this paragraph unless
specifically so stated in writing by Lessor at the time of such acceptance.

         13.4 Late Charges. Lessee hereby acknowledges that late payment by
Lessee of Rent will cause Lessor to incur costs not contemplated by this Lease,
the exact amount of which will be extremely difficult to ascertain. Such costs
include, but are not limited to, processing and accounting charges, and late
charges which may be imposed upon Lessor by any Lender. Accordingly, if any Rent
shall not be received by Lessor or within five (5) days after such amount shall
be due, then, without any requirement for notice to Lessee, Lessee shall pay to
Lessor a one-time late charge equal to ten percent (10%) of such overdue amount.
The parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Lessor will incur by reason of late payment by Lessee.
Acceptance of such late charge by Lessor shall in no event constitute a waiver
of Lessee's Default or Breach with respect to such overdue amount, nor prevent
the exercise of any of the other rights and remedies granted hereunder. In the
event that a late charge is payable hereunder, whether or not collected, for
three (3) consecutive installments of Base Rent, then notwithstanding any
provision of this Lease to the contrary, Base Rent shall, at Lessor's option,
become due and payable quarterly in advance.

         13.5 Interest. Any monetary payment due Lessor hereunder, other than
late charges, not received by lessor within thirty (30) days following the date
on which it was due, shall bear interest from the thirty-first (31st) day after
it was due. The interest ("Interest") charged shall be equal to the prime rate
charged by the largest state chartered bank in the state in which the Premises
are located plus 4%, but shall not exceed the maximum rate allowed by law.
Interest is payable in addition to the potential late charge provided for in
Paragraph 13.4.

         13.6  Breach by Lessor.
                  (a) Notice of Breach. Lessor shall not be deemed in breach of
this Lease unless Lessor fails within a reasonable time to perform an obligation
required to be performed by Lessor. For purposes of this paragraph, a reasonable
time shall in no event be less than thirty (30) days after receipt by Lessor,
and any Lender whose name and address shall have been furnished Lessee in
writing for such purpose, of written notice specifying wherein such obligation
of Lessor has not been performed; provided however, that if the nature of
Lessor's obligation is such that more than thirty (30) days are reasonably
required for its performance, then Lessor shall not be in breach if performance
is commenced within such thirty (3) day period and thereafter diligently pursued
to completion.
                  (b) Performance by Lessee on Behalf of Lessor. In the event
that neither Lessor nor Lender cures said breach within thirty (30) days after
receipt of said notice, or if having commenced said cure they do not diligently
pursue it to completion, then Lessee may elect to cure said breach at Lessee's
expense and offset from Rent an amount equal to the greater of one month's base
Rent or the Security Deposit, and to pay an excess of such expense under
protest, reserving Lessee's right to reimbursement from Lessor. Lessee shall
document the cost of said cure and supply said documentation to Lessor.

14. Condemnation. If the Premises or any portion thereof are taken under the
power of eminent domain or sold under the threat of the exercise of said power
(collectively "Condemnation"), this Lease shall terminate as to the part taken
as of the date the condemning authority takes title or possession, whichever
first occurs. If more than ten percent (10%) of any building, or more than
twenty-five percent (25%) of the land area not occupied by any building, is
taken by Condemnation, Lessee may, at Lessee's option, to be exercised in
writing within ten (10) days after Lessor shall have given lessee written notice
of such taking (or in the absence of such notice, within ten (10) days after the
condemning authority shall have taken possession) terminate this Lease as of the
date the condemning authority takes such possession. If Lessee does not
terminate this Lease in accordance with the foregoing, this Lease shall remain
in full force and effect as to the portion of the Premises remaining, except
that the Base Rent shall be reduced in proportion to the reduction in utility of
the Premises caused by such Condemnation. Condemnation awards and/or payments
shall be the property of Lessor, whether such award shall be made as
compensation for diminution in value of the leasehold, the value of the part
taken, or for severance damages; provided, however, that Lessee shall be
entitled to any compensation for Lessee's relocation expense, loss of business
goodwill and/or Trade Fixtures, without regard to whether or not this Lease is
terminated pursuant to the provisions of this Paragraph. All Alterations and
Utility Installations made to the Premises by Lessee, for purposes of
Condemnation only, shall be considered the property of the Lessee and Lessee
shall be entitled to any and all compensation which is payable therefor. In the
event that this Lease is not terminated by reason of the Condemnation, Lessor
shall repair any damage to the Premises caused by such Condemnation.

15. Brokers' Fee.

         15.1 Additional Commission. In addition to the payment sowed pursuant
to paragraph 1.10 above, and unless Lessor and the Brokers otherwise agree in
writing, Lessor agrees that: (a) if Lessee exercises any Option, (b) if Lessee
acquires any rights to the Premises or other premises owned by Lessor and
located within the same Project, if any, within which the Premises is located,
(c) if Lessee remains in possess of the Premises, with the consent of Lessor,
after the expiration of this Lease, or (d) if Base Rent is increased, whether by
agreement or operation of an escalation clause herein, then, Lessor shall pay
Brokers a fee in accordance with the schedule of said Brokers in effect at the
time of the execution of this Lease.

         15.2 Assumption of Obligations. Any buyer or transferee of Lessor's
interest in this Lease shall be deemed to have assumed Lessor's obligation
hereunder. Each Broker shall be a third party beneficiary of the provisions of
Paragraphs 1.10, 15, 22 and 31. If Lessor fails to pay to a Broker any amounts
due as and for commissions pertaining to this Lease when due, then such amounts
shall accrue interest. In addition, if Lessor fails to pay any amounts to
Lessee's Broker when due, Lessee's Broker may send written notice to Lessor and
Lessee of such failure and if Lessor fails to pay such amounts within ten (10)
days after said notice, Lessee shall pay said monies to its Broker and offset
such amounts against Rent. In addition, Lessee's Broker shall be deemed to be a
third party beneficiary of any commission agreement entered into by and/or
between Lessor and Lessor's Broker.

         15.3 Representations and Indemnities of Broker Relationships. Lessee
and Lessor each represent and warrant to the other that it has had no dealings
with any person, firm, broker or finder (other than the Brokers, if any) in
connection with this Lease, and that no one other than said named Brokers is
entitled to any commission or finder's fee in connection herewith. Lessee and
Lessor do each hereby agree to indemnify, protect, defend and hold the other
harmless from and against liability for compensation or charges which may be
claimed by any such unnamed broker, finder or other similar party by reason of
any dealings or actions of the indemnifying Party, including any costs,
expenses, attorney's fees reasonably incurred with respect thereto.

16.      Tenancy Statement/Estoppel Certificate

         16.1 Each party (as "Responding Party") shall within ten (10) days'
prior written notice from the other Party (the "Requesting Party") execute,
acknowledge and deliver to the Requesting Party and estoppel certificate in
writing, in form similar to the then most current "Tenancy Statement" form
published by the American Industrial Real Estate Association, plush such
additional information, confirmation and/or statements as may be reasonably
requested by the Requested Party.

         16.2 If Lessor desires to finance, refinance, or sell the Premises, or
any part thereof, Lessee and all Guarantors shall deliver to any potential
lender or purchaser designated by Lessor such financial statements of Lessee as
may be reasonably required by such lender or purchaser, including but mot
limited to Lessee's financial statements for the past three (3) years. All such
financial statements shall be received by Lessor and such lender or purchaser in
confidence and shall be used only for the purposes herein set forth.

17. Definition of Lessor. The term "Lessor" as used herein shall mean the owner
or owners at the time in question of the fee title to the Premises, or, if this
is a sublease, of the Lessee's interest in the prior lease. In the event of a
transfer of Lessor's title or interest in the Premises or this Lease, Lessor
shall deliver to the transferee or assignee (in cash or by credit) any unused
Security Deposit held by Lessor. Except as provided in Paragraph 15, upon such
transfer or assignment and delivery of the Security Deposit, as aforesaid, the
prior Lessor shall be relieved of all liability with respect to the obligations
and/or covenants under this Lease thereafter to be performed by the Lessor.
Subject to the foregoing, the obligations and/or covenants in this lease to be
performed by the Lessor shall be binding only upon the Lessor as hereinabove
defined. Notwithstanding the above, the original lessor under this lease, and
all subsequent holders of the Lessor's interest in this Lease shall remain
liable and responsible with regard to the potential duties and liabilities of
Lessor pertaining to hazardous Substances as outlined in paragraph 6 above and
the addendum.

18. Severability. The invalidity of any provision of this Lease, as determined
by a court of competent jurisdiction, shall in no way affect the validity of any
other provision hereof.

                   PAGE 9                             Initials /s/RBG /s/DBR
<PAGE>
19. Days. Unless otherwise specifically indicated to the contrary, the word
"days" as used in this Lease shall mean and refer to calendar days.

20.      (deleted)

21. Time of Essence. Time is of the essence with respect to the performance of
all obligations to be performed or observed by the Parties under this Lease.

22. No Prior or Other Agreements; Broker Disclaimer. This Lease contains all
agreements between the Parties with respect to any matter mentioned herein, and
no other prior or contemporaneous agreement or understanding shall be effective.
Lessor and Lessee each represents and warrants to the Brokers that it has made,
and is relying solely upon, its own investigation as to the nature, quality,
character and financial responsibility of the other Party to this Lease and as
to the nature, quality and character of the Premises. Brokers have no
responsibility with respect thereto or with respect to any default or breach
hereof by either party. The liability (including court costs and Attorney's
fees), of any Broker with respect to negotiation, execution, delivery or
performance by either Lessor or Lessee under this Lease or any amendment or
modification hereto shall be limited to an amount up to the fee received by such
Broker pursuant to this lease; provided, however, that the foregoing limitation
on each Broker's liability shall not be applicable to any gross negligence or
willful misconduct of such Broker.

23.      Notices.

         23.1 Notice Requirements. All notices required or permitted by this
Lease shall be in writing and may be delivered in person (by hand or by courier)
or may be sent by regular, certified or registered mail or U.S. postal Service
Express mail, with postage prepaid, or by facsimile transmission, and shall be
deemed sufficiently given if served in a manner specified in this Paragraph 23.
The addresses noted adjacent to a Party's signature on this Lease shall be that
Party's address for delivery or mailing of notices. Either Party may by written
notice to the other specify a different address for notice, except that upon
Lessee's taking possession of the Premises, the Premises shall constitute
Lessee's address for notice. A copy of all notices to Lessor shall be
concurrently transmitted to such party or parties at such addresses as Lessor
may from time to time hereafter designate in writing.

         23.2 Date of Notice. Any notice sent by registered or certified mail,
return receipt requested, shall be deemed given on the date of delivery shown on
the receipt card, or if no delivery date is shown, the postmark thereon. If sent
by regular mail the notice shall be deemed given forty-eight (48) hours after
the same is addressed as required herein and mailed with postage prepaid.
Notices delivery by United States Express mail or overnight courier that
guarantee next day delivery shall be deemed given twenty-four (24) hours after
delivery of the same to the Postal Service or courier. Notices transmitted by
facsimile transmission or similar means shall be deemed delivered upon telephone
confirmation of receipt, provided a copy is also delivered via delivery or mail.
If notice is received on a Saturday, Sunday or legal holiday, it shall be deemed
received on the next business day.

24. Waivers. No waiver by Lessor of the Default or Breach of any term, covenant
or condition hereof by Lessee, shall deemed a waiver of any other terms,
covenant or condition hereof, or of any subsequent Default or Breach by Lessee
of the same or any other term, covenant or condition hereof. Lessor's consent
to, or approval of, any act shall not be deemed to render unnecessary the
obtaining of Lessor's consent to, or approval of, any subsequent act by Lessee,
or be construed as the basis of an estoppel to enforce the provision or
provisions of this Lease requiring such consent. The acceptance of Rent
hereunder by Lessor shall not be a waiver of any Default or Breach by Lessee.
Any payment made by Lessee in connection therewith, which such statements and/or
conditions shall be of no force or effect whatsoever unless specifically agreed
to writing by Lessor at or before the time of deposit of such payment.

25. Recording. Either Lessor or Lessee shall, upon request of the other,
execute, acknowledge and deliver to the other a "short form" memorandum of this
Lease for recording purposes. The Party requesting recordation shall be
responsible for payment of any fees applicable thereto.

26. No Right to Holdover. Lessee has no right to retain possession of the
Premises or any part thereof beyond the expiration or termination of this Lease.
In the event that Lessee holds over, then the Base Rent shall be increased to
one hundred fifty percent (150%) of the Base Rent applicable during the month
immediately preceding the expiration or termination. Nothing contained herein
shall be construed as consent by Lessor to any holding over by Lessee.

27. Cumulative Remedies. No remedy or election hereunder shall be deemed
exclusive but shall, wherever possible, be cumulative with all other remedies at
law or in equity.

28. Covenants and Conditions; Construction of Agreement. All provisions of this
Lease to be observed or performed by Lessee are both covenants and conditions.
In construing this Lease, all headings and titles are for the convenience of the
parties only and shall not be considered a part of this Lease. Whenever required
by the context, the singular shall include the plural and vice versa. This Lease
shall not be construed as if prepared by one of the parties, but rather
according to its fair meaning as a whole, as if both parties had prepared it.

29. Binding Effect; Choice of Law. This Lease shall be binding upon the parties,
their personal representatives, successors and assigns and be governed by the
laws of the State in which the Premises are located. Any litigation between the
Parties hereto concerning this Lease shall be initiated in the county in which
the Premises are located.

30.      Subordination; Attornment; Non-Disturbance.

         30.1 Subordination. This Lease and any Option granted hereby shall be
subject and subordinate to any ground lease, mortgage, deed of trust, or other
hypothecation or security device (collectively, "Security Device"), now or
hereafter place upon the Premises, to any and all advances made on the security
thereof, and to all renewals, modifications, and extensions thereof. Lessee
agrees that the holders of any such Security Devices shall have no liability or
obligation to perform any of the obligations of Lessor under this lease. Any
Lender may elect to have this Lease and/or any Option granted hereby superior to
the lien of its Security Device by giving written notice thereof to Lessee, this
Lease and such Options shall be deemed prior to such Security Device,
notwithstanding the relative dates of the documentation or recordation thereof.

         30.2 Attornment. Subject to the non-disturbance provisions of Paragraph
30.3, lessee agrees to attorn to a Lender or any other party who acquired
ownership of the Premises by reason of a foreclosure of a Security Device, and
that in the event of such foreclosure, such new owner shall not: (i) be liable
for any act or omission of any prior lessor or with respect to event occurring
prior to acquisition of ownership. (ii) be bound by prepayment of more than one
(1) month's rent.

         30.3 Non-disturbance. With respect to Security Devices entered into by
Lessor after the execution of this Lease, lessee's subordination of this Lease
shall be subject to receiving a commercially reasonable non-disturbance
agreement (a "Non-Disturbance Agreement") from the Lender which Non-Disturbance
Agreement provides that Lessee's possession of the Premises, and this lease,
including any options to extend the term hereof, will not be disturbed so long
as Lessee is not in Breach hereof and attorns to the record owner of the
Premises. Further, within sixty (60) days after the execution of this Lease,
lessor shall use its commercially reasonable efforts to obtain a Non-Disturbance
Agreement from the holder of any pre-existing Security Device which is secured
by the Premises. In the event that Lessor is unable to provide the
Non-Disturbance Agreement within said sixty (60) days, then Lessee may, at
Lessee's option, directly contact lessor's lender and attempt to negotiate for
the execution and delivery of a Non-Disturbance Agreement.

         30.4 Self-Executing. The agreements contained in this Paragraph 30
shall be effective without the execution of any further documents; provided,
however, that, upon written request from lessor or a Lender in connection with a
sale, financing or refinancing of the Premises, Lessee and Lessor shall execute
such further writings as may be reasonably required to separately document any
subordination, attornment and/or Non-Disturbance Agreement provided for herein.

31. Attorneys' Fees. If any Party or Broker brings an action or proceeding to
enforce the terms hereof or declare rights hereunder, the Prevailing Party (as
hereafter defined) in any such proceeding, action, or appeal thereon, shall be
entitled to reasonable attorneys' fees. Such fees may be awarded in the same
suit or recovered in a separate suit, whether or not such action or proceeding
is pursuant to decision or

                 PAGE 10                            Initials /s/RBG /s/DBR
<PAGE>
judgment. The term, "Prevailing Party" shall include, without limitation, a
Party or Broker who substantially obtains or defeats the relief sought, as the
case may be, whether by compromise, settlement, judgment, or the abandonment by
the other Party or Broker of its claim or defense. The attorneys' fees award
shall not be computed in accordance with any court fee schedule, but shall be
such as to fully reimburse all attorney's fees reasonably incurred. In addition,
lessor shall be entitled to attorney's fees, costs and expenses incurred in the
preparation and service of notices of Default and consultations in connection
therewith, whether or not a legal action is subsequently commenced in connection
with such Default or resulting Breach.

32. Lessor's Access; Showing Premises; Repairs. Lessor and lessor's agents shall
have the right to enter the Premises at any time, in the case of an emergency,
and otherwise at reasonable times for the purpose of showing the same to
prospective purchases, lenders, or lessees, and making such alterations,
repairs, improvements or additions to the Premises as Lessor is entitled to make
under the Lease. All such activities shall be without abatement of rent or
liability to Lessee. Lessor may at any time place on the premises any ordinary
"For Sale" signs and Lessor may during the last six (6) months of the term
hereof place on the premises any ordinary "for Lease" signs. Lessee may at any
time place on or about the Premises any ordinary "for sublease" sign.

33. Auctions. Lessee shall not conduct, nor permit to be conducted, any auction
upon the Premises without Lessor's prior written consent. Lessor shall not be
obligated to exercise any standard of reasonableness in determining whether to
permit an auction.

34. Signs. Except for ordinary "For Sublease" signs, lessee shall not place any
sign upon the Premises without Lessor's prior written consent. All signs must
comply with all Applicable Requirements.

35. Termination; Merger. Unless specifically stated otherwise in writing by
Lessor, the voluntary or other surrender of this Lease by Lessee, the mutual
termination or cancellation hereof, or a termination hereof by Lessor for Breach
by Lessee, shall automatically terminate any sublease or lesser estate in the
Premises; provided, however, that Lessor may elect to continue any one or all
existing subtenancies. Lessor's failure within ten (10) days following any such
event to elect to the contrary by written notice to the holder of any such
lesser interest, shall constitute Lessor's election to have such event
constitute the termination of such interest.

36. Consents. Except as otherwise provided herein, wherever in this Lease the
consent of a Party is required to an act by or for the other party, such consent
shall not be unreasonably withheld or delayed. Lessor's actual reasonable costs
and expenses (including but not limited to architects', attorneys', engineers'
and other consultants' fees) incurred in the consideration of, or response to, a
request by Lessee for any Lessor consent, including but not limited to consents
to an assignment, a subletting or the presence or use of a Hazardous Substance,
shall be paid by Lessee upon receipt of an invoice and supporting documentation
therefor. Lessor's consent to any act, assignment or subletting shall not
constitute an acknowledgment that no Default or Breach by Lessee of this lease
exists, nor shall such consent be deemed a waiver of any then existing Default
or Breach, except as may be otherwise specifically stated in writing by Lessor
at the time of such consent. The failure to specify herein any particular
condition to Lessor's consent shall not preclude the imposition by Lessor at the
time of consent of such further or other conditions as are then reasonable with
reference to the particular matter for which consent is being given. In the
event that either Party disagrees with any determination made by the other
hereunder and reasonably requests the reasons for such determination, the
determining party shall furnish its reasons in writing and in reasonable detail
within ten 910) business days following such request.

37.      Guarantor
         37.1 Execution. The Guarantors, if any, shall each execute a guaranty
in the form most recently published by the American Industrial Real Estate
Association, and each such Guarantor shall have the same obligations as Lessee
under this Lease.
         37.2 Default. It shall constitute a Default of the Lessee if any
guarantor fails or refuses, upon request to provide: (a) evidence of the
execution of the guaranty, including the authority of the party signing on
guarantor's behalf to obligate Guarantor, and in the case of a corporate
Guarantor, a certified copy of a resolution of its board of directors
authorizing the making of such guaranty, (b) current financial statements, 9c) a
Tenancy Statement, or (d) written confirmation that the guaranty is still in
effect.

38. Quiet Possession. Subject to payment by Lessee of the Rent and performance
of all of the covenants, conditions and provisions on Lessee's part to be
observed and performed under this Lease, Lessee shall have quiet possession and
quiet enjoyment of the Premises during the term hereof.

39.      Options.
         39.1 Definition. "Option" shall mean: (a) the right to extend the term
of or renew this Lease or to extend or renew any lease that Lessee has on other
property of Lessor; (b) the right of first refusal or first offer to lease
either the Premises or other property of Lessor; (c) the right to purchase or
the right of first refusal to purchase the Premises or other property of Lessor.

         39.2 Options Personal to Original Lessee. Each Option granted to Lessee
in this Lease are personal to Lessee and cannot be assigned or exercised by
anyone other than said original Lessee and while the original Lessee is in full
possession of the Premises and, if requested by Lessor, with Lessee certifying
that Lessee has no intention of thereafter assigning or subletting.

         39.3 Multiple Options. In the event that Lessee has any multiple
options to extend or renew this Lease, a later option cannot be exercised unless
the prior Options have been validly exercised.
         39.4  Effect of Default on Options.
                  (a) Lessee shall have no right to exercise an Option:, (i)
during the period commencing from the giving of notice of Default and continuing
until said Default is cured (ii) during the period of time any Rent is unpaid
(without regard to whether notice thereof is given Lessee), (iii) during the
time Lessee is in Breach of this Lease, or (iv) in the event that Lessee has
been given three (3) or more notices of Default, whether or not the defaults are
cured, during the twelve (12) month period immediately preceding the exercise of
the Option.
                  (b) The period of time within which an Option may be exercised
shall not be extended or enlarged by reason of Lessee's inability to exercise an
Option because of the provisions of paragraph 39.4(a).
                  (c) An Option shall terminate and be of no further force or
effect, notwithstanding Lessee's due and timely exercise of the Option, if,
after such exercise and prior to the commencement of the extended term, (i)
Lessee fails to pay to Rent for a period of thirty (30) days after such Rent
becomes due (without any necessity of Lessor to give notice thereof), or (ii)
Lessor gives to Lessee three (3) or more notices of separate Default during any
twelve (12) month period, whether or not the Defaults are cured, or (iii) if
Lessee commits a Breach of this Lease.

40. Multiple Buildings. If the Premises are a part of a group of buildings
controlled by Lessor, Lessee agrees that it will observe all reasonable rules
and regulations which Lessor may make from time to time for the management,
safety, and care of said properties, including the care and cleanliness of the
grounds and including the parking, loading and unloading of vehicles, and that
Lessee will pay its fair share of common expenses incurred in connection
therewith.

41. Security Measures. Lessee hereby acknowledges that the rental payable to
Lessor hereunder does not include the cost of guard service or other security
measures, and that Lessor shall have no obligation whatsoever to provide same.
Lessee assumes all responsibility for the protection of the Premises, Lessee,
its agents and invitees and their property from the acts of third parties.

42. Reservations. Lessor reserves to itself the right, from time to time, to
grant, without the consent or joinder of Lessee, such easements, rights and
dedications that Lessor deems necessary, and to cause the recordation of parcel
maps and restrictions, so long as such easements, rights, dedications, maps and
restrictions do not unreasonably interfere with the use of the Premises by
Lessee. Lessee agrees to sign any documents reasonably requested by Lessor to
effectuate any such easement rights, dedication, map or restrictions.

43. Performance Under Protest. If at any time a dispute shall arise as to any
amount or sum of money to be paid by one Party to the other under the provisions
hereof, the Party against whom the obligation to pay the money is asserted shall
have the right to make payment "under protest" and such payment shall not be
regarded as a voluntary payment, and there shall survive the right on the part
of said Party to institute suit for recovery of each sum. If it shall be
adjudged that there was no legal obligation on the part of said Party to pay
such sum or any part thereof, said Party shall be entitled to recover such sum
or so much thereof as it was not legally required to pay.

44. Authority. If either Party hereto is a corporation, trust, or general or
limited partnership, or similar entity, each individual executing this Lease on
behalf of such entity represents and warrants that he or she is duly authorized
to execute and deliver this Lease on its behalf. Each Party shall, within thirty
(30) days after request, deliver to the other Party satisfactory evidence of
such authority.

                       PAGE 11                            Initials /s/RBG /s/DBR
<PAGE>
45. Conflict. Any conflict between the printed provisions of this Lease and the
typewritten or handwritten provision shall be controlled by the typewritten or
handwritten provisions.

46. Offer. Preparation of this Lease by either Party or their agent and
submission of same to the other Party shall not be deemed an offer to lease to
the other Party. This lease is not intended to be binding until executed and
delivered by all parties hereto.

47. Amendments. This Lease may be modified only in writing, signed by the
Parties in interest at the time of the modification. As long as they do not
materially change Lessee's obligations hereunder, Lessee agrees to make such
reasonable non-monetary modifications to this lease as may be reasonably
required by a Lender in connection with the obtaining of normal financing or
refinancing of the Premises.

48. Multiple Parties. If more than one person or entity is named herein as
either Lessor or Lessee, such multiple Parties shall have joint and several
responsibility to comply with the terms of this Lease.

49. Mediation and Arbitration of Disputes. An Addendum requiring the Mediation
and/or the Arbitration of all disputes between the Parties and/or Brokers
arising out of this Lease (box) is (box) is not attached to this Lease.

LESSOR AND LESSEE HAVE CAREHULLY READ AND REVIEWED THIS LEASE AND EACH TERM AND
PROVISION CONTAINED HEREIN, AND BY THE EXEUCTION OF THIS LEASE SHOW THEIR
INFORMED AND VOLUNTARY CONSENT THERETO. THE PARTIES HEREBY AGREE THAT, AT THE
TIME THIS LEASE IS EXECUTED, THE TERMS OF THIS LEASE ARE COMMERCIALLY REASONABLE
AND EFFECTUATE THE INTENT AND PURPOSE OF LESSOR AND LESSEE WITH RESPECT TO THE
PREMISES.

The parties hereto have executed this Lease at the place and on the dates
specified above their respective signatures.

Executed at: (blank)                        Executed at: (blank)
on: (blank)                                          on: (blank)
By LESSOR:                                           By LESSEE:
Richard B. Gomez,                                    UroGenesys, Inc.
Josephine L. Gomez
TTEE U/A/D 10-31/1990 FBO
Gomez Family Trust
By:  /s/R.B. Gomez                          By:  /s/Donald B. Rice
Name Printed: (blank)                       Name printed: Donald B. Rice
Title: (blank)                              Title: President

                                            BROKER:
                                            CB Commercial
                                            Executed at: (blank)
                                            on: (blank)
                                            By: /s/Robert P. Dubbins
                                            Name Printed: Robert P. Dubbins
                                            Title: First Vice President

                                     PAGE 12


<PAGE>


ADDENDUM TO STANDARD INDUSTRIAL LEASE-NET DATED JANUARY 20, 1997 BY AND BETWEEN
RICHARD B. GOMEZ, JOSEPHINE L. GOMEZ, TTEE U/A/D 10-31/1990 FBO GOMEZ FAMILY
TRUST AS "LESSOR", AND UROGENESYS, INC. AS "LESSEE", FOR THE PREMISES KNOWN AS
1701 COLORADO AND 1553 17TH STREET, SANTA MONICA, CA 90404. IN THE EVENT OF ANY
CONFLICT BETWEEN THE TERMS OF THE ADDENDUM AND THOSE OF THE PRINTED LEASE, THE
ADDENDUM SHALL PREVAIL.

50.      6.2 HAZARDOUS SUBSTANCES:

         Lessee shall furnish the Lessor with a copy or copies State License
         that warrants that Lessee has the authorization of the use of Radio
         Active Materials and disposal of such for the term of this Lease from
         Radiologic Health Branch for the State Department of Health Services.

         Lessee to follow paragraph 6.2 through 6.2(g) of this Lease.

51.      LESSOR REPRESENTATION:

         To the best of Lessor's knowledge, there are no hazardous Substances
         present or about the Premises and no action, proceeding, or claim is
         pending or threatened concerning the Premises or Building concerning
         any hazardous Substances or pursuant to any environmental law, and
         Lessor is in full compliance with all environmental laws, with respect
         to the Premises.

52.      WARRANTIES:

         Lessor or Lessor's agents have not made any representation or warranty
         as to the suitability of the Premises, and that Lessee's Tenant's
         Improvements and equipment, for the conduct of Lessee's business;
         provided, however that Lessor represents that the Premises were
         suitable for the uses to which they were installed by Xoma Corp., prior
         to the commencement of this Lease. Subject to paragraphs 56 and 2,
         Lessee shall accept the Premises and all Tenant's Improvement,
         equipment, electrical, plumbing (HVAC), walls (interior) partitions,
         doors, etc. in its current "As-is" condition.

53.      8.0 INSURANCE:

     Line - 8.3 delete (loss payable to Lessor) insert with (Lessor as named
     insured)

54.      10.2 PROPERTY TAXES:

         Lessee shall pay the Real property Taxes applicable to the premises
         during the term of this Lease, however, Lessee agrees to make each
         payment to Lessor for reimbursement within ten (10) days from the date
         Lessor presents Lessee, copies of property tax bills, reflecting the
         assessments and mounts due therein.
<PAGE>

55.      12.1 LESSOR CONSENT TO SUBLETS:

         Lessor consents to Lessee's sublet of an approximately 1250 square foot
         portion of the larger brick building at 1553 17th Street, Santa Monica,
         California from March 1, 1997 through February 28, 1000 to Xoma
         Industries, inc. Lessee shall furnish lessor copies of lease (sub)
         agreements between Lessee and sublessee. Lessee agrees to furnish
         Lessor with Insurance certificates to comply with paragraph 8.0 through
         8.8 of this lease.

56.      GOVERNMENTAL COMPLIANCE & APPROVALS:

         Lessee shall not be responsible for any Federal, State or Local code
         compliance, environmental clean-up asbestos abatement, seismic upgrade
         or ADA violations or any restorations or alternations due to prior uses
         of the premises. In all other respects, but not to supersede Lessor's
         responsibility under paragraphs 2 and 52, Lessee shall accept the
         Premises in its current "As-is" condition.

57.      PROPOSITION 13 PROTECTION:

         Lessee shall not be responsible for the increase in real property taxes
         caused by a sale or transfer of the property.

58.      SURRENDER:

         Lessor acknowledges the modification of Paragraph 7.45 as follows:
         Lessor accepts XOMA Corporation as retaining its continuing obligations
         in respect of Paragraph 7.2 in terms of its lease dated June 22, 1995,
         and agrees that the obligations of Lessee with regard to the condition
         of the premises upon termination of the Lease and surrender of same,
         shall be limited to the terms of the letter dated January 20, 1997
         received from XOMA Corporation, and attached hereto as Appendix A.
<PAGE>
                               OPTION(S) TO EXTEND
                                   ADDENDUM TO
                                 STANDARD LEASE

         Dated January 20, 1997

         By and Between (Lessor)    Richard B. Gomez, Josephine L. Gomez,
         TTEE U/A/D 10-31/1990 FBO Gomez Family Trust

               (Lessee)UroGenesys, Inc., a California corporation
         Property Address: 1701 Colorado and 1553 17th Street, 
         Santa Monica, CA 90404

Paragraph 59

A. OPTION(S) TO EXTEND:

         Lessor hereby grants to lessee the option to extend the term of this
Lease for 1 additional 36 month period(s) commencing when the prior term expires
upon each and all of the following terms and conditions:

         (i) Lessee gives to Lessor, and Lessor actually receives on a date
which is prior to the date that the option period would commence (if exercised)
by at least 6 and not more than 9 month, a written notice of the exercise of the
option(s)to extend this Lease for said additional term(s), time being of
essence. If said notification of the exercise of said option(s)is(are) not so
given and received the option(s) shall automatically expire; said option(s) may
(if more than one) only be exercised consecutively;

         (ii) The provisions of paragraph 39, including the provision relating
to default of Lessee set forth in paragraph 39.4 of this Lease are conditions of
this Option;

         (iii) All of the terms and conditions of this Lease except where
specifically modified by this option shall apply;

         (iv) The monthly rent for each month of the option period shall be
calculated as follows, using the method(s) indicated below:

(x in box) III.   Fixed Rental Adjustment(s) (FRA)

The monthly rent payable under paragraph 1.5 ("Base Rent") of the attached Lease
shall be increased to the following amounts on the dates set forth below:

On (Fill in FRA Adjustment Date(s)):        The New Base Rental shall be:
March 1, 2000 - February 28, 2003           $12,075 per month

B. NOTICE: Unless specified otherwise herein, notice of any escalations other
than Fixed Rental Adjustments shall be made as specified in paragraph 23 of the
attached Lease.

C. BROKER'S FEE:

         The Real Estate Brokers specified in paragraph 1.10 of the attached
         Lease shall be paid a Brokerage Fee for each adjustment specified above
         in accordance with paragraph 15 of the attached Lease.

Initials: /s/RBG                                           Initials: /s/DBR

                               OPTION(S) TO EXTEND
                                   Page 1 of 2
<PAGE>
                                   EXHIBIT "A"

Map of property at corner of Seventeenth Street and Colorado Avenue showing R&D
Space






                   AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION
                                   AIR (LOGO)

1. Parties. This Lease, dated, for reference purposes only. October 12, 1992, is
made by and between VIRGINIA MERRITT, as Trustee of the Bowman Merritt and
Virginia Merritt Trust, (herein called "Lessor") and XOMA CORPORATION (herein
called "Lessee").

2. Premises. Lessor hereby leases to Lessee and Lessee leases from Lessor for
the term, at the rental, and upon all of the conditions set forth herein, that
certain real property situated in the County of Los Angeles State of California,
commonly known as 1545 17th Street, Santa Monica, California and described as
Approximately 18,000 sq. ft., building on site, more specifically described as
Lots O and P, Block 182, Town of Santa Monica, as recorded in Miscellaneous
Records, Book 39, Page 45, et seq., in the Office of the County Recorder of Los
Angeles County, California. Said real property including the land and all
improvements therein, is herein called "the Premises".

3.  Term.

         3.1 Term. The term of this Lease shall be for Five (5) years commencing
on October 12, 1992 and ending on October 12, 1997 unless sooner terminated
pursuant to any provision hereof.

         3.2 Delay in Possession. Not withstanding said commencement date, if
for any reason Lessor cannot deliver possession of the Premises to Lessee on
said date, Lessor shall not be subject to any liability therefor, nor shall such
failure affect the validity of this Lease or the obligations of Lessee hereunder
or extend the term hereof, but in such case, Lessee shall not be obligated to
pay rent until possession of the Premises is tendered to Lessee; provided,
however, that if Lessor shall not have delivered possession of the Premises
within sixty (60) days from said commencement date, Lessee may, at Lessee's
option, by notice in writing to Lessor within ten (10) days thereafter, cancel
this Lease, in which event the parties shall be discharged from all obligations
hereunder; provided further, however, that if such written notice of Lessee is
not received by Lessor within said ten (10) day period, Lessee's right to cancel
this Lease hereunder shall terminate and be of no further force or effect.

         3.3 Early Possession. If Lessee occupies the Premises prior to said
commencement date, such occupancy shall be subject to all provisions hereof,
such occupancy shall not advance the termination date, and Lessee shall pay rent
for such period at the initial monthly rates set forth below.

4.  Rent:  Special Net Lease.

         4.1 Rent. Lessee shall pay to Lessor as rent for the Premises, monthly
payments of $18,000.00, in advance, on the first day of each month of the term
hereof. Lessee shall pay Lessor upon the execution hereof $18,000.00 as rent for
the month of (See Addendum). Rent for any period during the term hereof which is
for less than one month shall be a pro rata portion of the monthly installment.
Rent shall be payable in lawful money of the United States to Lessor at the
address stated herein or to such other persons or at such other places as Lessor
may designate in writing.

         4.2 Special Net Lease. This Lease is what is commonly called a "Net,
Net, Net Lease", it being understood that the Lessor shall receive the rent set
forth in Paragraph 4.1 free and clear of any and all other impositions, taxes,
liens, charges or expenses of any nature whatsoever in connection with the
ownership and operation of the Premises. In addition to the rent reserved by
Paragraph 4.1, Lessee shall pay to the parties respectively entitled thereto all
impositions, insurance premiums, operating charges, maintenance charges,
construction costs, and any other charges, costs and expenses which arise or may
be contemplated under any provisions of this Lease during the term hereof. All
of such charges, costs and expenses shall constitute additional rent, and upon
the failure of Lessee to pay any of such costs, charges or expenses, Lessor
shall have the same rights and remedies as otherwise provided in this Lease for
the failure of Lessee to pay rent. It is the intention of the parties hereto
that Lessee shall in no event be entitled to any abatement of or reduction in
rent payable under this Lease, except as herein expressly provided. Any present
or future law to the contrary shall not alter this agreement of the parties.

5. Security Deposit. Lessee shall deposit with Lessor upon execution hereof
$25,144.00 (See Addendum) as security for Lessee's faithful performance of
Lessee's obligations hereunder. If Lessee fails to pay rent or other charges due
hereunder, or otherwise defaults with respect to any provision of this Lease,
Lessor may use, apply or retain all or any portion of said deposit for the
payment of any rent or other charge in default or for the payment of any other
sum to which Lessor may become obligated by reason of Lessee's default, or to
compensate Lessor for any loss or damage which Lessor may suffer thereby. If
Lessor so uses or applies all or any portion of said deposit, Lessee shall
within ten (10) days after written demand therefor deposit cash with Lessor in
an amount sufficient to restore said deposit to the full amount hereinabove
stated and Lessee's failure to do so shall be a material breach of this Lease.
Lessor shall not be required to keep said deposit separate from its general
accounts. If Lessee performs all of Lessee's obligations hereunder, said
deposit, or so much thereof as has not theretofore been applied by Lessor, shall
be returned, without payment of interest or other increment for its use, to
Lessee (or, at Lessor's option, to that last assignee, if any, of Lessee's
interest hereunder) at the expiration of the term hereof, and after Lessee has
vacated the Premises. No trust relationship is created herein between Lessor and
Lessee with respect to said Security Deposit.

6.  Use.

         6.1 Use. The Premises shall be used and occupied only for light
manufacturing, research laboratories, and office or any other use which is
reasonably comparable and for no other purpose.

         6.2  Compliance with Law.

                  (a) Lessor warrants to Lessee that the Premises, in its state
existing on the date that the Lease term commences, but without regard to the
use for which Lessee will use the Premises, does not violate any covenants or
restrictions of record, or any applicable building code, regulation or ordinance
in effect on such Lease term commencement date. In the event it is determined
that this warranty has been violated, then it shall be the obligation of the
Lessor, after written notice from Lessee, to promptly, at Lessor's sole cost and
expense, rectify any such violation. In the event Lessee does not give to Lessor
written notice of the violation of this warranty within six months from the date
that the Lease term commences, the correction of same shall be the obligation of
the Lessee at Lessee's sole cost. The warranty contained in this paragraph 6.2
(a) shall be of no force or effect if, prior to the date of this Lease, Lessee
was the owner or occupant of the Premises, and, in such event, Lessee shall
correct any such violation at Lessee's sole cost.

                  (b) Except as provided in paragraph 6.2(a), Lessee shall, at
Lessee's expense, comply promptly with all applicable statutes, ordinances,
rules, regulations, orders, covenants and restrictions of record, and
requirements in effect during the term or any part of the term hereof,
regulating the use by Lessee of the Premises. Lessee shall not use nor permit
the use of the Premises in any manner that will tend to create waste or a
nuisance or, if there shall be more than one tenant in the building containing
the Premises, shall tend to disturb such other tenants.

         6.3  Condition of Premises

                  (a) Lessor shall deliver the Premises to Lessee clean and free
of debris on Lease commencement date (unless Lessee is already in possession)
and Lessor further warrants to Lessee that the plumbing, lighting, air
conditioning, heating, and loading doors in the Premises shall be in good
operating condition on the Lease commencement date. In the event that it is
determined that this warranty has been violated, then it shall be the obligation
of Lessor, after receipt of written notice from Lessee setting forth with
specificity the nature of the violation, to promptly, at Lessor's sole cost,
rectify such violation. Lessee's failure to give such written notice to Lessor
within thirty (30) days after the Lease commencement date shall cause the
conclusive presumption that Lessor has complied with all of Lessor's obligations
hereunder. The warranty contained in this paragraph 6.3(a) shall be of no force
or effect if prior to the date of this Lease, Lessee was the owner or occupant
of the Premises.

                  (b) Except as otherwise provided in this Lease, Lessee hereby
accepts the Premises in their condition existing as of the Lease commencement
date or the date that Lessee takes possession of the Premises, whichever is
earlier, subject to all applicable zoning, municipal, county and state laws,
ordinances and regulations governing and regulating the use of the Premises, and
any covenants or restrictions of record, and accepts this Lease subject thereto
and to all matters disclosed thereby and by any exhibits attached hereto. Lessee
acknowledges that neither Lessor nor Lessor's agent has made any representation
or warranty as to the present or future suitability of the Premises for the
conduct of Lessee's business.

                                   SPECIAL NET

(This is a special form containing unique provisions and should only be used in
special situations where the LESSEE will pay rent under all circumstances and in
the event of destruction the LESSEE will rebuild under all circumstances.)
<PAGE>
7.  Maintenance, Repairs and Alterations.

         7.1 Lessee's Obligations. Lessee shall keep in good order, condition
and repair the Premises and every part thereof, structural and non structural,
(whether or not such portion of the Premises requiring repair, or the means of
repairing the same are reasonably or readily accessible to Lessee, and as a
result of Lessee's use, the elements or the age of such portion of the Premises)
including, without limiting the generality of the foregoing, all plumbing,
heating, air conditioning, (Lessee shall procure and maintain, at Lessee's
expense, an air conditioning system maintenance contract) ventilating,
electrical, lighting facilities and equipment within the Premises, fixtures,
walls (interior and exterior), foundations, ceilings, roofs (interior and
exterior), floors, windows, doors, plate glass and skylights located within the
Premises, and all landscaping, driveways, parking lots, fences and signs located
on the Premises and sidewalks and parkways adjacent to the Premises.

         7.2 Surrender. On the last day of the term hereof, or on any sooner
termination, Lessee shall surrender the Premises to Lessor in the same condition
as when received, ordinary wear and tear excepted, clean and free of debris.
Lessee shall repair any damage to the Premises occasioned by the installation or
removal of Lessee's trade fixtures, furnishings and equipment. Notwithstanding
anything to the contrary otherwise stated in this Lease, Lessee shall leave the
air lines, power panels, electrical distribution systems, lighting fixtures,
space heaters, air conditioning, plumbing and fencing on the premises in good
operating condition.

         7.3 Lessor's Rights. If Lessee fails to perform Lessee's obligations
under this Paragraph 7, or under any other paragraph of this Lease, Lessor may
at its option (but shall not be required to) enter upon the Premises after ten
(10) days' prior written notice to Lessee (except in the case of an emergency,
in which case no notice shall be required), perform such obligations on Lessee's
behalf and put the same in good order, condition and repair, and the cost
thereof together with the interest thereon at the maximum rate than allowable by
law shall become due and payable as additional rental to Lessor together with
Lessee's next rental installment.

         7.4 Lessor's Obligations. Except for the obligations of Lessor under
Paragraph 6.2(a) and 6.3(a)(relating to Lessor's warranty), Paragraph 9
(relating to destruction of the Premises, and under Paragraph 14 (relating to
condemnation of the Premises), it is intended by the parties hereto that Lessor
have no obligation, in any manner whatsoever, to repair and maintain the
Premises nor the building located thereon nor the equipment therein, whether
structural or non structural, all of which obligations are intended to be that
of the Lessee under Paragraph 7.1 hereof. Lessee expressly waives the benefit of
any statute now or hereinafter in effect which would otherwise afford Lessee the
right to make repairs at Lessor's expense or to terminate this Lease because of
Lessor's failure to keep the premises in good order, condition and repair.

         7.5  Alterations and Additions

                  (a) Lessee shall not, without Lessor's prior written consent
make any alterations, improvements, additions, or Utility installations in, on
or about the Premises, except for nonstructural alterations not exceeding
$50,000.00 in cumulative costs during the term of this Lease. In any event,
whether or not in excess of $50,000.00 in cumulative cost, Lessee shall make no
change or alteration to the exterior of the Premises nor the exterior of the
building(s) on the Premises without Lessor's prior written consent. As used in
this Paragraph 7.5 the term "Utility Installation" shall mean carpeting, window
coverings, air lines, power panels, electrical distribution systems, lighting
fixtures, space heaters, air conditioning, plumbing, and fencing. Lessor may
require that Lessee remove any or all of said alterations, improvements,
additions or Utility Installations at the expiration of the term, and restore
the Premises to their prior condition. Lessor may require Lessee to provide
Lessor, at Lessee's sole cost and expense, a lien and completion bond in an
amount equal to one times the estimated cost of such improvements, to insure
Lessor against any liability for mechanic's and materialmen's liens and to
insure completion of the work. Should Lessee make any alterations, improvements,
additions or Utility Installations without the prior approval of Lessor, Lessor
may require that Lessee remove any or all of the same.

         (b) Any alterations, improvements, additions or Utility Installations
in, or about the Premises that Lessee shall desire to make and which requires
the consent of the Lessor shall be presented to Lessor in written form, with
proposed detailed plans. If Lessor shall give its consent, the consent shall be
deemed conditioned upon Lessee acquiring a permit to do so from appropriate
governmental agencies, the furnishing of a copy thereof to Lessor prior to the
commencement of the work and the compliance by Lessee of all conditions of said
permit in a prompt and expeditious manner.

         (c) Lessee shall pay, when due, all claims for labor or materials
furnished or alleged to have been furnished to or for Lessee at or for use in
the Premises, which claims are or may be secured by any mechanics' or
materialmen's lien against the Premises or any interest therein. Lessee shall
give Lessor not less than ten (10) days' notice prior to the commencement of any
work in the Premises, and Lessor shall have the right to post notices of
non-responsibility in or on the Premises as provided by law. If Lessee shall, in
good faith, contest the validity of any such lien, claim or demand, then Lessee
shall, at its sole expense defend itself and Lessor against the same and shall
pay and satisfy any such adverse judgment that may be rendered thereon before
the enforcement thereof against the Lessor or the Premises, upon the condition
that if Lessor shall require, Lessee shall furnish to Lessor a surety bond
satisfactory to Lessor in an amount equal to such contested lien claim or demand
indemnifying Lessor against liability for the same and holding the Premises free
from the effect of such lien or claim. In addition, Lessor may require Lessee to
pay Lessor's attorneys fees and costs in participating in such action if Lessor
shall decide it is to its best interest to do so.

         (d) Unless Lessor requires their removal, as set forth in Paragraph
7.5(a), all alterations, improvements, additions and Utility Installations
(whether or not such Utility Installations constitute trade fixtures of Lessee),
which may be made on the Premises, shall become the property of Lessor and
remain upon and be surrendered with the Premises at the expiration of the term.
Notwithstanding the provisions of this Paragraph 7.5(d), Lessee's machinery and
equipment, other than that which is affixed to the Premises so that it cannot be
removed without material damage to the Premises(which cannot thereby be restored
to their original condition, normal wear and tear excepted), shall remain the
property of Lessee and may be removed by Lessee subject to the provisions of
Paragraph 7.2.

8.  Insurance Indemnity.

         8.1 Insuring Party. As used in this Paragraph 8, the term "insuring
party" shall mean the party who has the obligation to obtain the Property
Insurance required hereunder. The insuring party shall be designated in
Paragraph 46 hereof. In the event Lessor is the insuring party, Lessor shall
also maintain the liability insurance described in paragraph 8.2 hereof, in
addition to, and not in lieu of, the insurance required to be maintained by
Lessee under said paragraph 8.2, but Lessor shall not be required to name Lessee
as an additional insured on such policy. Whether the insuring party is the
Lessor or the Lessee, Lessee shall, as additional rent for the Premises, pay the
cost of all insurance required hereunder, except for that portion of the cost
attributable to Lessor's liability insurance coverage in excess of $1,000,000
per occurrence. If Lessor is the insuring party Lessee shall, within ten (10)
days following demand by Lessor, reimburse Lessor for the cost of the insurance
so obtained.

         8.2 Liability Insurance. Lessee shall, at Lessee's expense obtain and
keep in force during the term of this Lease a policy of Combined Single Limit,
Bodily Injury and Property Damage insurance insuring Lessor and Lessee against
any liability arising out of the ownership, use, occupancy or maintenance of the
Premises and all areas appurtenant thereto. Such insurance shall be a combined
single limit policy in an amount not less than $500,000 per occurrence. The
policy shall insure performance by Lessee of the indemnity provisions of this
Paragraph 8. The limits of said insurance shall not, however, limit the
liability of Lessee hereunder.

         8.3  Property Insurance.

                  (a) The insuring party shall obtain and keep in force during
the term of this Lease a policy or policies of insurance covering loss or damage
to the Premises, in the amount of the full replacement value thereof, as the
same may exist from time to time, which replacement value is now $1.4 million,
but in no event less than the total amount required by lenders having liens on
the Premises, against all perils included within the classification of fire,
extended coverage, vandalism, malicious mischief, flood (in the event same is
required by a lender having a lien on the Premises), and special extended perils
("all risk" as such term is used in the insurance industry). Said insurance
shall provide for payment of loss thereunder to Lessor or to the holders of
mortgages or deeds of trust on the Premises. The insuring party shall, in
addition, obtain and keep in force during the term of this Lease a policy of
rental value insurance covering a period of one year, with loss payable to
Lessee, which insurance shall also cover all real estate taxes and insurance
costs for said period. A replacement value endorsement deleting the coinsurance
provision of the policy shall be procured with said insurance as well as an
automatic increase in insurance endorsement causing the increase in annual
property insurance coverage. If the insuring party shall fail to procure and
maintain said insurance the other party may, but shall not be required to,
procure and maintain the same, but at the expense of Lessee. If such insurance
coverage has a deductible clause, the deductible amount shall not exceed
$5,000.00 per occurrence, and Lessee shall be liable for such deductible amount.

                  (b) If the Premises are part of a larger building, or if the
Premises are part of a group of buildings owned by Lessor which are adjacent to
the Premises, then Lessee shall pay for any increase in the property insurance
of such other building or buildings if said increase is caused by Lessee's acts,
omissions, use or occupancy of the Premises.

                  (c) If the Lessor is the insuring party the Lessor will not
insure Lessee's fixtures, equipment or tenant improvements unless the tenant
improvements have become a part of the Premises under paragraph 7, hereof. But
if Lessee is the insuring party the Lessee shall insure its fixtures, equipment
and tenant improvements.

         8.4 Insurance Policies. Insurance required hereunder shall be in
companies holding a "General Policyholders Rating" of at least B plus, or such
other rating as may be required by a lender having a lien on the Premises, as
set forth in the most current issue of "Best's Insurance Guide". The insuring
party shall deliver to the other party copies of policies of such insurance or
certificates evidencing the existence and amounts of such insurance with loss
payable clauses as required by this paragraph 8. No such policy shall be
cancellable or subject to reduction of coverage or other modification except
after thirty (30) days' prior written notice to Lessor. If Lessee is the
insuring party Lessee shall, at least thirty (30) days prior to the expiration
of such policies, furnish Lessor with renewals or "binders" thereof, or Lessor
may order such insurance and charge the cost thereof to Lessee, which amount
shall be payable by Lessee upon demand. Lessee shall not do or permit to be done
anything which shall invalidate the insurance policies referred to in Paragraph
8.3. If Lessee does or permits to be done anything which shall increase the cost
of the insurance policies referred to in Paragraph 8.3, then Lessee shall
forthwith upon Lessor's demand reimburse Lessor for any additional premiums
attributable to any act or omission or operation of Lessee causing such increase
in the cost of insurance. If Lessor is the insuring party, and if the insurance
policies maintained hereunder cover other improvements in addition to the
Premises, Lessor shall deliver to Lessee a written statement setting forth the
amount of any such insurance cost increase and showing in reasonable detail the
manner in which it has been computed.

         8.5 Waiver of Subrogation. Lessee and Lessor each hereby release and
relieve the other, and waive their entire right of recovery against the other
for loss or damage arising out of or incident to the perils insured against
under paragraph 8.3, which perils occur in, on or about the Premises, whether
due to the negligence of Lessor or Lessee or their agents, employees,
contractors and/or invitees. Lessee and Lessor shall, upon obtaining the
policies of insurance required hereunder, give notice to the insurance carrier
or carriers that the foregoing mutual waiver of subrogation is contained in this
Lease.

         8.6 Indemnity. Lessee shall indemnify and hold harmless Lessor from and
against any and all claims arising from Lessee's use of the Premises, or from
the conduct of Lessee's business or from any activity, work or things done,
permitted or suffered by Lessee in or about the Premises or elsewhere and shall
further indemnify and hold harmless Lessor from and against any and all claims
arising from any breach or default

                                       -2-
<PAGE>
in the performance of any obligation on Lessee's part to be performed under the
terms of this Lease, or arising from any negligence of the Lessee, or any of
Lessee's agents, contractors, or employees, and from and against all costs,
attorney's fees, expenses and liabilities incurred in the defense of any such
claim or any action or proceeding brought thereon; and in case any action or
proceeding be brought against Lessor by reason of any such claim, Lessee upon
notice from Lessor shall defend the same at Lessee's expense by counsel
satisfactory to Lessor. Lessee, as a material part of the consideration to
Lessor, hereby assumes all risk of damage to property or injury to persons, in,
upon or about the Premises arising from any cause and Lessee hereby waives all
claims in respect thereof against Lessor.

         8.7 Exemption of Lessor from Liability. Lessee hereby agrees that
Lessor shall not be liable for injury to Lessee's business or any loss of income
therefrom or for damage to the goods, wares, merchandise or other property of
Lessee, Lessee's employees, invitees, customers, or another person in or about
the Premises, nor shall Lessor be liable for injury to the person of Lessee,
Lessee's employees, agents or contractors whether such damage or injury is
caused by or results from fire, steam, electricity, gas, water or rain, or from
the breakage, leakage, obstruction or other defects of pipes, sprinklers, wires,
appliances, plumbing, air conditioning or lighting fixtures, or from any other
cause, except for Lessor's negligence or breach of an express warranty contained
in this Lease, whether the said damage or injury results from conditions arising
upon the Premises or upon other portions of the building of which the Premises
are a part, or from other sources or places and regardless of whether the cause
of such damage or injury or the means of repairing the same is inaccessible to
Lessee. Lessor shall not be liable for any damages arising from any act or
neglect of any other tenant, if any, of the building in which the Premises are
located.

9. Damage, Destruction, Obligation to Rebuild, Rent Abatement.

         9.1 Obligation to Rebuild. In the event that some or all of the
improvements constituting a part of the Premises or the Premises itself are
damaged or destroyed, partially or totally from any cause other than the acts or
omissions to act of Lessor, whether or not such damage or destruction is covered
by any insurance required to be maintained under Paragraph 8.3 hereof, then
Lessee shall repair, restore and rebuild the Premises to its condition existing
immediately prior to such damage or destruction and this Lease shall remain in
full force and effect. Such repair, restoration and rebuilding (all of which are
herein called "repair") shall be commenced within a reasonable time after such
damage or destruction has occurred and shall be diligently pursued to
completion, provided the damage or destruction was not caused by Lessor.

         9.2 Insurance Proceeds. The proceeds of any insurance maintained under
Paragraph 8.3 hereof shall be made available to Lessee for payment of costs and
expense of repair, provided however, that such proceeds may be made available to
Lessee subject to reasonable condition including, but not limited to architect's
certification of cost, retention of percentage of such proceeds pending
recordation of a notice of completion and a lien and completion bond to insure
against mechanic's or materialmen's liens arising out of the repair and to
insure completion of the repair all at the expense of Lessee. In the event the
insurance proceeds are insufficient to cover the cost of repair, then any
amounts required over the amount of the insurance proceeds received that are
required to complete said repair shall be paid by Lessee. In the event the
insurance proceeds are not made available to Lessee within 120 days after such
damage or destruction, Lessee shall have the option for 30 days commencing on
the expiration of such 120 day period, of cancelling this Lease. If Lessee shall
exercise such option, Lessee shall have no further obligation hereunder and
shall have no claim against Lessor. Lessee, in order to exercise said option,
shall exercise said option by giving written notice to Lessor within said 30 day
period, time being of the essence.

         9.3  Damage Near End of Term

                  (a) If the Premises are damaged or destroyed, either partially
or totally, during the last six months of the term of this Lease, Lessor may at
Lessor's option cancel and terminate this Lease as of the date of occurrence of
such damage by giving written notice to Lessee of Lessor's election to do so
within 30 days after the date of occurrence of such damage.

                  (b) Notwithstanding paragraph 9.3(a) to the contrary, in the
event that Lessee has an option to extend or renew this Lease, and the time
within which said option may be exercised has not yet expired, Lessee shall
exercise such option, if it is to be exercised at all, no later than 20 days
after damage or destruction to the Premises, either total or partial occurring
during the last six months of the term of this Lease, which damage or
destruction is covered by insurance required to be maintained under paragraph 8.
If Lessee duly exercises such option during said 20 day period Lessee shall, in
accordance with paragraph 9.2, at Lessee's expense, repair such damage as soon
as reasonably possible and this Lease shall continue in full force and effect.
If Lessee fails to exercise such option during said 20 day period, then Lessor
may at Lessor's option terminate and cancel this Lease as of the expiration of
said 20 day period by giving written notice to Lessee of Lessor's election to do
so within 10 days after the expiration of said 20 day period, notwithstanding
any term or provision in the grant of option to the contrary.

         9.4 Abatement of Rent. Notwithstanding the partial or total destruction
of the Premises and any part thereof, and notwithstanding whether the casualty
is insured or not, there shall be no abatement of rent or of any other
obligation of Lessee hereunder by reason of such damage or destruction unless
the Lease is terminated by virtue of any other provision of this Lease.

         9.5 Termination - Advance Payments. Upon termination of this Lease
pursuant to this Paragraph 9, an equitable adjustment shall be made concerning
advance rent and any payments made by Lessee to Lessor. Lessor shall, in
addition, return to Lessee so much of Lessee's security deposit as has not
theretofore been applied by Lessor.

         9.6 Waiver. Lessee waives the provisions of any statutes which relate
to termination of leases when the thing leased is destroyed and agrees that such
event shall be governed by the terms of this Lease.

10.  Real Property Taxes.

         10.1 Payment of Taxes. Lessee shall pay the real property tax, as
defined in paragraph 10.2, applicable to the Premises during the term of this
Lease. All such payments shall be made at least ten (10) days prior to the
delinquency date of such payment. Lessee shall promptly furnish Lessor with
satisfactory evidence that such taxes have been paid. If any such taxes paid by
Lessee shall cover any period of time prior to or after the expiration of the
term hereof, Lessee's share of such taxes shall be equitably prorated to cover
only the period of time within the tax fiscal year during which this Lease shall
be in effect, and Lessor shall reimburse Lessee to the extent required. If
Lessee shall fail to pay any such taxes, Lessor shall have the right to pay the
same, in which case Lessee shall repay such amount to Lessor with Lessee's next
rent installment together with interest at the maximum rate then allowable by
law.

         10.2 Definition of "Real Property Tax". As used herein, the term "real
property tax" shall include any form of real estate tax or assessment general,
special, ordinary or extraordinary, and any license fee, commercial rental tax,
improvement bond or bonds, levy or tax (other than inheritance, personal income
or estate taxes) imposed on the Premises by any authority having the direct or
indirect power to tax, including any city, state or federal government, or any
school, agricultural, sanitary, fire, street, drainage or other improvement
district thereof, as against any legal or equitable interest of Lessor in the
Premises or in the real property of which the Premises are a part, as against
Lessor's right to rent or other income therefrom, and as against Lessor's
business of leasing the Premises. The term "real property tax" shall also
include any tax, fee, levy, assessment or charge (i) in substitution of,
partially or totally, any tax, fee, levy, assessment or charge hereinabove
included within the definition of "real property tax," or (ii) the nature of
which was hereinbefore included within the definition of "real property tax," or
(iii) which is imposed for a service or right not charged prior to June 1, 1978,
or, if previously charged, has been increased since June 1, 1978, or (v) which
is imposed by reason of this transaction, any modifications or changes heretofor
any transfers hereof.

         10.3 Joint Assessment. If the Premises are not separately assessed,
Lessee's liability shall be equitable proportion of the real property taxes for
all of the land and improvement included within the tax parcel assessed, such
proportion to be determined by Lessor from the respective valuations assigned in
the assessor's work sheets or such other information as may be reasonably
available. Lessor's reasonable determination thereof, in good faith, shall be
conclusive.

         10.4  Personal Property Taxes.

                  (a) Lessee shall pay prior to delinquency all taxes assessed
against and levied upon trade fixtures, furnishings, equipment and all other
personal property of Lessee contained in the Premises or elsewhere. When
possible, Lessee shall cause said trade fixtures, furnishings, equipment and all
other personal property to be assessed and billed separately from the real
property of Lessor.

                  (b) If any of Lessee's said personal property shall be
assessed with Lessor's real property, Lessee shall pay Lessor the taxes
attributable to Lessee within 10 days after receipt of a written statement
setting forth the taxes applicable to Lessee's property.

11. Utilities. Lessee shall pay for all water, gas, heat, light, power,
telephone and other utilities and services supplied to the Premises, together
with any taxes thereon. If any such services are not separately metered to
Lessee, Lessee shall pay a reasonable proportion to be determined by Lessor of
all charges jointly metered with other premises.

12.  Assignment and Subletting.

         12.1 Lessor's Consent Required. Lessee shall not voluntarily or by
operation of law assign, transfer, mortgage, sublet, or otherwise transfer or
encumber all or any part of Lessee's interest in this Lease or in the Premises,
without Lessor's prior written consent, which Lessor shall not unreasonably
withhold. Lessor shall respond to Lessee's request for consent hereunder in a
timely manner and any attempted assignment, transfer, mortgage, encumbrance or
subletting without such consent shall be void, and shall constitute a breach of
this Lease.

         12.2 Lessee Affiliate. Notwithstanding the provisions of paragraph 12.1
hereof, Lessee may assign or sublet the Premises, or any portion thereof,
without Lessor's consent, to any corporation which controls, is controlled by or
is under common control with Lessee, or to any corporation resulting from the
merger or consolidation with Lessee, or to any person or entity which acquires
all the assets of Lessee as a going concern of the business that is being
conducted on the Premises, provided that said assignee assumes, in full, the
obligations of Lessee under this Lease. Any such assignment shall not, in any
way, affect or limit the liability of Lessee under the terms of this Lease even
if after such assignment or subletting the terms of this Lease are materially
changed or altered without the consent of Lessee, the consent of whom shall not
be necessary.

         12.3 No Release of Lessee. Regardless of Lessor's consent, no
subletting or assignment shall release Lessee of Lessee's obligation or alter
the primary liability of Lessee to pay the rent and to perform all other
obligations to be performed by Lessee hereunder. The acceptance of rent by
Lessor from any other person shall not be deemed to be a waiver by Lessor of any
provision hereof. Consent to one assignment or subletting shall not be deemed
consent to any subsequent assignment or subletting. In the event of default by
any assignee of Lessee or any successor of Lessee, in the performance of any of
the terms hereof, Lessor may proceed directly against Lessee without the
necessity of exhausting remedies against said assignee. Lessor may consent to
subsequent assignments or subletting of this Lease or amendments or
modifications to this Lease with assignees of Lessee, without notifying Lessee,
or any successor of Lessee, and without obtaining its or their consent thereto
and such action shall not relieve Lessee of liability under this Lease.

         12.4 Attorney's Fees. In the event Lessee shall assign or sublet the
Premises or request the consent of Lessor to any assignment or subletting or if
Lessee shall request the consent of Lessor for any act Lessee proposes to do
then Lessee shall pay Lessor's reasonable attorneys fees incurred in connection
therewith, such attorneys fees not to exceed $350.00 for each request.

                                       -3-
<PAGE>
13.  Defaults; Remedies.

         13.1 Defaults. The occurrence of any one or more of the following
events shall constitute a material default and breach of this Lease by Lessee:

                  (a)  The vacating or abandonment of the Premises by Lessee.

                  (b) The failure by Lessee to make any payment of rent or any
other payment required to be made by Lessee hereunder, as and when due, where
such failure shall continue for a period of three days after written notice
thereof from Lessor to Lessee. In the event that Lessor serves Lessee with a
Notice to Pay Rent or Quit pursuant to applicable Unlawful Detainer statutes
such Notice to Pay Rent or Quit shall also constitute the notice required by
this subparagraph.

                  (c) The failure by Lessee to observe or perform any of the
covenants, conditions or provisions of this Lease to be observed or performed by
Lessee, other than described in paragraph (b) above, where such failure shall
continue for a period of 30 days after written notice thereof from Lessor to
Lessee; provided, however, that if the nature of Lessee's default is such that
more than 30 days are reasonably required for its cure, then Lessee shall not be
deemed to be in default if Lessee commenced such cure within said 30-day period
and thereafter diligently prosecutes such cure to completion.

                  (d) (i) The making by Lessee of any general arrangement or
assignment for the benefit of creditors; (ii) Lessee becomes a "debtor" as
defined in 11 U.S.C. &101 or any successor statute thereto (unless, in the case
of a petition filed against Lessee, the same is dismissed within 60 days); (iii)
the appointment of a trustee or receiver to take possession of substantially all
of Lessee's assets located at the Premises or of Lessee's interest in this
Lease, where possession is not restored to Lessee within 30 days; or (iv) the
attachment, execution or other judicial seizure of substantially all of Lessee's
assets located at the Premises or of Lessee's interest in this Lease, where such
seizure is not discharged within 30 days. Provided, however, in the event that
any provision of this paragraph 13.1(d) is contrary to any applicable law, such
provision shall be of no force or effect.

                  (e) The discovery by Lessor that any financial statement given
to Lessor by Lessee, any assignee of Lessee, any subtenant of Lessee, any
successor in interest of Lessee or any guarantor of Lessee's obligation
hereunder, and any of them, was materially false.

         13.2 Remedies. In the event of any such material default or breach by
Lessee, Lessor may at any time thereafter, with or without notice or demand and
without limiting Lessor in the exercise of any right or remedy which Lessor may
have by reason of such default or breach:

                  (a) Terminate Lessee's right to possession of the Premises by
any lawful means, in which case this Lease shall terminate and Lessee shall
immediately surrender possession of the Premises to Lessor. In such event Lessor
shall be entitled to recover from Lessee all damages incurred by Lessor by
reason of Lessee's default including, but not limited to, the cost of recovering
possession of the Premises; expenses of reletting, including necessary
renovation and alteration of the Premises, reasonable attorney's fees, and any
real estate commission actually paid; the worth at the time of award by the
court having jurisdiction thereof of the amount by which the unpaid rent for the
balance of the term after the time of such award exceeds the amount of such
rental loss for the same period that Lessee proves could be reasonably avoided;
that portion of the leasing commission paid by Lessor pursuant to Paragraph 15
applicable to the unexpired term of this Lease.

                  (b) Maintain Lessee's right to possession in which case this
Lease shall continue in effect whether or not Lessee shall have abandoned the
Premises. In such event Lessor shall be entitled to enforce all of Lessor's
rights and remedies under this Lease, including the right to recover the rent as
it becomes due hereunder.

                  (c) Pursue any other remedy now or hereafter available to
Lessor under the laws or judicial decisions of the state wherein the Premises
are located. Unpaid installments of rent and other unpaid monetary obligations
of Lessee under the terms of this Lease shall bear interest from the date due at
the maximum rate then allowable by law.

         13.3 Default by Lessor. Lessor shall not be in default unless Lessor
fails to perform obligations required of Lessor within a reasonable time, but in
no event later than thirty (30) days after written notice by Lessee to Lessor
and to the holder of any first mortgage or deed of trust covering the Premises
whose name and address shall have theretofore been furnished to Lessee in
writing, specifying wherein Lessor has failed to perform such obligation;
provided, however, that if the nature of Lessor's obligation is such that more
than thirty (30) days are required for performance then Lessor shall not be in
default if Lessor commences performance within such 30-day period and thereafter
diligently prosecutes the same to completion.

         13.4 Late Charges. Lessee hereby acknowledges that late payment by
Lessee to Lessor of rent and other sums due hereunder will cause Lessor to incur
costs not contemplated by this Lease, the exact amount of which will be
extremely difficult to ascertain. Such costs include, but are not limited to,
processing and accounting charges, and late charges which may be imposed on
Lessor by the terms of any mortgage or trust deed covering the Premises.
Accordingly, if any installment of rent or any other sum due from Lessee shall
not be received by Lessor or Lessor's designee within ten (10) days after such
amount shall be due, then, without any requirement for notice to Lessee, Lessee
shall pay to Lessor a late charge equal to 6% of such overdue amount. The
parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Lessor will incur by reason of late payment by Lessee.
Acceptance of such late charge by Lessor shall in no event constitute a waiver
of Lessee's default with respect to such overdue amount, nor prevent Lessor from
exercising any of the other rights and remedies granted hereunder. In the event
that a late charge is payable hereunder, whether or not collected, for three (3)
consecutive installments of rent, then rent shall automatically become due and
payable quarterly in advance, rather than monthly, notwithstanding paragraph 4
or any other provision of this Lease to the contrary.

         13.5 Impounds. In the event that a late charge is payable hereunder,
whether or not collected, for three (3) installments of rent or any other
monetary obligation of Lessee under the terms of this Lease, Lessee shall pay to
Lessor, if Lessor shall so request, in addition to any other payments required
under this Lease, a monthly advance installment, payable at the same time as the
monthly rent, as estimated by Lessor, for real property tax and insurance
expenses on the Premises which are payable by Lessee under the terms of this
Lease. Such fund shall be established to insure payment when due, before
delinquency, of any or all such real property taxes and insurance premiums. If
the amounts paid to Lessor by Lessee under the provisions of this paragraph are
insufficient to discharge the obligations of Lessee to pay such real property
taxes and insurance premiums as the same become due, Lessee shall pay to Lessor,
upon Lessor's demand such additional sums necessary to pay such obligations. All
moneys paid to Lessor under this paragraph may be intermingled with other moneys
of Lessor and shall not bear interest. In the event of a default in the
obligations of Lessee to perform under this Lease, then any balance remaining
from funds paid to Lessor under the provisions of this paragraph may, at the
option of Lessor, be applied to the payment of any monetary default of Lessee in
lieu of being applied to the payment of real property tax and insurance
premiums.

14. Condemnation. If the Premises or any portion thereof are taken under the
power of eminent domain, or sold under the threat of the exercise of said power
(all of which are herein called "condemnation"), this Lease shall terminate as
to the part so taken as of the date the condemning authority takes title or
possession, whichever first occurs. If more than 10% of the floor area of the
building on the Premises, or more than 25% of the land area of the Premises
which is not occupied by any building, is taken by condemnation, Lessee may, at
Lessee's option, to be exercised in writing only within ten (10) days after
Lessor shall have given Lessee written notice of such taking (or in the absence
of such notice, within ten (10) days after the condemning authority shall have
taken possession) terminate this Lease as of the date the condemning authority
takes such possession. If Lessee does not terminate this Lease in accordance
with the foregoing, this Lease shall remain in full force and effect as to the
portion of the Premises remaining, except that the rent shall be reduced in the
proportion that the floor area of the building taken bears to the total floor
area of the building situated on the Premises. No reduction of rent shall occur
if the only area taken is that which does not have a building located thereon.
Any award for the taking of all or any part of the Premises under the power of
eminent domain or any payment made under threat of the exercise of such power
shall be the property of Lessor, whether such award shall be made as
compensation for diminution in value of the leasehold or for the taking of the
fee, or as severance damages; provided, however, that Lessee shall be entitled
to any award for loss of or damage to Lessee's trade fixtures and removable
personal property. In the event that this Lease is not terminated by reason of
such condemnation, Lessor shall to the extent of severance damages received by
Lessor in connection with such condemnation, repair any damage to the Premises
caused by such condemnation except to the extent that Lessee has been reimbursed
therefor by the condemning authority. Lessee shall pay any amount in excess of
such severance damages required to complete such repair.

15.  (Deleted)

16.  Estoppel Certificate.

         (a) Lessee shall at any time upon not less than ten (10) days' prior
written notice from Lessor execute, acknowledge and deliver to Lessor a
statement in writing (i) certifying that this Lease is unmodified and in full
force and effect (or, if modified, stating the nature of such modification and
certifying that this Lease, as so modified, is in full force and effect) and the
date to which the rent and other charges are paid in advance, if any, and (ii)
acknowledging that there are not, to Lessee's knowledge, any uncured defaults on
the part of Lessor hereunder, or specifying such defaults if any are claimed.
Any such statement may be conclusively relied upon by any prospective purchaser
or encumbrancer of the Premises.

         (b) At Lessor's option, Lessee's failure to deliver such statement
within such time shall be a material breach of this Lease or shall be conclusive
upon Lessee (i) that this Lease is in full force and effect, without
modification except as may be represented by Lessor, (ii) that there are no
uncured defaults in Lessor's performance, and (iii) that not more than one
month's rent has been paid in advance or such failure may be considered by
Lessor as a default by Lessee under this Lease.

         (c) If Lessor desires to finance, refinance, or sell the Premises, or
any part thereof, Lessee agrees to deliver to any lender or purchaser designated
by Lessor such published financial statements of Lessee as may be reasonably
required by such lender or purchaser. Such statements shall include the past
three years' financial statements of Lessee. All such financial statements shall
be received by Lessor and such lender or purchaser in confidence and shall be
used only for the purposes herein set forth.

                                       -4-
<PAGE>
17. (Deleted)

18. Severability. The invalidity of any provision of this Lease as determined by
a court of competent jurisdiction, shall in no way affect the validity of any
other provision hereof.

19. Interest on Past-due Obligations. Except as expressly herein provided, any
amount due to Lessor not paid when due shall bear interest at the maximum rate
then allowable by law from the date due. Payment of such interest shall not
excuse or cure any default by Lessee under this Lease, provided, however, that
interest shall not be payable on late charges incurred by Lessee nor on any
amounts upon which late charges are paid by Lessee.

20. Time of Essence. Time is of the essence.

21. Additional Rent. Any monetary obligations of Lessee to Lessor under the
terms of this Lease shall be deemed to be rent.

22. Incorporation of Prior Agreements; Amendments. This Lease contains all
agreements of the parties with respect to any matter mentioned herein. No prior
agreement or understanding pertaining to any such matter shall be effective.
This Lease may be modified in writing only, signed by the parties in interest at
the time of the modification. Except as otherwise stated in this Lease, Lessee
hereby acknowledges that neither the real estate broker listed in Paragraph 15
hereof nor any cooperating broker on this transaction nor the Lessor or any
employees or agents of any of said persons has made any oral or written
warranties or representations to Lessee relative to the condition or use by
Lessee of said Premises and Lessee acknowledges that Lease assumes all
responsibility regarding the Occupational Safety Health Act, the legal use and
adaptability of the Premises and the compliance thereof with all applicable laws
and regulations in effect during the term of this Lease except as otherwise
specifically stated in this Lease.

23. Notices. Any notice required or permitted to be given hereunder shall be in
writing and may be given by personal delivery or by certified mail, and if given
personally or by mail, shall be deemed sufficiently given if addressed to Lessee
or to Lessor at the address noted below the signature of the respective parties,
as the case may be. Either party may by notice to the other specify a different
address for notice purposes except that upon Lessee's taking possession of the
Premises, the Premises shall constitute Lessee's address for notice purposes. A
copy of all notices required or permitted to be given to Lessor hereunder shall
be concurrently transmitted to such party or parties at such addresses as Lessor
may from time to time hereafter designate by notice to Lessee.

24. Waivers. No waiver by Lessor or any provision hereof shall be deemed a
waiver of any other provision hereof or of any subsequent breach by Lessee of
the same or any other provision. Lessor's consent to, or approval of, any act
shall not be deemed to render unnecessary the obtaining of Lessor's consent to
or approval of any subsequent act by Lessee. The acceptance of rent hereunder by
Lessor shall not be a waiver of any preceding breach by Lessee of any provision
hereof, other than the failure of Lessee to pay the particular rent so accepted,
regardless of Lessor's knowledge of such preceding breach at the time of
acceptance of such rent.

25. Recording. Either Lessor or Lessee shall, upon request of the other,
execute, acknowledge and deliver to the other a "short form" memorandum of this
Lease for recording purposes.

26. Holding Over. If Lessee, with Lessor's consent, remains in possession of the
Premises or any part thereof after the expiration of the term hereof, such
occupancy shall be a tenancy from month to month upon all the provisions of this
Lease pertaining to the obligations of Lessee, but all options and rights of
first refusal, if any, granted under the terms of this Lease shall be deemed
terminated and be of no further effect during said month to month tenancy.

27. Cumulative Remedies. No remedy or election hereunder shall be deemed
exclusive but shall, wherever possible, be cumulative with all other remedies at
law or in equity.

28. Covenants and Conditions. Each provision of this Lease performable by Lessee
shall be deemed both a covenant and a condition.

29. Binding Effect; Choice of Law. Subject to any provisions hereof restricting
assignment or subletting by Lessee and subject to the provisions of Paragraph
17, this Lease shall bind the parties, their personal representatives,
successors and assigns. This Lease shall be governed by the laws of the State
wherein the Premises are located.

30.  Subordination.

         (a) This Lease, at Lessor's option, shall be subordinate to any ground
lease, mortgage, deed of trust, or any other hypothecation or security now or
hereafter placed upon the real property of which the Premises are a part and to
any and all advances made on the security thereof and to all renewals,
modifications, consolidations, replacements and extensions thereof.
Notwithstanding such subordination; Lessee's right to quiet possession of the
Premises shall not be disturbed if Lessee is not in default and so long as
Lessee shall pay the rent and observe and perform all of the provisions of this
Lease, unless this Lease is otherwise terminated pursuant to its terms. If any
mortgage, trustee or ground lessor shall elect to have this Lease prior to the
lien of its mortgage, deed of trust or ground lease, and shall give written
notice thereof to Lessee, this Lease shall be deemed prior to such mortgage,
deed of trust, or ground lease, whether this Lease is dated prior or subsequent
to the date of said mortgage, deed of trust or ground lease or the date of
recording thereof.

         (b) Lessee agrees to execute any documents required to effectuate an
attornment, a subordination or to make this Lease prior to the lien of any
mortgage, deed of trust or ground lease, as the case may be. Lessee's failure to
execute such documents within 10 days after written demand shall constitute a
material default by Lessee hereunder, or, at Lessor's option, Lessor shall
execute such documents on behalf of Lessee as Lessee's attorney-in-fact. Lessee
does hereby make, constitute and irrevocably appoint Lessor as Lessee's
attorney-in-fact and in Lessee's name, place and stead, to execute such
documents in accordance with this paragraph 30(b).

31. Attorney's Fees. If either party or the broker named herein brings an action
to enforce the terms hereof or declare rights hereunder, the prevailing party in
any such action, on trial or appeal, shall be entitled to his reasonable
attorney's fees to be paid by the losing party as fixed by the court. The
provisions of this paragraph shall inure to the benefit of the broker named
herein who seeks to enforce a right hereunder.

32. Lessor's Access. Lessor and Lessor's agents shall have the right to enter
the Premises at reasonable times for the purpose of inspecting the same, showing
the same to prospective purchasers, lenders, or leases, and making such
alterations, repairs, improvements or additions to the Premises or to the
building of which they are a part as Lessor may deem necessary or desirable.
Lessor may at any time place on or about the Premises any ordinary "For Sale"
signs and Lessor may at any time during the last 120 days of the term hereof
place on or about the Premises any ordinary "For Lease" signs, all without
rebate of rent or liability to Lessee.

33. Auctions. Lessee shall not conduct, nor permit to be conducted, either
voluntarily or involuntarily, any auction upon the Premises without first having
obtained Lessor's prior written consent. Notwithstanding anything to the
contrary in this Lease, Lessor shall not be obligated to exercise any standard
of reasonableness in determining whether to grant such consent.

34. Signs. Lessee shall not place any sign upon the Premises without Lessor's
prior written consent except that Lessee shall have the right, without the prior
permission of Lessor to place ordinary and usual for rent or sublet signs
thereon.

35. Merger. The voluntary or other surrender of this Lease by Lessee, or a
mutual cancellation thereof, or a termination by Lessor, shall not work a
merger, and shall, at the option of Lessor, terminate all or any existing
subtenancies or may, at the option of Lessor, operate at an assignment to Lessor
of any or all of such subtenancies.

36. Consents. Except for paragraph 33 hereof, wherever in this Lease the consent
of one party is required to an act of the other party such consent shall not be
unreasonably withheld.

37. Guarantor. In the event that there is a guarantor of this Lease, said
guarantor shall have the same obligations as Lessee under this Lease.

38. Quiet Possession. Upon Lessee paying the rent for the Premises and observing
and performing all of the covenants, conditions and provisions on Lessee's part
to be observed and performed hereunder, Lessee shall have quiet possession of
the Premises for the entire term hereof subject to all of the provisions of this
Lease. The individuals executing this Lease on behalf of Lessor represent and
warrant to Lessee that they are fully authorized and legally capable of
executing this Lease on behalf of Lessor represent and warrant to Lessee that
they are fully authorized and legally capable of executing this Lease on behalf
of Lessor and that such execution is binding upon all parties holding an
ownership interest in the Premises.

39.  Options.

         39.1 Definition. As used in this paragraph the word "Options" has the
following meaning: (1) the right or option to extend the term of this Lease or
to renew this Lease or to extend or renew any lease that Lessee has on the other
property of Lessor; (2) the option or right of first refusal to lease the
Premises or the right of first offer to lease the Premises or the right of first
refusal to lease other property of Lessor or the right of first offer to lease
other property of Lessor; (3) the right or option to purchase the Premises, or
the right of first refusal to purchase the Premises, or the right of first offer
to purchase the Premises or the right or option to purchase other property of
Lessor, or the right of first refusal to purchase other property of Lessor or
the right of first offer to purchase other property of Lessor.

         39.2 Options Personal. Each Option granted to Lessee in this Lease are
personal to Lessee and may not be exercised or be assigned, voluntarily or
involuntarily, by or to any person or entity other than Lessee, provided,
however, the Option may be exercised by or assigned to any Lessee Affiliate as
defined in paragraph 12.2 of this Lease. The Options herein granted to Lessee
are not assignable separate and apart from this Lease.

         39.3 Multiple Options. In the event that Lessee has any multiple
options to extend or renew this Lease a later option cannot be exercised unless
the prior option to extend or renew this Lease has been so exercised.

                                       -5-
<PAGE>
         39.4  Effect of Default on Options.

                  (a) Lessee shall have no right to exercise an Option,
notwithstanding any provision in the grant of Option to the contrary, (i) during
the time commencing from the date Lessor gives to Lessee a notice of default
pursuant to paragraph 13.1(b) or 13.1(c) and continuing until the default
alleged in said notice of default is cured, or (ii) during the period of time
commencing on the day after a monetary obligation to Lessor is due from Lessee
and unpaid (without any necessity for notice thereof to Lessee) continuing until
the obligation is paid, or (iii) at any time after an event of default described
in paragraphs 13.1(a), 13.1(d), or 13.1(e) (without any necessity of Lessor to
give notice of such default to Lessee), or (iv) in the event that Lessor has
given to Lessee three or more notices of default under paragraph 13.1(b), where
a late charge has become payable under paragraph 13.4 for each of such defaults,
or paragraph 13.1(c), whether or not the defaults are cured, during the 12 month
period prior to the time that Lessee intends to exercise the subject Option.

                  (b) The period of time within which an Option may be exercised
shall not be extended or enlarged by reason of Lessee's inability to exercise an
Option because of the provisions of paragraph 39.4(a).

                  (c) All rights of Lessee under the provisions of an Option
shall terminate and be of no further force or effect, notwithstanding Lessee's
due and timely exercise of the Option, if, after, such exercise and during the
term of this Lease, (i) Lessee fails to pay to Lessor a monetary obligation of
Lessee for a period of 30 days after such obligation becomes due (without any
necessity of Lessor to give notice thereof to Lessee), or (ii) Lessee fails to
commence to cure a default specified in paragraph 13.1(c) within 30 days after
the date that Lessor gives notice to Lessee of such default and/or Lessee fails
thereafter to diligently prosecute said cure to completion, or (iii) Lessee
commits a default described in paragraph 13.1(a), 13,1(d) or 13.1 (e) (without
any necessity of Lessor to give notice of such default to Lessee), or (iv)
Lessor gives to Lessee three or more notices of default under paragraph 13.1(b),
where a late charge becomes payable under paragraph 13.4 for each such default,
or paragraph 13.1(c), whether or not the defaults are cured.

40. Multiple Tenant Building. In the event that the Premises are part of a
larger building or group of buildings then Lessee agrees that it will abide by,
keep and observe all reasonable rules and regulations which Lessor may make from
time to time for the management, safety, care, and cleanliness of the building
and grounds, the parking of vehicles and the preservation of good order therein
as well as for the convenience of other occupants and tenants of the building.
The violations of any such rules and regulations shall be deemed a material
breach of this Lease by Lessee.

41. Security Measures. Lessee hereby acknowledges that the rental payable to
Lessor hereunder does not include the cost of guard service or other security
measures, and that Lessor shall have no obligation whatsoever to provide same.
Lessee assumes all responsibility for the protection of Lessee, its agents and
invites from acts of third parties.

42. Easements. Lessor reserves to itself the right, from time to time, to grant
such easements, rights and dedications that Lessor deems necessary or desirable,
and to cause the recordation of Parcel Maps and restrictions, so long as such
easements, rights, dedications, Maps and restrictions do not unreasonably
interfere with the use of the Premises by Lessee. Lessee shall sign any of the
aforementioned documents upon request of Lessor and failure to do so shall
constitute a material breach of this Lease.

43. Performance Under Protest. If at any time a dispute shall arise as to any
amount or sum of money to be paid by one party to the other under the provisions
hereof, the party against whom the obligation to pay the money is asserted shall
have the right to make payment "under protest" and such payment shall not be
regarded as voluntary payment, and there shall survive the right on the part of
said party of institute suit for recovery of each sum. If it shall be adjudged
that there was no legal obligation on part of said party to pay such sum or any
part thereof, said party shall be entitled to recover such sum or so much
thereof as it was not legally required to pay under the provisions of this
Lease.

44. Authority. If Lessee is a corporation, trust, or general or limited
partnership, each individual executing this Lease on behalf of such entity
represents and warrants that he or she is duly authorized to execute and deliver
this Lease on behalf of said entity. If Lessee is a corporation, trust or
partnership, Lessee shall, within thirty (30) days after execution of this
Lease, deliver to Lessor evidence of such authority satisfactory to Lessor.

45. Conflict. Any conflict between the printed provisions of this Lease and the
typewritten or handwritten provisions shall be controlled by the typewritten or
handwritten provisions.

46.  Insuring Party.  The insuring party under this lease shall be the Lessee

47. Addendum. Attached hereto is an addendum or addenda containing paragraphs
47.1 through 47.4 which constitutes a part of this Lease.

LESSOR AND LESSEE HAVE CAREFULLY READ AND REVIEWED THIS LEASE AND EACH TERM AND
PROVISION CONTAINED HEREIN AND, BY EXECUTION OF THIS LEASE, SHOW THEIR INFORMED
AND VOLUNTARY CONSENT THERETO. THE PARTIES HEREBY AGREE THAT, AT THE TIME THIS
LEASE IS EXECUTED, THE TERMS OF THIS LEASE ARE COMMERCIALLY REASONABLE AND
EFFECTUATE THE INTENT AND PURPOSE OF LESSOR AND LESSEE WITH RESPECT TO THE
PREMISES.

IF THIS LEASE HAS BEEN FILLED IN IT HAS BEEN PREPARED FOR SUBMISSION TO YOUR
ATTORNEY FOR HIS APPROVAL. NO REPRESENTATION OR RECOMMENDATION IS MADE BY THE
AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION OR BY THE REAL ESTATE BROKER OR ITS
AGENTS OR EMPLOYEES AS TO THE LEGAL SUFFICIENCY, LEGAL EFFECT, OR TAX
CONSEQUENCES OF THIS LEASE OR THE TRANSACTION RELATING THERETO; THE PARTIES
SHALL RELY SOLELY UPON THE ADVICE OF THEIR OWN LEGAL COUNSEL AS TO THE LEGAL AND
TAX CONSEQUENCES OF THIS LEASE.

The parties hereto have executed this Lease at the place on the dates specified
immediately adjacent to their respective signatures.

BOWMAN MERRITT AND VIRGINIA MERRITT TRUST

By /s/Virginia Merritt
Virginia Merritt, Trustee

By /s/Kim Merritt Campot
Kim Merritt Campot
"LESSOR"

XOMA CORPORATION

By /s/Clarence L. Dellio
Clarence L. Dellio
Senior Vice President, Operations
"LESSEE"
<PAGE>
                                ADDENDUM TO LEASE

         ADDENDUM to lease dated October 12, 1992 between XOMA Corporation,
("XOMA"), Lessee, and Virginia Merritt as Trustee of the Bowman and Virginia
Merritt as Trustee of the Bowman and Virginia Merritt Trust ("Merritt"), Lessor,
for approximately 18,000 sq. ft. at 1545 17th Street, Santa Monica, California
90404.

Paragraph 47.1. The minimum monthly rent provided for in Paragraph 4 shall be
subject to adjustment at the 1994 anniversary of the commencement date of the
lease and every other year thereafter ("the adjustment date") as follows:

         The base for computing the adjustment is the Los Angeles-Long
Beach-Anaheim All Urban Workers, published by United States Department of Labor,
Bureau of Labor Statistics ("Index"), which is in effect on the date of the
commencement of the term ("Beginning Index"). The index published most
immediately preceding the adjustment date in question ("Extension Index") is to
be used in determining the amount of the adjustment. If the Extension Index has
increased over the Beginning Index, the minimum monthly rent for the following
two years (until the next rent adjustment) shall be set by multiplying the
minimum monthly rent set forth in paragraph 4 by a fraction, the numerator of
which is the Extension Index and the denominator of which is the Beginning
Index. In no case shall the minimum monthly rent set forth in paragraph 4 by a
fraction, the numerator of which is the Extension Index and the denominator of
which is the Beginning Index. In no case shall the minimum monthly rent be less
than the monthly rent in effect immediately prior to the adjustment date then
occurring. On adjustment of the minimum monthly rent as provided in this lease,
lessee shall immediately commence to pay the new monthly rent retroactive to the
adjustment date and the parties shall immediately execute an amendment to this
lease stating the new minimum monthly rent.

         If the Index has changed so that the base year differs from that in
effect when the term commences, the Index shall be converted in accordance with
the conversion factor published by the United States Department of Labor, Bureau
of Labor Statistics. If the Index is discontinued or revised during the term,
such other government index or computation with which it is replaced shall be
used in order to obtain substantially the same result as would be obtained if
the Index had not been discontinued or revised.

Paragraph 47.2. Lessee shall receive a credit of $25,144.00 for deposit
previously made on account of the previous lease dated August 1, 1990,
therefore, Lessee need make no additional deposit.

Paragraph 47.3. Lessee to pay premiums for fire and multi-peril insurance
chargeable against the building and the improvements during the term hereof, as
additional rent.

Paragraph 47.4. Within twelve (12) months of the date of this lease, Lessee
shall complete the construction of all Lessee improvements as appropriate, such
improvements currently having an estimated cost of $1 Million. In consideration
for said improvements, Lessee shall

<PAGE>
receive a credit of $36,000.00 against the first six months of rent, which
$36,000.00 shall be applied $6,000.00 per month commencing with the first rental
payment and continuing for the following five months.

                                    XOMA Corporation

                                    By: /s/Clarence L. Dellio
                                    Sr. Vice President, Operations
                                    "Lessee"

                                    Bowman Merritt and Virginia
                                    Merritt Trust

                                    By:/s/Virginia Merritt
                                    Virgina Merritt, Trustee
                                    "Lessor"

                                    /s/Kim Merritt Campot
                                    Kim Merritt Campot



                            FIRST EXTENSION OF LEASE

     THIS EXTENSION OF LEASE is made on April , 1997, between VIRGINIA MERRITT
and KIM MERRITT CAMPOT, as Trustees of the BOWMAN MERRITT AND VIRGINIA MERRITT
1987 TRUST ("Lessor"), whose address is 1119 23rd Street, #7, Santa Monica,
California 90403, and XOMA CORPORATION ("Lessee"), whose address is 2910 Seventh
Street, Berkeley, California 94710, who agree as follows:

     1. Recitals. This Extension of Lease is made with reference to the
following facts and objectives:

     A. Lessor and Lessee entered into a written lease dated October 12, 1992
("the Lease"), in which the Lessor leased to Lessee, and Lessee leased from
Lessor, premises located in the City of Santa Monica, County of Los Angeles,
California, commonly known as 1545 17th Street, Santa Monica, California
("Premises").

     B. The term of the Lease expires on October 12, 1997.

     C. The parties desire to extend the term for an additional period of three
(3) years.

     2. Extension of Term. The term of the Lease shall be extended for an
additional period of three (3) years from and after October 13, 1997 so that the
term of the Lease shall extend to and include October 12, 2000.

     3. Minimum Monthly Rent. Commencing October 13, 1997, the Minimum Monthly
Rent for the extended term shall be $19,200.00 and shall be payable pursuant to
the provisions of the Lease. The next rent adjustment under Article 47.1 of the
Lease shall be on November 1, 1998.

     4. Effectiveness of Lease. Except as set forth in this Extension of Lease,
all the provisions of the Lease shall remain unchanged and in full force and
effect.

LESSOR:                             LESSEE:

BOWMAN MERRITT AND VIRGINIA         XOMA CORPORATION
MERRITT 1987 TRUST

By /s/ Virginia Merritt             By /s/ W. Courtney McGregor 4/23/97

By       /s/ Kim Merritt Campot
         Kim Merritt Campot,
         Trustee





[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission

                                LICENSE AGREEMENT
                                     between
                                XOMA CORPORATION
                                       and
                   THE REGENTS OF THE UNIVERSITY OF CALIFORNIA

U.C. AGREEMENT
CONTROL NUMBER
86-04-0012

<PAGE>
                                TABLE OF CONTENTS

Article No.                Title                                     Page

1                          DEFINITIONS                                  3
2                          GRANT                                        7
3                          SUBLICENSES                                  8
4                          LICENSE ISSUE FEE                            9
5                          ROYALTIES                                    9
6                          DUE DILIGENCE                               16
7                          MOST FAVORED LICENSEE                       19
8                          QUARTERLY REPORTS                           19
9                          BOOKS AND RECORDS                           20
10                         LATE PAYMENTS                               22
11                         LIFE OF THE AGREEMENT                       22
12                         TERMINATION BY THE REGENTS                  23
13                         TERMINATION BY LICENSEE                     23
14                         DISPOSITION OF THE HYBRIDOMA AND
                             LICENSED PRODUCTS ON HAND
                             UPON TERMINATION                          24
15                         MAINTENANCE OF PROPERTY AND
                             TRADE SECRET RIGHTS IN THE
                             HYBRIDOMAS                                25
16                         PATENT PROSECUTION AND MAINTENANCE          25
17                         INFRINGEMENT                                27
18                         NOTIFICATION AND AUTHORIZATION UNDER
                             DRUG PRICE COMPETITION AND PATENT
                             TERM RESTORATION ACT                      30
19                         EXTENSION OF PATENT TERM UNDER DRUG
                             PRICE COMPETITION AND PATENT TERM
                             RESTORATION ACT                           31
20                         PATENT MARKING                              31
21                         USE OF NAME, TRADE NAMES, AND
                             TRADEMARKS                                31
22                         WARRANTY BY THE REGENTS                     32
23                         WAIVER                                      33
24                         LICENSE RESTRICTIONS                        33
25                         ASSIGNABILITY                               34
26                         INDEMNITY                                   34
27                         FOREIGN LICENSE REGISTRATION                34
28                         FORCE MAJEURE                               34
29                         NOTICES                                     35
30                         GOVERNING LAWS                              35
31                         MISCELLANEOUS                               36
<PAGE>
UC Cases:  85-158-1,2; 86-069-1 and 86-073-1 (Young)
082886
                                                                  U.C. AGREEMENT
                                                                  CONTROL NUMBER
                                                                      86-04-0012

          LICENSE AGREEMENT FOR MONOCLONAL ANTIBODIES TO GRAM NEGATIVE
                  SEPSIS-RELATED BACTERIA AND HUMAN DIAGNOSTICS
                       AND THERAPEUTICS DERIVED THEREFROM

     THIS LICENSE AGREEMENT is made and is effective this 3rd day of September
1986 by and between THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California
corporation having statewide administrative offices at 2199 Addison Street,
Berkeley, California 94720, hereinafter referred to as "The Regents", and XOMA
CORPORATION, a Delaware corporation having a principal place of business at 2910
Seventh Street, Berkeley, California 94710, hereinafter referred to as
"Licensee".

                                   WITNESSETH:

     WHEREAS, certain inventions, generally characterized as MONOCLONAL
ANTIBODIES TO GRAM NEGATIVE SEPSIS-RELATED BACTERIA AND DIAGNOSTICS AND
THERAPEUTICS DERIVED THEREFROM, hereinafter collectively referred to as "the
Invention", were made by Lowell Young at the University of California, Los
Angeles and are covered by The Regents' Patent Rights as defined below;

     WHEREAS, Licensee has funded the total direct and indirect costs of
research on the Invention at the University of California, Los Angeles under the
Service to Industry Agreement

<PAGE>

between  Licensee  and  The  Regents  entitled  "Monoclonal  Antibodies  Against
Virulent  Factors  of Gram  Negative  Bacilli"  and dated  October  30,  1981 as
amended;

     WHEREAS, Licensee agrees that part of the consideration for this Agreement
is the expectancy of receiving access to The Hybridomas as defined in paragraph
1.2 for use by Licensee in developing commercial products prior to the issuance
of a patent and, in the event a patent does not issue, prior to access to The
Hybridomas by other commercial entities, if any.

     WHEREAS, the parties have agreed that the royalties established in this
Agreement are appropriate for sales of Diagnostic Kits and Therapeutic Agents,
as defined in paragraphs 1.8 and 1.9, but may not be appropriate for sales of
component parts per se of Diagnostic Kits or Therapeutic Agents; and the parties
have therefore agreed, for their mutual convenience, to calculate all royalties
on the sale of Diagnostic Kits or Therapeutic Agents, whether sold by Licensee
or a third party which purchases component parts from Licensee and then converts
such component parts to Diagnostic Kits or Therapeutic Agents;

         WHEREAS, The Regents desire that the Invention be developed and
utilized to the fullest extent so that the benefits can be enjoyed by the
general public; and

     WHEREAS, Licensee is desirous of obtaining certain rights from The Regents
for the commercial development, use, and sale of the Invention, and The Regents
are willing to grant such rights.

     NOW, THEREFORE, for and in consideration of the covenants, conditions and
undertaking hereinafter set forth, it is agreed by and between the parties, as
follows:

                                       -2-
<PAGE>
                                 1. DEFINITIONS

     1.1 "Regents' Patent Rights", as used herein, means patent rights to any
subject matter claimed in or covered by any of the following:

     1.1(a) Pending U.S. patent application, serial number 781,242, entitled
          "Monoclonal Antibody Reactive with Pseudomonas Aeruginosa", filed on
          September 27, 1985 by Lowell Young and assigned to The Regents; any
          continuing applications thereof including divisions; any
          continuation-in-part applications thereof which include only such
          additional information as can be shown by written records to have been
          known to The Regents prior to the effective date of this Agreement;
          any patents issuing on said application or continuing applications
          including reissues; and any corresponding foreign patents or patent
          applications.

     1.1(b) Pending U.S. patent application, serial number 855,878, entitled
          "Monoclonal Antibodies Binding Determinants of Gram Negative
          Bacteria", filed on April 24, 1986 by Lowell Young and assigned to The
          Regents; any continuing applications thereof including reissues; any
          continuation-in-part applications thereof which include only such
          additional information as can be shown by written records to have been
          known to The

                                       -3-
<PAGE>
          Regents prior to the effective date of this Agreement; and any
          corresponding foreign patents or patent applications.

     1.2 "The Hybridomas", as used herein, means the hybridomas designated as
XMMEN-OE5, XMMEN-LY1, XMMEN-LY2, XMMPS-OP1, XMMPSOP2, XMMPS-OP3, XMMPS-OP4,
XMMPS-OP7, XMMEN-JD5, XMMEN-LY7, and XMMPS-605 described in Regents' Patent
Rights and the hybridomas A4.1 and G7.1 (nomenclature of Dr. Lowell Young's
laboratory) and any progeny or cell line derivatives thereof.

     1.3 "Patent Products", as used herein, means any product, apparatus, kit or
component part thereof, or other subject matter whose manufacture, use, or sale
is covered by any claim or claims included within Regents' Patent Rights, except
that The Hybridomas and all cell line derivatives made from The Hybridomas by
Licensee are expressly excluded under this definition of Patent Products.

     1.4 "Non-Patent Products", as used herein, means any product, apparatus,
kit, or any component part thereof which is not covered by Regents' Patent
Rights and which contains antibodies or fragments of antibodies which are made
by The Hybridomas or cell line derivatives of The Hybridomas made by Licensee.

     1.5 "Licensed Products", as used herein, means both Patent Products and
Non-Patent Products.

     1.6 "Patent Method", as used herein, means any method, procedure, process
or other subject matter whose use or practice is covered by any claim or claims
included within Regents' Patent Rights.

                                       -4-
<PAGE>
     1.7 "...covered by...", as used herein, means Patent Products that when
made, used, or sold or Patent Method which when practiced by Licensee or its
sublicensees would constitute, but for the license granted to Licensee pursuant
to this Agreement, an infringement of any claim or claims of Regents' Patent
Rights.

     1.8 "Diagnostic Kits", as used herein, means Licensed Products which are in
a physical form, irrespective of concentration or packaging, which is ready for
use in a clinical laboratory for diagnostic purposes.

     1.9 "Therapeutic Agents", as used herein, means Licensed Products which are
in a final formulation, irrespective of concentration or packaging, which could
be administered to a patient for therapy.

     1.10 "Affiliate", as used herein, means any corporation which controls, is
controlled by, or is under common control with Licensee. A corporation shall be
regarded as in control of another corporation if it owns or directly or
indirectly controls at least 50% of the voting stock of the other corporation.

     1.11 "Net Sales", as used herein, means the gross invoice price of Licensed
Products sold, less the sum of the following deductions where applicable: cash,
trade or quantity discounts, if any; sales, use, tariff, import/export duties or
other excise taxes imposed upon particular sales; transportation charges; free
samples given for marketing purposes; and allowances or credits to customers
because of rejections or returns. Sales between divisions or departments of
Licensee shall not be considered sales for purposes of this paragraph.

                                       -5-
<PAGE>
     1.12 "Cost of the Hybridoma", as used herein, means the fully allocated
manufacturing or acquisition cost of the supernatant containing antibodies made
from the Hybridoma.

     1.13 "Cost of the Final Product", as used herein, means the fully allocated
manufacturing or acquisition cost of a Diagnostic Kit or Therapeutic Agent.

     1.14 "Antibody Conjugates", as used herein, means antibodies or antibody
fragments which are associated with biologically active molecules such as, but
not limited to, toxins or radiolabels.

     1.15 "the Fraction", as used herein, means (a) for any Therapeutic Agent
containing multiple antibodies or Antibody Conjugates which are sold separately,
the sum of the separate selling prices of all antibodies or Antibody Conjugates
contained in the Therapeutic Agent which are Licensed Products divided by the
sum of the separate selling prices of all antibodies or Antibody Conjugates
contained in the Therapeutic Agent, (b) for any Diagnostic Kit containing
multiple antibodies which are each sold in a separate diagnostic kit containing
only one antibody (Stand Alone Kit), the sum of the separate selling prices of
all Stand Alone Kits which are Licensed Products contained within the Diagnostic
Kit divided by the sum of the separate selling prices of all Stand Alone Kits
contained in the Diagnostic Kit, or (c) for Therapeutic Agents or Diagnostic
Kits which contain parts that are not sold separately, a fraction which shall be
negotiated in good faith by the parties for each such product and which shall
reflect the value of the parts which are Licensed Products relative to the total
value of the product.

                                       -6-
<PAGE>
                                    2. GRANT

     2.1 Except as otherwise provided herein, The Regents hereby grant to
Licensee an exclusive license under Regents' Patent Rights to make (propagate),
have made, make derivatives and use The Hybridoma and all derivatives made
therefrom by Licensee; to make, have made, use and sell Licensed Products,
including, but not limited to, Licensed Products for both diagnostic and
therapeutic purposes; and to practice the Patent Method throughout the world
where The Regents may lawfully grant such a license.

     2.2 Except as otherwise provided herein, The Regents also hereby grant to
Licensee an exclusive license under The Regents' property rights in The
Hybridomas to make (propagate), have made, make derivatives and use The
Hybridomas and all derivatives made therefrom by Licensee and to make, have
made, use and sell Licensed Products, including, but not limited to, Licensed
Products for both diagnostic and therapeutic purposes, throughout the world
where The Regents may lawfully grant such a license.

     2.3 Under The Regents' property and Patent Rights, the right to sell,
donate or otherwise irrevocably transfer The Hybridomas to third parties, except
as provided in paragraph 3.1, is expressly excluded from this license.

     2.4 The Regents expressly reserve the right to use the Invention and
associated technology for educational and research purposes and to transfer The
Hybridoma to third parties for noncommercial uses according to the conditions
described in paragraph 15.1.

                                       -7-
<PAGE>
                                 3. SUBLICENSES

     3.1 The Regents also grant to Licensee the right to issue sublicenses with
respect to the licenses granted in paragraphs 2.1 and 2.2 and the right to
transfer The Hybridomas to potential sublicensees under obligations of
confidentiality at least as restrictive as those used by Licensee to transfer
its own biological materials of similar proprietary nature and value. All
sublicenses shall include all of the rights and obligations due The Regents that
are contained in this Agreement with the exceptions that sublicensees shall not
be obligated to pay the License Issue Fee (paragraph 4.1) or minimum annual
royalties (paragraph 5.7) and Licensee shall be solely responsible, either
directly or through its sublicensees, for the attainment of due diligence
obligations under Article 6.

     3.2 Licensee shall provide The Regents with a copy of each sublicense
issued hereunder which conveys the right to sell Licensed Products
(identification of sublicensee, financial terms and portions not relevant to The
Regents' license to Licensee may be obliterated); collect and guarantee payment
of all royalties due The Regents from sublicensees; and summarize and deliver
all reports due The Regents from sublicensees.

     3.3 Upon termination of this Agreement pursuant to Article 12, Licensee
shall provide The Regents with a complete copy of all sublicenses, and The
Regents agree to negotiate in good faith for a license agreement under Regents'
Patent Rights with any and all of Licensee's sublicensees who have the right to
sell Licensed Products. The resulting license agreements shall

                                       -8-
<PAGE>
contain financial terms no less favorable to the sublicensees than those
previously obtained by them from Licensee.

                              4. LICENSE ISSUE FEE

     4.1 Licensee shall pay to The Regents a License Issue Fee of Seven Thousand
Five Hundred Dollars ($7,500.00) upon execution of this Agreement.

     4.2 This fee is non-refundable and not an advance against earned royalties.

                                  5. ROYALTIES

     5.1 As consideration for this license, Licensee shall pay to The Regents an
earned royalty which shall be calculated by multiplying the royalty rate as set
forth below by the Net Sales of Licensed Products sold by Licensee or its
sublicensees. Such royalties shall accrue and be payable to The Regents,
pursuant to paragraph 5.6, when Licensed Products are sold.

         For Licensed Products containing, among other things, a single
         antibody, the royalty rate shall be calculated according to
         subparagraphs (5.1a) through (5.1d):

     (5.1a) For Therapeutic Agents which are Patent Products and do not contain
          an Antibody Conjugate, the calculated royalty rate shall equal five
          percent (5%) times the Cost of the Hybridoma divided by the Cost of
          the Final Product; provided, however, that the immediately above
          calculated royalty rate shall in no event be less than three percent
          (3%). For Therapeutic Agents which are Patent Products and contain an
          Antibody Conjugate, the calculated royalty rate

                                       -9-
<PAGE>
          shall equal two and one-half percent (2.5%) times the Cost of the
          Hybridoma divided by the Cost of the Final Product; provided, however,
          that the immediately above calculated royalty rate shall in no event
          be less than two and one-quarter percent (2.25%).

     (5.1b) For Therapeutic Agents which are Non-Patent Products and do not
          contain an Antibody Conjugate, the calculated royalty rate shall equal
          three and one-half percent (3.5%) times the Cost of the Hybridoma
          divided by the Cost of the Final Product; provided, however, that the
          immediately above calculated royalty rate shall in no event be less
          than one and one-half percent (1.5%). For Therapeutic Agents which are
          Non-Patent Products and contain an Antibody Conjugate, the calculated
          royalty rate shall equal one and three-quarters percent (1.75%) times
          the Cost of the Hybridoma divided by the Cost of the Final Product;
          provided, however, the immediately-above calculated royalty rate shall
          in no event be less than one and one-quarter percent (1.25%).

     (5.1c) For Diagnostic Kits which are Patent Products, the calculated
          royalty rate shall equal four percent (4%) times the Cost of the
          Hybridoma divided by the Cost of the Final Product; provided, however,
          that the immediately above

                                      -10-
<PAGE>
          calculated royalty rate shall in no event be less than two and
          one-half percent (2.5%).

     (5.1d) For Diagnostic Kits which are Non-Patent Products, the calculated
          royalty rate shall equal three percent (3%) times the Cost of the
          Hybridoma divided by the Cost of the Final Product; provided, however,
          that the immediately above calculated royalty rate shall in no event
          be less than one and one-half percent (1.5%).

          For Licensed Products containing, among other things, multiple
          antibodies, the royalty rate shall be calculated according to
          subparagraphs (5.1e) through (5.1i):

     (5.1e) For Therapeutic Agents which are Patent Products, the calculated
          royalty rate shall equal three and one-half percent (3.5%) times the
          Fraction; provided, however, that the immediately above calculated
          royalty rate shall in no event be less than one percent (1%).

     (5.1f) For Therapeutic Agents which are Non-Patent Products, the calculated
          royalty rate shall equal two percent (2.0%) times the Fraction;
          provided, however, that the immediately above calculated royalty rate
          shall in no event be less than one-half percent (0.5%).

     (5.1g) For Therapeutic Agents which contain antibodies conjugated to other
          biologically active components, the adjusted royalty rate shall equal
          one-half (1/2) of the royalty rate

                                      -11-
<PAGE>
          calculated according to either paragraph 5.1e or 5.1f, as appropriate;
          provided, however, that the adjusted royalty rate shall in no event be
          less than one percent (1.0%) for Patent Products and one-half percent
          (0.5%) for Non-patent Products.

          (5.1h) For Diagnostic Kits which are Patent Products, the calculated
               royalty rate shall equal two and one-half percent (2.5%) times
               the Fraction; provided, however, that the immediately above
               calculated royalty rate shall in no event be less than one
               percent (1.0%).

          (5.1i) For Diagnostic Kits which are Non-Patent Products, the
               calculated royalty rate shall equal one and one-half percent
               (1.5%) times the Fraction; provided, however, that the
               immediately above calculated royalty rate shall in no event be
               less than one-half percent (0.5%).

Earned royalties under this paragraph shall be payable in full without deduction
for taxes or levies against such royalty payments by any foreign government
other than taxes levied on the sale of Licensed Products as specified in
paragraph 1.11.

     5.2 If Licensee or Licensee's sublicensees sell Licensed Products which are
not Diagnostic Kits or Therapeutic Agents to a third party, the royalties due
The Regents for such sale shall be calculated from the Net Sales by the third
party of Diagnostic Kits or Therapeutic Agents made from the Licensed Products
sold

                                      -12-
<PAGE>
by Licensee or Licensee's sublicensees. Net Sales of Licensed Products sold or
transferred to Affiliates shall be the gross invoice price of sales by the
Affiliate to third parties which are not Affiliates less the sum of the
deductions listed in paragraph 1.11, where applicable.

     5.3 If the Net Sales by Licensee and Licensee's sublicensees for any
Licensed Product decrease by more than ten percent (10%) over a period of at
least six months and if a competitor offers for sale in the same geographical
market area a product which diagnoses the same disease or treats the same
indication as the Licensed Product throughout the period during which the
decrease in sales occurred, then The Regents and Licensee shall enter into good
faith negotiations to lower the royalty rate on the Licensed Product. The
negotiated royalty rate will be one which places the Licensee in a position to
competitively market the Licensed Product.

     5.4 Earned royalties for Patent Products under paragraphs 5.1, 5.2 and 5.3
shall accrue in each country for the duration of Regents' Patent Rights in that
country. After the expiration of all patents within Regents' Patent Rights which
cover a Licensed Product in a country, Licensee shall have an irrevocable
paid-up license in the country under the rights granted in paragraph 2.2
pertaining to the Licensed Product.

     5.5 Earned royalties for Non-Patent Products under paragraphs 5.1, 5.2 and
5.3 shall accrue in any country for a period of ten (10) years from the date of
first commercial sale in the U.S. of the Non-Patent Product or, if no sale
occurs in the U.S., for a period of ten (10) years from the date of first

                                      -13-
<PAGE>
commercial sale of the Non-Patent Product in the country. After said ten-year
period, Licensee shall have an irrevocable paid-up license in the country to the
rights granted in paragraph 2.2 pertaining to the Non-patent Product.

     5.6 Royalties owing on Licensed Products covered by pending patent
applications but not covered by any issued patents within Regents' Patent Rights
shall be assessed at the rate for Nonpatent Products. In the event Regents'
patent applications listed in paragraph 1.1 are denied, royalties owing on
Licensed Products shall be assessed at the rate for Non-patent Products.

     5.7 Licensed Products shall be considered sold when invoiced or, if not
invoiced, when delivered to a third party by Licensee or its sublicensees.

     5.8 Royalties accruing to The Regents shall be paid to The Regents within
sixty (60) days following the calendar quarter during which they have accrued.

     5.9 Licensee shall pay to The Regents a minimum annual royalty of Fifteen
Thousand Dollars ($15,000.00), beginning with either the first full calendar
year after the approval by the FDA of the first Licensed Product or 1993,
whichever is earlier, and continuing in the amount of Twenty-five Thousand
Dollars ($25,000.00) for all subsequent years throughout the life of Regents'
Patent Rights for as long as Licensee has exclusive rights hereunder in the
United States. This minimum annual royalty shall accrue on and be paid to The
Regents by February 28 of each year and shall be credited against earned
royalties for so long as is necessary to amortize the minimum annual royalties
paid.

                                      -14-
<PAGE>
     5.10 Except as otherwise provided in this paragraph 5.10, all monies due
The Regents shall be payable in United States funds collectible at par in San
Francisco, California. If at any time legal restrictions prevent the prompt
remittance of part or all royalties by Licensee or any sublicensee with respect
to any country where a Licensed Product is sold, Licensee or such sublicensee
shall have the right and option to make such payments by depositing the amount
thereof in local currency to The Regents' account in a bank or other depository
in such country.

     5.11 In the event that any patent or any claim thereof included within the
Regents' Patent Rights shall be held invalid in a decision by a court of
competent jurisdiction and last resort from which no appeal has or can be taken,
all obligations to pay royalties based on such patent or claim or any claim
patentably indistinct therefrom shall cease as of the date of such decision.
Licensee shall not, however, be relieved from paying any royalties that accrued
before such decision or that are based on another patent or claim not involved
in such decision or that are based on The Regents' property rights. Royalties
for a Licensed Product which becomes a Non-Patent Product due to patent
invalidation shall accrue for a period of ten (10) years from the date of first
commercial sale of the given Licensed Product, regardless of whether the
Licensed Product was a Patent Product or a Non-patent Product at the time of
first commercial sale.

     5.12 A single royalty shall be paid on sales of Licensed Products, no
matter how many items in Regents' Patent Rights or The Regents' property rights
cover such Licensed Products, and

                                      -15-
<PAGE>
the royalty shall be assessed at the highest applicable rate for the Licensed
Product.

     5.13 No royalty shall be paid on a Patent Product or a Patent Method after
Regents' Patent Rights covering said Licensed Product or Method have expired.

                                6. DUE DILIGENCE

     6.1 Licensee, upon execution of this Agreement, shall diligently proceed
with the development, manufacture and sale of Licensed Products and shall
earnestly and diligently endeavor to market the same within a reasonable time
after execution of this Agreement in quantities sufficient to meet the market
demands therefor.

     6.2 Licensee shall be entitled to exercise prudent and justifiable business
judgment in meeting its due diligence obligations hereunder.

     6.3 Licensee shall endeavor to obtain all necessary approvals for the
manufacture, use and sale of Licensed Products.

     6.4 Subject to the provisions of paragraph 6.2, Licensee agrees to use its
best efforts:

        (6.4a)  to file a Product License Application (PLA) for a therapeutic
                Licensed Product with the U. S. Food and Drug Administration
                (FDA) by January 1, 1990;

        (6.4b)  to market such therapeutic Licensed Product in the United States
                within six (6) months after receiving approval from FDA of such
                Licensed Product's PLA;

                                      -16-
<PAGE>
        (6.4c)  to file a Premarket Approval Application (PMA) for a diagnostic
                Licensed Product with the FDA by January 1, 1991;

        (6.4d)  to market such diagnostic Licensed Product in the United States
                within six (6) months after receiving approval from FDA of such
                Licensed Product's PMA;

        (6.4e)  following commencement of marketing, to reasonably fill the
                market demands for Licensed Products in the United States during
                the exclusive period of this Agreement.

If Licensee shall fail to fulfill its obligations relative to therapeutic
Licensed Products under subparagraphs (a), (b) and (e) above, then The Regents
shall have the right and option to reduce Licensee's exclusive license for
therapeutic Licensed Products to a nonexclusive license. If Licensee shall fail
to fulfill its obligations relative to diagnostic Licensed Products under
subparagraphs (c), (d) and (e) above, then The Regents shall have the right and
option to reduce Licensee's exclusive license for diagnostic Licensed Products
to a nonexclusive license. These rights, if exercised by The Regents, supersede
the rights granted in Article 2 (GRANT).

     6.5 The Regents shall have the right to terminate Licensee's exclusive
license in any country or countries in which Licensee or Licensee's sublicensees
demonstrate a grievous failure to market Licensed Products.

     6.6 Licensee shall keep The Regents informed as to the progress in the
development and testing of all Licensed Products

                                      -17-
<PAGE>
and the preparing, filing, and obtaining of the approvals necessary for
marketing. Beginning January 1, 1987 and annually thereafter, Licensee shall
submit to The Regents a progress report covering Licensee's activities related
to the development of Licensed Products and the securing of the requisite
approvals. These reports shall be made until the first commercial sale of a
Licensed Product in the U.S.

     6.7 At the request of either party, any controversy or claim arising out of
or relating to the diligence provisions of this Agreement shall be settled by
arbitration conducted in San Francisco, California in accordance with the then
current Licensing Agreement Arbitration Rules of the American Arbitration
Association. Judgment upon the award rendered by the Arbitrator(s) shall be
binding on the parties and may be entered by either party in the court or forum,
state or federal, having jurisdiction.

     6.8 To exercise the right to either terminate this license or convert this
license to a nonexclusive license for lack of diligence, providing that
arbitration has not been requested, The Regents must give Licensee written
notice of the deficiency. Licensee thereafter has one hundred eighty (180) days
to cure the deficiency or to request arbitration. If The Regents have not
received a written request for arbitration or satisfactory tangible evidence
that the deficiency has been cured by the end of the one hundred eighty-day
period, then The Regents may, at their option, convert Licensee's exclusive
license to a nonexclusive license by giving written notice to Licensee.

                                      -18-
<PAGE>
                            7. MOST FAVORED LICENSEE

     7.1 Any provision of this Agreement to the contrary notwithstanding, if
when otherwise permitted by the terms of this Agreement, The Regents grant to a
third party a license under Regents' Patent Rights which contains royalty terms
more favorable than the terms of this Agreement, then The Regents shall notify
Licensee in writing of all royalty terms in such third party license. Licensee
shall have the right and option to substitute all such royalty terms for all the
respective terms of this Agreement. Such option shall be effective for a period
of sixty (60) days from the date of notice by The Regents of the terms of the
third party license and may be exercised by written notice to The Regents.

                              8. QUARTERLY REPORTS

     8.1 Commencing with the calendar quarter in which the first commercial sale
of Licensed Products takes place, Licensee will make quarterly reports to The
Regents on or before each February 28, May 31, August 31 and November 30 of each
year. Each such report will cover Licensee's most recently completed calendar
quarter and will show (a) the gross sales and the Net Sales of Licensed Products
sold by Licensee and its sublicensees during the most recently completed
calendar quarter; (b) the applicable royalty rate and the method by which it was
calculated pursuant to paragraphs 5.1, 5.2 and 5.3, including the calculation of
the Fraction; (c) the royalties, payable in U.S. dollars, which shall have
accrued hereunder with respect to such sales; (d) the exchange rates used in
determining the amount of

                                      -19-
<PAGE>
U.S. dollars. If no sales of Licensed Products have been made during any
reporting period, a statement to this effect shall be required.

     8.2 With respect to sales of Licensed Products invoiced in U.S. dollars,
the gross sales, Net Sales, and royalty payable shall be expressed in U.S.
dollars. With respect to sales of Licensed Products invoiced in currency other
than U.S. dollars, the gross sales, Net Sales, and royalty payable shall be
expressed in the domestic currency of the party making the sale together with
the U.S. dollar equivalent of the royalty payable, calculated using the
appropriate selling rate for such currency quoted in the Continental terms
method of quoting exchange rates (local currency per U.S. $1) in New York, New
York, on the last day of the reporting period.

     8.3 Pursuant to paragraphs 6.4 and 8.1 herein, Licensee also agrees to
report to The Regents the date of first commercial sale in each country of a
Licensed Product within thirty (30) days of its occurrence in each country.

                              9. BOOKS AND RECORDS

     9.1 Licensee shall maintain books and records accurately showing all
Licensed Products manufactured or sold by it under the terms of this Agreement
for at least three (3) years from the end of the calendar year to which the
books and records pertain. Upon written request and after reasonable notice, not
more often than once in each year, Licensee shall permit a representative
selected by The Regents, except one to whom Licensee has some reasonable
objection, to have access during normal business hours to such records of
Licensee as may be reasonably necessary to

                                      -20-
<PAGE>
determine, with respect to any calendar year ending not more than thirty-six
(36) months prior to the date of such request, the correctness of any report
and/or payment made under this Agreement. Licensee shall include in each
sublicense granted pursuant to this Agreement a provision requiring the
sublicensee to maintain records of sales made pursuant to such sublicense and to
grant access to such records to The Regents' representative. Upon the expiration
of thirty-six (36) months following the end of any calendar year and absent a
showing of fraud, the calculation of royalties payable with respect to such year
shall be binding and conclusive upon The Regents, and Licensee and its
sublicensees shall be released from any liability or accountability with respect
to royalties for such year.

     9.2 Subject to applicable Federal and State laws, the Regents agree that
all information subject to review under paragraph 9.1 is confidential and that
The Regents shall and shall cause their representative to retain all such
information in confidence. In any event, The Regents agree to notify Licensee
prior to the release of any such information pursuant to Federal or State laws,
so as to permit Licensee to take such action as it deems appropriate.

     9.3 The fees and expenses of the representatives performing such an
examination shall be borne by The Regents. However, if an error in royalties in
favor of The Regents by more than ten percent (10%) of the total royalties or
one thousand dollars ($1,000.00), whichever is greater, due hereunder for the
calendar year being reviewed is discovered by the representatives of The

                                      -21-
<PAGE>
Regents, then all reasonable fees and expenses of these representatives shall be
borne by Licensee.

                                10. LATE PAYMENTS

     10.1 In the event royalty payments or fees are not received by The Regents
when due, Licensee shall pay to The Regents interest charges at the rate of ten
percent (10%) per annum on the total royalties or fees due for the reporting
period.

     10.2 In the event of a failure of performance due under the terms of this
Agreement and if it becomes necessary for either party to undertake legal action
against the other on account thereof, then the prevailing party shall be
entitled to reasonable attorney's fees in addition to costs and necessary
disbursements.

                            11. LIFE OF THE AGREEMENT

     11.1 Subject to the provisions of paragraph 11.2, this Agreement shall be
in full force and effect from the date first herein written and shall remain in
effect for the life of the last to expire patent licensed under this Agreement
or for the period of Licensee's royalty obligation as set forth in paragraph
5.4, whichever is longer, or unless otherwise terminated by operation of law or
by acts of the parties in accordance with the terms of this Agreement.

     11.2 Upon termination of this Agreement pursuant to Article 11, Article 12
or Article 13, the rights and obligations of the parties shall cease, except
that (a) rights (including Licensee's right to the paid-up irrevocable licenses
granted in paragraphs 5.4 and 5.5), obligations and liabilities of the parties
accrued prior to such termination shall survive such termination; and (b)

                                      -22-
<PAGE>
the obligation of The Regents, under paragraph 9.2, to keep certain information
confidential, shall survive termination for period of five (5) years.

                         12. TERMINATION BY THE REGENTS

     12.1 It is expressly agreed that, notwithstanding the provisions of Article
10 concerning late payments, if Licensee should fail to deliver to The Regents
any statement or report when due, or fail to pay any royalty at the time that
the same should be due or if Licensee should violate or fail to perform any
covenant, condition, or undertaking of this Agreement on its part to be
performed hereunder, then and in such event The Regents may give written notice
of such default to Licensee. If Licensee should fail to repair such default
within ninety (90) days from such notice, The Regents shall have the right to
terminate this Agreement and the licenses herein by written notice to Licensee.
Upon delivery of such notice of termination to Licensee, this Agreement shall
automatically terminate. Such termination shall not relieve Licensee of its
obligation to pay any royalty or license fees due or owing at the time of such
termination and shall not impair any accrued right of The Regents.

                           13. TERMINATION BY LICENSEE

     13.1 Licensee shall have the right to terminate this Agreement or any
license granted herein, in whole or as to any specified patent or any claim of
such patent, at any time, and from time to time, by giving notice in writing to
The Regents. Such termination shall be effective ninety (90) days from the

                                      -23-
<PAGE>
date of such notice and all Licensee's rights associated therewith shall cease
as of that date.

     13.2 Any termination pursuant to the above paragraph shall not relieve
Licensee of any obligation or liability accrued hereunder prior to such
termination, or rescind or give rise to any right to rescind anything done by
Licensee or any payments made (including the payment of the license issue fee)
or other consideration given to The Regents hereunder prior to the time such
termination becomes effective, and such termination shall not affect in any
manner any rights of The Regents arising under this Agreement prior to such
termination.

                      14. DISPOSITION OF THE HYBRIDOMA AND
                   LICENSED PRODUCTS ON HAND UPON TERMINATION

     14.1 Upon termination of this Agreement by either party Licensee agrees to
dispose of The Hybridomas and Licensed Products in its possession in the
following manner:

        (14.1a) The Hybridomas will be destroyed within fifteen (15) days
                following the effective date of termination. Licensee agrees to
                provide The Regents within thirty (30) days following said
                termination date with written notice that The Hybridoma has been
                destroyed.

        (14.1b) In the case of Licensed Products, Licensee shall provide The
                Regents within sixty (60) days following the effective date of
                termination with a written inventory of all Licensed Products in
                process of manufacture, in use or in stock, and shall dispose of
                such

                                      -24-
<PAGE>
                Licensed Products within one hundred eighty (180) days of the
                effective date of termination, provided, however, that all such
                Licensed Products shall be subject to the terms of this
                Agreement.

               15. MAINTENANCE OF PROPERTY AND TRADE SECRET RIGHTS
                                IN THE HYBRIDOMAS

     15.1 The Regents agree to instruct Lowell Young to circulate The Hybridomas
to third parties only for noncommercial research purposes and only under the
terms of the biological material transmission letter attached hereto as Appendix
A.

     15.2 Licensee shall not be prevented from transferring any of The
Hybridomas to third parties if:

        (l5.2a) such Hybridoma is now, or becomes in the future, publicly
                available, other than through acts or omissions of Licensee; or

        (15.2b) such Hybridoma is lawfully obtained by Licensee from sources
                independent of The Regents.

     15.3 Licensee agrees to use its best efforts to preserve The Regents"
tangible property and trade secret rights in The Hybridomas.

                     16. PATENT PROSECUTION AND MAINTENANCE

     16.1 The Regents shall diligently prosecute and maintain the above
identified United States patent application using counsel of their choice and
after due consultation with Licensee. The Regents shall provide Licensee with
copies of all relevant documentation so that Licensee may be informed and
apprised of

                                      -25-
<PAGE>
the continuing prosecution, and Licensee agrees to keep this
documentation confidential.

     16.2 The Regents shall use their best efforts to amend any patent
application to include claims reasonably requested by Licensee and required to
protect the Licensed Products contemplated to be sold under this Agreement.

     16.3 The cost of preparing, filing and prosecuting all United States patent
applications contemplated by this Agreement shall be borne by Licensee.

     16.4 Licensee shall have the right to obtain patent protection on the
Invention in foreign countries if available and if it so desires. Licensee must
notify The Regents within ten (10) months of the filing of the corresponding
United States application of those countries in which it desires to obtain
foreign patents. The absence of a decision in writing from Licensee to The
Regents shall be considered an election by Licensee not to secure foreign patent
rights.

     16.5 The preparation, filing and prosecuting of all foreign patent
applications filed in accordance with paragraph 16.4 and the maintenance of all
resulting patents shall be at the sole expense of Licensee. Such patents shall
be held in the name of The Regents and shall be obtained using counsel of The
Regents' choice, provided that Licensee shall have no reasonable objection to
such counsel.

     16.6 Licensee's obligation to underwrite and to pay foreign patent
prosecution costs filed at its request shall continue for so long as this
Agreement remains in effect, provided, however, that Licensee may terminate its
obligations with respect to any

                                      -26-
<PAGE>
foreign patent application or patent upon three (3) months' written notice to
The Regents. The Regents may continue prosecution and/or maintenance of such
application(s) or patent(s) at their sole discretion and expense; provided,
however, that Licensee shall have no further right or licenses thereunder.

     16.7 The Regents shall have the right to file patent applications at their
own expense in any country in which Licensee has not elected to secure such
rights, and such applications and resultant patents shall not be subject to this
Agreement.

                                17. INFRINGEMENT

     17.1 In the event that Licensee shall learn of the infringement of any
patent licensed under this Agreement, Licensee shall call The Regents' attention
thereto in writing. Both Parties to this Agreement agree that during the period
and in a jurisdiction where Licensee has exclusive rights under this Agreement,
neither will notify a third party of the infringement of any of Regents' Patent
Rights without first obtaining the consent of the other Party, which consent
shall not be unreasonably denied. Both Parties shall use reasonable efforts in
cooperation with each other to terminate such infringement without litigation.

     17.2 Licensee may request that The Regents take legal action against the
infringement of Regents' Patent Rights. Such request shall be made in writing
and shall include reasonable evidence of such infringement and damages to
Licensee. If the infringing activity has not been abated within ninety (90) days

                                      -27-
<PAGE>
following the effective date of such request, The Regents shall have the right
to:

        (17.2a) commence suit on their own account; or

        (17.2b) refuse to participate in such suit,

and The Regents shall give notice of their election in writing to Licensee by
the end of the one-hundredth (100th) day after receiving notice of such request
from Licensee. Licensee may thereafter bring suit for patent infringement if and
only if The Regents elect not to commence suit (other than as nominal party
plaintiff) and if the infringement occurred during the period and in a
jurisdiction where Licensee had exclusive rights under this Agreement. However,
in the event Licensee elects to bring suit in accordance with this paragraph,
The Regents may thereafter join such suit at their own expense.

     17.3 In the case of an infringement of Regents' Patent Rights as defined in
Section 271(e) of Title 35 of the United States Code, Licensee shall provide The
Regents with written notice of such occurrence and shall provide The Regents
with copies of any notice which Licensee receives as required by the Drug Price
Competition and Patent Term Restoration Act (Public Law 98-417, hereinafter "the
Act") to be given by an applicant for an abbreviated PLA or a "paper PLA"
pursuant to section 101 or 103 of the Act to a holder of an approved PLA. If
Licensee wishes action to be taken against such infringement, as provided in the
Act, Licensee shall request such action in written notice to The Regents. Within
thirty (30) days of receiving said request, The Regents will give written notice
to Licensee of its election to:

                                      -28-
<PAGE>
        (17.3a) commence suit on their own account; or

        (17.3b) refuse to participate in such suit.

Licensee may thereafter bring suit for patent infringement as provided by the
Act if and only if The Regents elect not to commence suit (other than as nominal
party plaintiff) and if the infringement occurred during the period that
Licensee had exclusive rights in the United States under this Agreement.
However, in the event Licensee elects to bring suit in accordance with this
paragraph, The Regents may thereafter join such suit at their own expense.

     17.4 Any legal action as is brought shall be at the expense of the party by
whom suit is filed. Any damages or costs recovered in connection with a lawsuit
shall belong to the party by whom suit is filed. Nothing herein obligates The
Regents or Licensee to enter into any litigation of any nature whatsoever with
regard to Regents' Patent Rights.

     17.5 Each party agrees to cooperate with the other in litigation
proceedings instituted hereunder but at the expense of the party on account of
whom suit is brought. Such litigation shall be controlled by the party bringing
the suit, except when such suit is brought jointly in which case The Regents
shall control. The Regents, at their own expense, may be represented by counsel
of their choice pursuant to The Regents' determination in any suit brought by
Licensee.

     17.6 In the event that The Regents refuse to participate in a suit and
Licensee brings same as allowed herein, Licensee may pay royalties at the
applicable rate for Non-patent Products and may withhold the difference between
the rate paid and the rate

                                      -29-
<PAGE>
due for Patent Products during the pendency of the suit and until said suit has
been finally concluded. To the extent that Licensee does not recover attorneys'
fees and other out-of-pocket costs as a result of such litigation, such withheld
royalties may be applied to Licensee's expenses (out-of-pocket and in-house)
incurred in connection with such suit and the balance of such withheld royalties
if any, shall be paid to The Regents upon disposition of the suit; provided
however, that if as a result of such suit, all claims of patents included within
Regents' Patent Rights under which Licensee is selling a Licensed Product shall
be held invalid, Licensee may retain the balance of such withheld royalties
which pertain to such Licensed Product until such decision shall be finally
reversed by an unappealed or unappealable decree of a court of competent
jurisdiction and higher dignity.

               18. NOTIFICATION AND AUTHORIZATION UNDER DRUG PRICE
                   COMPETITION AND PATENT TERM RESTORATION ACT

     18.1 The Regents shall notify Licensee of (a) the issuance of each U.S.
patent included within Regents' Patent Rights, giving the date of issue and
patent number for each such patent, and (b) each notice pertaining to any patent
included within Regents' Patent Rights which it receives as patent owner
pursuant to the Drug Price Competition and Patent Term Restoration Act, (the
Act), including but not necessarily limited to notices pursuant to Sections 101
and 103 of the Act from persons who have filed an Abbreviated New Drug
Application ("ANDA") or a "paper" New Drug Application (NDA). Such notices shall
be given promptly, but in any event within ten (10) calendar days of each

                                      -30-
<PAGE>
such patent's date of issue or receipt of each such notice pursuant to the Act,
whichever is applicable.

     18.2 The Regents hereby authorize Licensee (a) to include in any NDA for a
Licensed Product, as Licensee may deem appropriate under the Act, a list of
patents included within Regents' Patent Rights identifying The Regents as patent
owner that relate to such Licensed Product and such other information as
Licensee in its reasonable discretion believes is appropriate to be filed
pursuant to the Act; and (b) in consultation with The Regents, to exercise any
rights that may be exercisable by an exclusive licensee and NDA holder under The
Regents' Patent Rights.

                  19. EXTENSION OF PATENT TERM UNDER DRUG PRICE
                   COMPETITION AND PATENT TERM RESTORATION ACT

     19.1 The Regents agree as patent owners under the Act to apply for an
extension of the term of any patent included within Regents' Patent Rights, as
permitted by the Act, upon request by Licensee. The Regents agree to cooperate
with Licensee in the exercise of the authorizations granted in Articles 18 and
19 and will execute such documents and take such additional action as Licensee
may reasonably request in connection therewith.

                               20. PATENT MARKING

     20.1 Licensee agrees to mark all Patent Products made, used or sold under
the terms of this Agreement, or their containers, in accordance with the
applicable patent marking laws.

                  21. USE OF NAMES, TRADE NAMES, AND TRADEMARKS

     21.1 Nothing contained in this Agreement shall be construed as conferring
any right to use in advertising, publicity, or

                                      -31-
<PAGE>
other promotional activities any name, trade name, trademark, or other
designation of either party hereto (including any contraction, abbreviation or
simulation of any of the foregoing). The use of the name "The Regents of the
University of California" or the name of any campus of the University of
California is expressly prohibited.

     21.2 Each party hereto further agrees not to use or refer to this Agreement
or any license granted hereunder in any promotional activity associated with any
Licensed Product licensed hereunder without the express written approval of the
other party.

                           22. WARRANTY BY THE REGENTS

     22.1 The Regents warrant that they have the lawful right to grant this
license.

     22.2 The Regents make no express or implied warranties of merchantability
or fitness of the Invention for a particular purpose.

     22.3 Nothing in this Agreement shall be construed as:

        (22.3a) a warranty or representation by The Regents as to the validity
                or scope of any Regents' Patent Rights; or

        (22.3b) a warranty or representation that anything made, used, sold or
                otherwise disposed of under any license granted in this
                Agreement is or will be free from infringement of patents of
                third parties; or

        (22.3c) an obligation to bring or prosecute actions or suits against
                third parties for patent

                                      -32-
<PAGE>
                infringement except as provided in Article 17; or

        (22.3d) conferring by implication, estoppel or otherwise any license or
                rights under any patents of The Regents other than Regents'
                Patent Rights as defined herein, regardless of whether such
                patents are dominant or subordinate to Regents' Patent Rights;
                or

        (22.3e) a warranty or representation by The Regents that The Hybridomas
                will not be publicly disclosed and that any trade secret covered
                by this Agreement will be maintained as such by The Regents,
                notwithstanding the provisions of paragraph 15.1 herein.

     22.4 No liability, financial or otherwise, shall be incurred by The Regents
as a consequence of any disclosure of The Hybridomas to third parties.

                                   23. WAIVER

     23.1 It is agreed that no waiver by either party hereto of any breach or
default of any of the covenants or agreements herein set forth shall be deemed a
waiver as to any subsequent and/or similar breach or default.

                            24. LICENSE RESTRICTIONS

     24.1 It is agreed that the rights and privileges granted to Licensee are
each and all expressly conditioned upon the faithful performance on the part of
Licensee of every requirement herein contained. Each of such conditions and
requirements is a specific license restriction.

                                      -33-
<PAGE>
                                25. ASSIGNABILITY

     25.1 This Agreement is binding upon and shall inure to the benefit of The
Regents, their successors and assigns, but shall be personal to Licensee and
assignable by Licensee only with the written consent of The Regents, which
consent shall not be unreasonably withheld.

                                  26. INDEMNITY

     26.1 Licensee agrees to indemnify, hold harmless and defend The Regents,
their officers, employees, and agents, against any and all claims, suits,
losses, damages, costs, fees, and expenses resulting from or arising out of
exercise of the licenses granted in this Agreement.

                        27. FOREIGN LICENSE REGISTRATION

     27.1 Licensee agrees to register or give required notice concerning this
Agreement, through itself or through an Affiliate, in each country where there
exists an obligation under law to so register or give notice, to pay all costs
and legal fees connected therewith, and shall otherwise comply with all national
laws applicable to this Agreement.

                                28. FORCE MAJEURE

     28.1 In the event of acts of God, action of the elements, war, invasion,
civil commotion, insurrection, labor disturbance, fire, flood, or government
restriction, which render performance under this Agreement impossible, failure
on that account during each period shall be excused; and any minimum royalty
called for shall not be required during such period or periods of inability to
perform.

                                      -34-
<PAGE>
                                   29. NOTICES

     29.1 Any payment, notice or other communication required or permitted to be
given to either party hereto shall be deemed to have been properly given and to
be effective (a) upon delivery if delivered in person, or (b) four (4) days
after mailing if mailed by first-class certified mail, postage paid, to the
respective address given below, or to such other address as shall be designated
by written notice given to the other party as follows:

In the case of Licensee:            XOMA CORPORATION
                                    2910 Seventh Street
                                    Berkeley, California 94710
                                    Attention: Chief Executive Officer

In the case of The Regents:         THE REGENTS OF THE UNIVERSITY
                                     OF CALIFORNIA
                                    2199 Addison Street
                                    Berkeley, California 94720
                                    Attention: Director, Patent,
                                     Trademark & Copyright Office

All payments, notices or other communications required or permitted to be given
to The Regents will contain the following information:

         UC Case Nos.: 85-158-1,2; 86-069-1 and 86-073-1
         Inventor: Lowell Young

                               30. GOVERNING LAWS

     30.1 This Agreement shall be interpreted and construed in accordance with
the laws of the State of California.

                                      -35-
<PAGE>
                                31. MISCELLANEOUS

     31.1 The headings of the several sections are inserted for convenience of
reference only and are not intended to be a part of or to affect the meaning or
interpretation of this Agreement.

     31.2 This Agreement will not be binding upon the parties until it has been
signed hereinbelow by or on behalf of each party, in which event, it shall be
effective as of the date first above written.

     31.3 No amendment or modification hereof shall be valid or binding upon the
parties unless made in writing and signed as aforesaid.

     31.4 This Agreement embodies the entire understanding of the parties and
shall supersede all previous communications, representations or understandings,
either oral or written, between the parties relating to the subject matter
hereof.

     31.5 In case any one or more of the provisions contained in this Agreement
shall for any reason be held to be invalid, illegal or unenforceable in any
respect, such invalidity, illegality or unenforceability shall not affect any
other provisions hereof, but this Agreement shall be construed as if such
invalid or illegal or unenforceable provisions had never been contained herein.

     31.6 Nothing contained herein shall prohibit The Regents or their officers,
agents, employees, or students from publishing results of any research based on
or using The Hybridomas or any other commentary related to The Hybridomas.

                                      -36-
<PAGE>
     IN WITNESS WHEREOF, both The Regents and Licensee have executed this
Agreement, in duplicate originals, by their respective officers hereunto duly
authorized, on the day and year hereinafter written.

XOMA CORPORATION                            THE REGENTS OF THE UNIVERSITY
                                              OF CALIFORNIA

By  /s/Steven C. Mendell                    By  /s/Roger G. Ditzel

By  Steven C. Mendell                       By  ROGER G. DITZEL
    (Please Print)                                (Please Print)

Title  Chairman and                         Title  Director, Patent,
       Chief Executive Officer              Trademark & Copyright Ofc

Date  September 3, 1986                     Date  17 SEPT 86

"License Agreement between Xoma Corporation and The Regents of the University of
California. UC Case Nos.: 85-158-1,2; 86-069-1 and 86-073-1"

                                      -37-
<PAGE>
                                                                    "Appendix A"

                            UNIVERSITY OF CALIFORNIA

                        Instructions for Standard Letter
                        Transmitting Biological Materials
                   to Universities and Nonprofit Institutions

     The attached letter is authorized for use by University of California
Principal Investigators and Administrators only with scientists at other
universities and nonprofit research institutions when transmitting cell lines,
plasmids and the like for non-commercial research purposes.

1. Choose the appropriate form of university or nonprofit research institution
in paragraph 2.

2. Choose whether or not to include the phrase "our cooperative" in paragraph 2.

3. Insert in paragraph 4 the amount of processing charge. If the material is to
be shipped at no charge, insert the words "no charge."

4. Send the letter in duplicate to the other scientist.

5. Do not send biological materials until you receive the duplicate copy
executed by both the scientist and the other institution.

6. Send a copy of the fully executed letter agreement to:

                            Roger G. Ditzel, Director
                     Patent, Trademark and Copyright Office
                            University of California
                         2490 Channing Way, Third Floor
                           Berkeley, California 94720

7. Any changes in the wording of this standard letter must be reviewed by the
director of the Patent, trademark and copyright Office before acceptance.

NOTE: Do not use this letter for the exchange of living plants. A separate
"Testing Agreement for Plant Varieties" is available for that purpose.

December 29, 1981

<PAGE>
                         SAMPLE LETTER FOR USE PRIOR TO
                      TRANSMISSION OF BIOLOGICAL MATERIALS
                            TO INVESTIGATORS AT OTHER
                UNIVERSITIES OR NON PROFIT RESEARCH INSTITUTIONS

                               (Use UC Letterhead)

                                                                          (Date)

                                                                    IN DUPLICATE

To:

This is to [acknowledge receipt of your letter] [confirm our telephone
conversations] in which you requested certain research materials developed in
this laboratory be sent to you for scientific research purposes. The materials
concerned, which belong to The Regents of the University of California, are:
(blank)

I will be pleased to permit your use of these materials within your
[university][non profit research institution]laboratory for [our cooperative]
scientific research. However, before forwarding them to you, I would like your
agreement that the materials will be received by you only for use in [our
cooperative work][scientific research], that you will bear all risk to you or
any others resulting from your use, and that you will not pass these materials,
their progeny or derivatives, on to any other party or use them for commercial
purposes without the express written consent of The Regents of the University of
California. You understand that no other right or license to these materials,
their progeny or derivatives, is granted or implied as a result of our
transmission of these materials to you.

These materials are to be used with caution and prudence in any experimental
work, since all of their characteristics are not known.

As you recognize, there is a processing cost to us involved in providing these
materials to you. We will bill you for our processing costs, which will amount
to $(blank).

<PAGE>
Date
Page Two

If you agree to accept these materials under the above conditions, please sign
the enclosed duplicate copy of this letter, then have it signed by an authorized
representative of your institution, and return it to me. Upon receipt of that
confirmation I will forward the material(s) to you.

[Note: Other paragraphs discussing the relevant literature, the nature of the
work, hazards relating to materials to be sent, etc., may be appropriate. These
will vary depending on the individual circumstance and the relationship between
the two parties previously established. Be sure to retain signed copy when
received and send a photocopy of the completed agreement to the University of
California Patent Administrator, Patent Office, Systemwide Administration, 2490
Channing Way, Third floor, Berkeley, California 94720.]

                                Sincerely yours,


                                                     ------------------------
Accepted:

         Research Investigator

         --------------------------
         Printed Name

         --------------------------
         Signature

         --------------------------
         Date

         Research University or
         Non Profit Institution

         --------------------------
         Printed Name


         --------------------------
         By

         --------------------------
         Date

<PAGE>
                            UNIVERSITY OF CALIFORNIA

                        Instructions for Standard Letter
                        Transmitting Biological Materials
                      To Industrial (for profit) Companies


     The attached letter agreement is authorized for use by the University of
California Principal Investigators when transmitting cell lines, plasmids and
like biological materials for non-commercial research purposes to scientists
employed by industrial (for profit) companies, and when no patent application
relating to those materials will be or has been filed.

When to use this letter:

1.      For the transmission of biological materials.

2. Materials must be used for research purposes only.

3. For profit taking corporations and companies.

4.      When no patent application relating to the materials will be or has been
        filed.

When not to use this letter:

1.      If a patent application has been filed on the materials, first contact
        the University Patent Office at (415) 642-5000 for instructions.

2.      For living plants or portions thereof. A separate "Testing Agreement for
        Plant Varieties" is available for use with these materials.

3.      For transmission of biological materials to scientists at other
        universities and non-profit institutions. A separate letter is used
        which is available from the University Patent Office.

4.      If a change in the wording of this standard letter is requested. Any
        changes in the wording of this standard letter must be reviewed and
        approved by the Director of the Patent, Trademark and Copyright Office
        before acceptance.

5.      If commercial use of the materials is intended, then contact the
        University Patent office because a commercial license may be required
        and releases from sponsors may be necessary.

How to use this agreement:

1.      Choose whether or not to include the phrase "our cooperative" in
        paragraph 2.

2.      Insert in paragraph 4 the amount of processing charge. If the material
        is to be shipped at no charge, insert the words "no charge."

3. Send the letter in duplicate to other scientists.

4.      Do not send biological materials until you receive the duplicate copy
        executed by both the scientist and the company representative.

5. Send a photocopy of the fully executed letter agreement to:

                  Roger G. Ditzel, Director
                  Patent, Trademark and copyright Office
                  University of California
                  2490 Channing Way, Third Floor
                  Berkeley, California 94720

JAN 83
<PAGE>
                        STANDARD LETTER FOR USE PRIOR TO
                      TRANSMISSION OF BIOLOGICAL MATERIALS
                         TO SCIENTIFIC INVESTIGATORS AT
                        INDUSTRIAL (for profit) COMPANIES

                               (Use UC Letterhead)

                                                                          (Date)

                                                                IN DUPLICATE

To:

This is to [acknowledge receipt of your letter] [confirm our telephone
conversation] in which you requested certain research materials developed in
this laboratory be sent to you for scientific research purposes. The materials
concerned, which belong to The Regents of the University of California, are:
(blank)

We will be pleased to permit your use of these materials by you and within your
company laboratory for [our cooperative] scientific research. However, before
forwarding them to you, we need your agreement and that of your company that the
materials will be received by you only for use in [our cooperative work]
[scientific research], they will not be used on any human subjects, that you and
your company will bear all risk to you or any others resulting from your use,
and that you or your company will not pass these materials, their progeny or
derivatives, on to any other party or use them for commercial purposes without
the express written consent of The Regents of the University of California. You
understand that no other right or license to these materials, their progeny or
derivatives, is granted or implied as a result of our transmission of these
materials to you.

These materials are to be used with caution and prudence in any experimental
work since all of their characteristics are not known. You understand these
materials are experimental in nature and, when delivered to you, are without
warranty of merchantability or fitness for any particular purpose, or any other
warranty of any kind.

As you recognize, there is a processing cost to us involved in providing these
materials to you. We will bill you for our processing costs, which will amount
to $(blank).

<PAGE>
Date
Page Two

If you agree to accept these materials under the above conditions, please sign
the enclosed duplicate copy of this letter, then have it signed by an authorized
representative of your company, and return it to me. Upon receipt of that
confirmation I will forward the materials(s) to you.

[Note: Other paragraphs discussing the relevant literature, the nature of the
work, hazards relating to materials to be sent, etc., may be appropriate. These
will vary depending on the individual circumstance and the relationship between
the two parties previously established. Be sure to retain signed copy when
received and send a photocopy of the completed agreement to the University of
California Patent Administrator, Patent office, Systemwide Administration 2200
University Avenue, Berkeley, California 94720.]

                                Sincerely yours,


                                                     ------------------------
Accepted:___________________________
          (Printed Name of Company)


Research Investigator               Authorized Company Representative


- --------------------------          ----------------------------------
Printed Name                        Printed Name

- --------------------------          ----------------------------------
Signature                           Signature

- --------------------------          ----------------------------------
Date                                Title

                                    ----------------------------------
                                    Date

JAN 83







[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission

                   RESEARCH, DEVELOPMENT AND OPTION AGREEMENT

     Research, Development and Option Agreement, dated as of June 9, 1987, by
and between Xoma Corporation ("Xoma"), a Delaware corporation, with its
principal place of business located at 2910 Seventh Street, Berkeley, California
94710, and Pfizer Inc. ("Pfizer"), a Delaware corporation, with its principal
place of business located at 235 East 42nd Street, New York, New York 10017.

     WHEREAS, Xoma has under development certain monoclonal antibody products
useful in the treatment of septic shock; and

     WHEREAS, Pfizer desires to fund certain Xoma research and development
regarding such products and desires an exclusive option to acquire certain
rights relating thereto pursuant to the terms and conditions provided therein.

     NOW, THEREFORE, the parties hereto agree as follows:

     1. CERTAIN DEFINITIONS

     For purposes of this Agreement the following definitions shall be
applicable:

     1.1 "Accepted Septic Shock Product" means any Other Septic Shock Product
for which Pfizer has acquired rights thereto under Section 4.2 hereof.

     1.2 "Affiliate" means (a) any company owned or controlled to the extent of
at least fifty percent (50%) of its issued and voting capital by a party to this
Agreement and any other company so owned or controlled (directly or indirectly)
by any such company or the owner of any such company, or (b) any partnership,
joint venture or other entity directly or indirectly controlled by, controlling,
or under common control of, to the extent of fifty percent (50%) or more of
voting power (or otherwise having power to control its general activities), a
party to this Agreement, but in each case only for so long as such ownership or
control shall continue.

     1.3 "Development Costs" means Xoma's costs and expenses related to the
development, research (including process research) and testing of any Subject
Product or any Accepted Septic Shock Product, in each case determined pursuant
to Exhibit A attached hereto and made a part thereof, together with Xoma's
expenses incurred in connection with the Review Panel as specified in Exhibit A.


<PAGE>


                                       -2-

     1.4 "Development Plan" means (a) the preclinical, clinical and process
development program and budget of estimated Development Costs through PLA
Submission for the E5 Product as set forth in Exhibit B, attached hereto and
made a part hereof, together with such further modifications as shall be
mutually agreed upon between Pfizer and Xoma, and (b) any subsequent Development
Plans (comparable in scope and content to the plan for the E5 Product) for any
Other Antibody Product as agreed upon between Pfizer and Xoma pursuant to
Section 4.1 hereof.

     1.5 "E5 Product" means any product for human and/or animal therapeutic or
prophylactic use, now or hereafter developed by Xoma, which is produced (or
susceptible of being produced) from or incorporates any antibody (including
Fragments thereof as hereinafter defined) secreted from the E5 Cell Line (as
hereinafter defined) or any other cell line capable of producing said antibody,
or which product is chemically, organically, biologically or synthetically
derived from or based upon any such antibody, in each case either alone or in
combination with any other therapeutic agent. For purposes of this Section 1.5,
the term "Fragments" shall mean any part or parts of any said antibody
chemically, biologically or organically obtained from said antibody, or
synthetically produced, and which mimics the biological behavior of said
antibody. For purposes of this Section 1.5, the term "E5 Cell Line" shall mean
the cell line described as a murine hybridoma as identified by American Type
Culture Collection No. HB 9081 and mutants and genetically manipulated variants
thereof.

     1.6 "FDA" means the United States Food and Drug Administration or any
successor governmental agency performing similar functions.

     1.7 "License Agreement" means the agreement so named of even date herewith
between Pfizer and Xoma.

     1.8 "Other Antibody Product" means any product for human and/or animal
therapeutic or prophylactic use, now or hereafter developed by Xoma, which is
produced (or susceptible of being produced) from or incorporates any antibodies
(including Fragments thereof as hereinafter defined) secreted from the J5D4 Cell
Line and/or the PCB5 Cell Line (as hereinafter defined) or any other cell lines
capable of producing any such antibodies, or which product is chemically,
organically, biologically or synthetically derived from or based upon any such
antibodies, in each case either alone or in combination with any other
therapeutic agent. For purposes of this Section 1.8, the term "Fragments" shall
mean any part or parts of any said antibodies chemically, biologically or
organically obtained from said antibodies, or synthetically produced, and


<PAGE>


                                       -3-

which mimics the biological behavior of said antibodies. For purposes of this
Section 1.8, the term "J5D4 Cell Line" shall mean the cell line described as a
murine hybridoma as identified by American Type Culture Collection No. HB 9083
and mutants and genetically manipulated variants thereof; and the term "PCB5
Cell Line" shall mean the cell line described as a murine hybridoma as
identified by American Type Culture Collection No. HB 8909 and mutants and
genetically manipulated variants thereof.

     1.9 "Other Septic Shock Product" means any product, now or hereafter
developed by Xoma, for the treatment, cure or prevention of Septic Shock, other
than any E5 Product or any Other Antibody Product.

     1.10 "Patents" means all Xoma patents listed in Exhibit C, annexed hereto
and made a part hereof, and any patents which may issue from the applications
listed in Exhibit C, in each case together with any divisionals, continuations,
continuations-in-part, reissues, patents of addition or extensions thereof.

     1.11 "PLA" means a Product License Application or such other application as
shall be required to obtain Product Approval for any Subject Product.

     1.12 "PLA Submission" means the submission to FDA by Xoma of a PLA which
has been prepared in good faith by Xoma in a reasonable manner to comply with
FDA requirements necessary to obtain Product Approval.

     1.13 "Product Approval" means final FDA approval to market commercially in
the U.S.A. the specified product for use in humans.

     1.14 "Review Panel" means a panel of three persons to advise Xoma as
provided herein. Such panel, to be appointed by Xoma with Pfizer's approval,
shall consist of an immunotoxicologist, a physician experienced in clinical
research, and an expert in FDA regulatory requirements for biologicals. Xoma
may, upon notice to Pfizer, remove members from the panel at any time for
reasonable cause provided that it fills any vacancy with persons reasonably
acceptable to Pfizer as promptly as reasonably practicable.

     1.15 "Security Agreement" means the agreement so named referred to in
Section 11 hereof.

     1.16 "Septic Shock" means endotoxin mediated complications of gram negative
bacterial sepsis.



<PAGE>


                                       -4-

     1.17 "Subject Product" means any E5 Product and any Other Antibody Product
for which Pfizer has exercised its option under Section 4.1. The E5 Product
shall be the initial Subject Product.

     1.18 "Supply Agreement" means the agreement so named of even date herewith
between Pfizer and Xoma.

     1.19 "Technical Information" means all of Xoma's trade secrets,
information, and know-how, now owned, licensed or controlled or hereafter
acquired, developed, owned, licensed or controlled by Xoma or any of its
Affiliates during the term of this Agreement, with respect to: (i) the medical,
clinical, toxicological or other scientific data or information relating to any
specified product (including, without limitation, pre-clinical and clinical
data, notes, reports, models, and samples) and (ii) the manufacture, production,
and purification procedures and processes, as well as analytical methodology,
used in the testing, assaying, analysis, production, and packaging of any
specified product. Technical Information shall also include: (i) Xoma's actual
cell lines and other biological materials and substances for any specified
product and (ii) Xoma's other information and non-patent proprietary rights (to
the extent not already included in this definition of Technical Information)
with respect to any specified product.

     1.20 "Territory" means all countries of the world.

     1.21 "University of California License" means the License Agreement For
Monoclonal Antibodies to Gram Negative Sepsis-Related Bacteria and Human
Diagnostics and Therapeutics Derived Therefrom, effective September 3, 1986,
between Xoma and The Regents of the University of California.

     2. XOMA REPRESENTATIONS, WARRANTIES AND COVENANTS

     Xoma hereby represents, warrants and covenants to Pfizer as follows:

     2.1 Xoma has the corporate power and authority to execute and deliver this
Agreement, the License Agreement and the Supply Agreement and perform its
obligations hereunder and thereunder, and the execution, delivery and
performance of this Agreement, the Supply Agreement and the License Agreement
have been duly and validly authorized by Xoma, and upon execution and delivery
by Pfizer, this Agreement, the Supply Agreement and the License Agreement will
constitute legal, valid and binding agreements of Xoma, enforceable in
accordance with their respective terms.


<PAGE>


                                       -5-

     2.2 Except to the extent Xoma has licensed patents or applications under
the University of California License, Xoma is the legal and equitable owner of
the Patents and applications listed on Exhibit C hereto, and, except for such
Patents, there are no other patents issued in any country in the Territory and
no other patent applications filed in any country therein, in each case owned or
filed by Xoma or any of its Affiliates relating to the E5 Product or any Other
Antibody Product or methods of use or manufacturing processes thereof. Xoma has
no knowledge of any fact which would cast doubt on the validity of any of the
Patents which have been issued as of this date.

     2.3 Xoma has not granted to any third party any rights or interests to the
Patents, the E5 Product, any Other Antibody Product, any Other Septic Shock
Product, or to Technical Information (as it relates to any of the foregoing) in
each case for human or animal therapeutic or prophylactic use, and neither the
execution and delivery of this Agreement, the Supply Agreement or the License
Agreement, nor consummation of the transactions contemplated hereunder or
thereunder, requires Xoma or any of its Affiliates to obtain any permits,
authorizations or consents under current law from any governmental body (except
for health approvals or governmental regulations necessary to sell such
products) or from any other person, firm or corporation under any existing
agreement to which Xoma or any of its Affiliates may be a party, and such
execution, delivery and consummation will not result in the breach of or give
rise to any termination of any agreement or contract to which Xoma or its
Affiliates may be a party or which otherwise relates to the Patents, the E5
Product, any Other Antibody Product, any Other Septic Shock Product, or any
Technical Information relating to any of the foregoing. Neither Xoma nor any of
its Affiliates after the date hereof shall enter into any agreement or take or
fail to take any action which shall restrict its legal right to grant to Pfizer
the rights and licenses contemplated under this Agreement or the License
Agreement.

     2.4 As of the date hereof, the University of California License is in full
force and effect and Xoma is in compliance in all material respects with all of
its obligations thereunder; Xoma has heretofore delivered to Pfizer a true and
complete copy thereof and there have been no amendments or modifications
thereof. So as not to adversely affect Pfizer rights hereunder or under the
License Agreement, Xoma agrees during the term of this Agreement not to take any
actions to terminate or restrict its rights under the University of California
License as it relates to the E5 Product, Other Antibody Products, Other Septic
Shock Products, or Technical Information relating thereto and to discharge all
of Xoma's material obligations and responsibilities thereunder, including,
without


<PAGE>


                                       -6-

limitation, making all required payments thereunder. In the event Xoma shall
receive any notice of default under the University of California License, Xoma
shall promptly notify Pfizer.

     2.5 Xoma has no knowledge as of the date of this Agreement of any material
information, not heretofore disclosed to Pfizer, relating to the potential
safety or efficacy of the E5 Product.

     2.6 Xoma shall take all reasonable steps and pay all necessary expenses to
prosecute the patent applications listed in Exhibit C unless Xoma, in
consultation with Pfizer, shall in good faith determine that it is not in the
best interests of both parties for Xoma to continue the prosecution of any
pending application. Xoma also shall take all reasonable steps and pay all
expenses necessary to maintain for the full life thereof all Patents unless
Xoma, in consultation with Pfizer, shall in good faith determine that it is not
in the best interests of both parties for Xoma to take such action or make such
payments. Xoma shall keep Pfizer fully informed as to the status of all pending
applications and the issuance of any such patents.

     3. PFIZER REPRESENTATIONS AND WARRANTIES

     Pfizer hereby represents and warrants to Xoma as follows:

     3.1 Pfizer has the corporate power and authority to execute and deliver
this Agreement, the Supply Agreement and the License Agreement and perform its
obligations hereunder and thereunder, and their execution, delivery and
performance have been duly and validly authorized by Pfizer, and upon execution
and delivery by Xoma, this Agreement, the Supply Agreement and the License
Agreement will constitute legal, valid and binding agreements of Pfizer,
enforceable in accordance with their respective terms.

     3.2 Neither the execution and delivery of this Agreement, the Supply
Agreement or the License Agreement, nor consummation of the transactions
contemplated hereunder or thereunder, requires Pfizer to obtain any permits,
authorizations or consents from any governmental body (except for health
approvals or governmental registrations necessary to sell the products
contemplated therein) or from any other person, firm or corporation, and such
execution, delivery and consummation will not result in the breach of or give
rise to any termination of any agreement or contract to which Pfizer may be a
party.


<PAGE>


                                       -7-

     4. PFIZER OPTIONS

     4.1 Other Antibody Products. Xoma hereby grants to Pfizer the exclusive
option during the term of this Agreement to acquire exclusive worldwide rights
to each of the Other Antibody Products pursuant to the terms of the License
Agreement. At such time Xoma files any IND application with FDA for any Other
Antibody Product, Xoma shall give Pfizer a copy of such IND application together
with a summary of all material Technical Information (reasonably necessary for
Pfizer or any like person to make a reasonable scientific and technical
evaluation for the purpose of exercising the option hereunder) regarding such
Other Antibody Product. For a [*] period thereafter Xoma shall not (unless
Pfizer earlier declines) negotiate with any third party regarding such Other
Antibody Product, and as soon as possible, and in no event later than the end of
said [*] period, Pfizer shall notify Xoma whether Pfizer wishes to exercise its
option hereunder with respect to such Other Antibody Product. In the event
Pfizer exercises its option, such Other Antibody Product shall be automatically
included within the definition of "Product" under the License Agreement and
shall become a Subject Product for purposes of this Agreement. In addition, Xoma
shall promptly prepare and submit to Pfizer a reasonable Development Plan
including reasonable budget of estimated Development Costs through PLA
Submission for such Other Antibody Product. Such Development Plan shall be
consistent in scope and content with the E5 Development Plan and, together with
such modifications as shall be mutually agreeable, shall be reasonably agreed
upon by the parties within [*] of Pfizer's notice to Xoma of Pfizer's exercise
of its option hereunder regarding such Other Antibody Product. If Pfizer within
said [*] period shall decline to exercise its option or shall fail to respond to
Xoma, Xoma may develop and market such Other Antibody Product itself (directly
or through its dealers or distributors) or may offer such product to third
parties for [*] following such [*] period, provided that any terms agreed upon
with third parties, considered as a whole, are not (unless offered to Pfizer for
at least [*]) materially less favorable to Xoma than the terms contained in the
License Agreement. If Xoma has not in good faith elected to market such Other
Antibody Product or concluded an agreement with a third party within [*] of the
filing of the IND application, Pfizer's option hereunder for such product shall
be revived.

     4.2 Other Septic Shock Products. For 15 years from the date hereof, prior
to granting any rights to third parties during the term of this Agreement with
respect to any Other Septic Shock Products or deciding itself to develop and
market


<PAGE>


                                       -8-

any Other Septic Shock Products, Xoma shall first offer such rights to Pfizer.
Any such offer by Xoma to Pfizer shall include an identification of such Other
Septic Shock Product and initial pre-clinical test results (including some
demonstration of activity, and preliminary toxicology) for review by Pfizer. If
Pfizer and Xoma cannot negotiate an agreement within [*] of such offer, Xoma may
develop and market such Other Septic Shock Product itself (directly or through
its dealers or distributors) or may offer such product to third parties for [*]
following such [*] period, provided that the terms offered third parties,
considered as a whole, are not (unless offered to Pfizer for at least [*])
materially less favorable to Xoma than the terms offered by Pfizer. At the end
of such [*], if no such agreement has been concluded and Xoma has not decided to
proceed on its own, Pfizer's rights under this Section 4.2 regarding such Other
Septic Shock Product shall be revived.

     4.3 Comparable Other Antibody Products or Other Septic Shock Products.
Notwithstanding to the contrary any provisions of Section 4.1 or 4.2 hereof,
Xoma shall not market itself or enter into any arrangement or contract with any
third party granting rights to the marketing of any Other Antibody Product or
Other Septic Shock Product for which under Section 4.1 Pfizer has declined to
exercise its option thereunder or for which under Section 4.2 Pfizer and Xoma
have not entered into any agreement contemplated therein, unless such Other
Antibody Product or Other Septic Shock Product shall be substantially different
from and materially clinically superior to (for a clinically relevant
indication) any then existing Subject Product.

     5. RESEARCH AND DEVELOPMENT

     5.1 Xoma Development Efforts. Xoma shall use reasonable diligence to carry
out the Development Plan for each Subject Product in accordance with each such
Development Plan and within all agreed upon timetables therein. Any material
change in any Development Plan shall be agreed to between Xoma and Pfizer. Xoma
and Pfizer recognize that changes or modifications in each Development Plan
(including estimated budgets) will, in all likelihood, be required, and each
agrees to negotiate in good faith and in a reasonable manner to reach agreement
for any such changes or modifications. Xoma shall be solely responsible for the
conduct of all phases of each Development Plan, including but not limited to
clinical trials specified therein; provided, however, Xoma agrees to consult in
good faith with Pfizer and the Review Panel as provided in this Section 5
regarding each Development Plan.


<PAGE>


                                       -9-

     5.2 Review Panel. The Review Panel (constituted as specified in Section
1.14) will meet with Xoma, and with Pfizer if requested by Pfizer, on a
quarterly basis, or as may otherwise be agreed upon, to discuss and review each
Development Plan, the progress and activities carried out thereunder, and any
other scientific, medical, regulatory, or other matter which either Pfizer or
Xoma deems advisable.

     5.3 Funding of Development Costs. Pfizer agrees to reimburse Xoma for its
Development Costs (determined in accordance with Exhibit A) for each Subject
Product, provided such Development Costs shall in no event be greater than the
estimated Development Costs contained in the appropriate Development Plan as
agreed upon between Xoma and Pfizer. Based on the estimated annual budgets in
the Development Plan for each Subject Product, Pfizer shall make monthly
payments, payable on the first day of each month, for estimated Development
Costs to be incurred by Xoma for the ensuing month. Within 30 days after the end
of each calendar quarter Xoma shall prepare and send to Pfizer (i) an invoice of
actual Development Costs incurred by Xoma during the preceding calendar quarter
and (ii) a reconciliation with the estimated monthly payments made by Pfizer
during such quarter. In the event Pfizer's estimated payments for such quarter
shall be greater than the actual invoiced amount, such overpayment shall be
applied by Pfizer against subsequent monthly payments of estimated Development
Costs due to Xoma or, at Pfizer's option, Xoma shall remit such overpayment to
Pfizer. In the event the actual Development Costs for any quarter shall be
greater than Pfizer's estimated monthly payments for such quarter, subject to
the first sentence of this Section 5.3, Pfizer shall make appropriate payment to
Xoma within thirty (30) days of receipt of Xoma's invoice.

     Pfizer shall pay all Development Costs (in accordance with the terms of
this Agreement) incurred by Xoma (a) from January 1, 1987 through Product
Approval with respect to the E5 Product, (b) from the date of IND filing through
Product Approval with respect to other Subject Products, and (c) subsequent to
Xoma's internal identification of the product through Product Approval with
respect to any Accepted Septic Shock Product. With respect to Development Costs
for the E5 Product incurred by Xoma prior to the date of this Agreement for
which Pfizer is responsible as provided above, Pfizer will pay such Development
Costs (as specified in Exhibit B) within 30 days of invoice by Xoma.

     5.4 Disclosure of Technical Information. Xoma shall disclose to Pfizer
within 30 days of the date of execution of this Agreement and thereafter on at
least a quarterly basis all Technical Information on each Subject Product not
previously


<PAGE>


                                      -10-

disclosed to Pfizer; provided, however, until such time as Pfizer's rights of
termination under Section 6.1 hereof shall have lapsed, Xoma shall not be
required to disclose to Pfizer any Technical Information regarding manufacturing
of Subject Products. Nothing herein shall be deemed to require Xoma to disclose
to Pfizer any Technical Information which Xoma is, in good faith, contractually
prohibited from disclosing to third parties. All Technical Information disclosed
to Pfizer shall be subject to the provisions of Section 8 hereof.

     5.5 Audit of Development Costs. Xoma shall keep full and accurate books and
records of its Development Costs and determination thereof. Xoma shall permit
Pfizer, at Pfizer's expense, by independent certified public accountants
employed by Pfizer solely for this purpose and reasonably acceptable to Xoma, to
examine such books and records (as they relate to Development Costs) at any
reasonable time, but not later than five (5) years following the invoice to
Pfizer of such Development Costs. As a condition to such examination, the
independent public accountant selected by Pfizer shall execute a written
agreement, reasonably satisfactory in form and substance to Xoma, to maintain in
confidence all information obtained during the course of any such examination
except for disclosure to Pfizer as necessary for the above purpose. The opinion
of said independent accountants regarding such Development Costs shall be
binding on the parties hereto.

     5.6 Orphan Drug Designations. At Pfizer's expense, promptly after execution
of this Agreement Xoma shall transfer to Pfizer all of Xoma's interests and
rights to the FDA designation to the E5 Product as an "orphan drug" as evidenced
by FDA's letter to Xoma dated November 4, 1985 (provided Pfizer prepares the
requisite documents). Xoma shall execute such further notices or documents, as
Pfizer may reasonably request and at Pfizer's expense, to effectuate the change
in such designation (provided Pfizer prepares the requisite documents). In
addition, should Xoma obtain in the future any other similar designation for any
other Subject Products, Xoma will, likewise, transfer its rights thereto to
Pfizer; provided, however, Xoma shall not be required to make any such transfer
if Xoma itself shall then be in a position to directly and materially benefit
from the tax credits available thereunder. In the event Pfizer's rights or
licenses shall terminate hereunder or under the License Agreement (except in the
event of termination by Pfizer for Xoma's breach of Section 2.01 of the License
Agreement or as provided otherwise in the Security Agreement) regarding any
Subject Product (or former Subject Product) for which Pfizer holds any such
orphan drug or similar designation, Pfizer will, at its expense, promptly
transfer to Xoma the rights to such designation transferred to Pfizer.


<PAGE>


                                      -11-

     6. PFIZER PAYMENTS

     6.1 Initial Payment. In addition to any other payments provided for herein,
within ten (10) days hereof, Pfizer shall pay Xoma [*] of which [*] shall be in
consideration of the patent rights for the E5 Product granted to Pfizer under
the License Agreement and [*] shall be in consideration of the granting to
Pfizer of the option under Section 4.1 hereof to acquire a license to patent
rights regarding the Other Antibody Products. If the two-week IV toxicity study
of the E5 Product in monkeys (study no. 81611-T11) (a) is not completed within
nine months after the date hereof pursuant to the protocol heretofore agreed
upon with Pfizer, or (b) is completed pursuant to such protocol with results not
satisfactory to Pfizer (as it may reasonably determine in good faith), or (c)
for any reason shall not have commenced by September 30, 1987, then in any such
event Pfizer shall have the right, by notice given within 30 days thereof, to
demand return by Xoma of said [*] in which event Xoma shall promptly return to
Pfizer said [*] and this Agreement, the License Agreement, the Supply Agreement
and all other agreements contemplated herein or therein shall terminate. If Xoma
agrees that the results of such study are not satisfactory (as it may reasonably
determine in good faith), Pfizer may, as it may elect, alternatively demand the
return of [*], and Xoma shall promptly return to Pfizer said [*] and this
Agreement, the License Agreement the Supply Agreement and all other agreements
contemplated herein or therein shall continue in effect with the E5 Product
eliminated as a Subject Product hereunder and as a "Product" under the License
Agreement. In that event, the first Other Antibody Product for which Pfizer
exercises its option under Section 4.1 shall be treated as the initial Subject
Product for purposes of Section 6.2 (with changes in Section 6.2 to reflect
proper protocol numbers).

     6.2 Milestone Payments. In further consideration for Xoma's timely research
and development efforts hereunder, Pfizer shall pay Xoma the following amounts
within 30 days of completion of the applicable events with respect to the
initial Subject Product:

     (a) [*] - Upon completion (according to protocol no. 81612-P2B) prior to
[*] of first 100 evaluable patients (which fulfill statistical criteria for
protocol evaluation) with confirmed Gram Negative Sepsis; provided, (i) the
report thereof shall include efficacy and safety analysis by blinded group (to
be unblinded at Pfizer's option) with analyses of adverse drug experiences,
biochemical and hematological parameters, and analysis and listing of all deaths
(together with copies of all reports to FDA -- FD 1639 or substitute form), and
(ii) such report is received by Pfizer on or before [*];


<PAGE>


                                      -12-

     (b) [*] - Upon completion of Phase II trial according to protocol no.
81612-P2B and receipt by Pfizer of the complete final report thereon on or
before [*];

     (c) [*] - Upon PLA Submission to FDA on or before [*]; or [*] - upon PLA
Submission after [*] and on or before [*];

     (d) [*] - Upon Product Approval on or before [*]; or [*] - upon Product
Approval after [*] but on or before [*]*; or [*] - upon Product Approval after
[*] but on or before [*]; or [*] - upon Product Approval after [*] and on or
before [*].

It is understood that the provisions of Section 12.1 hereof shall not apply to
this Section 6.2.

     7. REGULATORY MATTERS

     7.1 Compliance. Xoma agrees that its conduct in performing its obligations
under this Agreement shall conform in all material respects to all applicable
laws and regulations of the U.S. and foreign governments (and political
subdivisions thereof).

     8. PROPRIETARY RIGHTS AND CONFIDENTIAL INFORMATION

     8.1 Proprietary Riqhts. Except as expressly provided to the contrary
herein, in the License Agreement or the Security Agreement, all proprietary
rights, title, and interest with respect to E5 Products, Other Antibody
Products, Other Septic Shock Products, Subject Products, Accepted Septic
Products, Patents and Technical Information shall be and remain solely in Xoma.

     8.2 Confidential Information. Pfizer and its Affiliates shall keep
confidential and not use, except as provided herein, in the License Agreement,
Supply Agreement or as contemplated in the Security Agreement, all Technical
Information supplied in writing (or if orally, as confirmed in writing) by Xoma
during the term of this Agreement and for ten (10) years after termination or
expiration hereof; provided, however, that the foregoing obligations of
confidentiality and non-use shall not apply to the extent that any Technical
Information is demonstrated by written records to be (a) already known to Pfizer
or its Affiliates at the time of disclosure hereunder or is hereafter developed
by Pfizer or its Affiliates in the course of work entirely independent of any
disclosure hereunder; or (b) publicly known prior to or after disclosure


<PAGE>


                                      -13-


hereunder other than through acts or omissions of Pfizer or its Affiliates; or
(c) disclosed in good faith to Pfizer or its Affiliates under a reasonable claim
of right of which Pfizer is not aware of any dispute; or (d) disclosed to third
parties by Pfizer under a secrecy agreement with essentially the same
confidentiality provisions provided herein in connection with the exercise of
its rights under the License Agreement (to the extent permitted therein) or the
Supply Agreement. In addition, disclosure may be made (i) to governmental
agencies to the extent required or desirable to secure governmental approval for
marketing of any Subject Product and (ii) to pre-clinical and clinical
investigators where necessary or desirable for their information to the extent
normal and usual in the custom of the trade and under a secrecy agreement with
essentially the same confidentiality provisions contained herein. All Technical
Information heretofore disclosed in writing by Xoma shall be deemed to have been
disclosed under this Agreement and shall be subject to the provisions of this
Section 8.2.

     9. INDEMNIFICATION

     9.1 Each party (the "Indemnifying Party") will indemnify the other (the
"Indemnified Party") from damages, settlements, costs, legal fees and other
expenses incurred in connection with a claim against the Indemnified Party based
on any action or omission (including, without limitation, resulting from
clinical trials) of the Indemnifying Party or its agents or employees related to
the obligations of the Indemnifying Party under this Agreement, provided,
however, that the foregoing shall not apply (i) if the claim is found to be
based upon the negligence, recklessness or willful action or inaction of the
Indemnified Party, or (ii) if the Indemnified Party fails to give the
Indemnifying Party prompt notice of any claim it receives and such failure
materially prejudices the Indemnifying Party, or (iii) solely to the extent of
indemnification for legal fees and disbursements of counsel of the Indemnified
Party, unless the Indemnifying Party is given the opportunity to control defense
of such action, or (iv) unless the Indemnifying Party is given the opportunity
to approve any settlement, which approval shall not be unreasonably withheld;
and provided further that, except in the event of a material conflict of
interest, the Indemnifying Party shall not be liable for attorney's fees of the
Indemnified Party after assuming control of the defense or settlement.

     10. TERM AND TERMINATION

     10.1 Term. This Agreement shall be effective as of the


<PAGE>


                                      -14-

date first set forth above and shall remain in effect until termination or
expiration of the License Agreement or other earlier termination pursuant to
Sections 6.1, 10.2 or 10.3 hereof.

     10.2 Termination in Part.

     (a) Pfizer shall have the right, upon ninety (90) days' prior notice to
Xoma, at any time and from time to time, without cause and at Pfizer's sole
discretion, to terminate this Agreement with respect to any Subject Product in
which case such Subject Product shall be automatically deleted as a "Product"
under the License Agreement and shall no longer be a Subject Product hereunder.

     (b) Upon any partial termination under Section 10.2(a), Pfizer shall only
be responsible for Development Costs incurred by Xoma with respect to such
Subject Product during the ninety (90) day period following the date of notice
of termination as well as reasonable termination costs incurred by Xoma
thereafter (including reasonable severance payments and reasonable buy-outs of
preexisting contracts reasonably entered into); provided, however, Xoma shall
use best efforts to mitigate and control such termination costs.

     (c) In the event of partial termination of this Agreement under Section
10.2 with respect to any Subject Product, Pfizer will have no rights and Xoma
will have no obligations with respect thereto under this Agreement, the License
Agreement, or the Supply Agreement (except for obligations under Sections 8.2
and 9.1 hereof), and Pfizer will immediately return to Xoma all Technical
Information relating thereto.

     10.3 Termination in Full.

     (a) This Agreement shall terminate in full as provided in Section 6.1
hereof.

     (b) At any time, upon ninety (90) days' prior notice to Xoma, Pfizer shall
have the right, without cause at Pfizer's sole discretion, to terminate in full
this Agreement, whereupon this Agreement together with the License Agreement and
Supply Agreement shall terminate ninety (90) days after the date of such notice.

     (c) If either Pfizer or Xoma materially breaches or defaults in the
performance or observance of any of the provisions of this Agreement and such
breach or default is not cured within ninety (90) days or, in the case of
failure to pay any amounts due hereunder, sixty (60) days after the giving of
notice by the other party specifying such breach or default, the other party
shall have the right to terminate this Agreement in full upon a further thirty
(30) days' notice.

<PAGE>


                                      -15-

     (d) Upon any termination under Section 10.3(b) hereof or Section 9.02 of
the License Agreement, Pfizer shall be responsible for all Development Costs
incurred by Xoma with respect to Subject Products during the ninety (90) day
period following the date of notice of termination as well as reasonable
termination costs incurred by Xoma thereafter (including reasonable severance
payments and reasonable buy-outs of preexisting contracts reasonably entered
into); provided, however, Xoma shall use best efforts to mitigate and control
such termination costs.

     (e) In the event of termination in full of this Agreement under Sections
6.1 or 10.3 hereof, subject to Section 9.05 of the License Agreement Pfizer will
have no rights and Xoma will have no further obligations under this Agreement,
the License Agreement, or the Supply Agreement (except for obligations under
Section 8.2 and 9.1 hereof or under the Security Agreement), and Pfizer will
immediately return to Xoma all Technical Information.

     10.4 Effects of Termination. Termination of this Agreement for any reason
shall be without prejudice to:

     (a) The rights and obligations of the parties provided in Sections 8.2 and
9.1 hereof;

     (b) Xoma's right to receive all payments accrued under Sections 5.3 and 6.2
hereof prior to the effective date of such termination; and

     (c) Any other remedies which either party may otherwise have.

     11. SECURITY AGREEMENT

     Certain of Xoma's obligations under this Agreement are secured pursuant to
the terms of a Security Agreement, dated the date hereof, between Xoma and
Pfizer, and reference is made to said Security Agreement for a description of
the terms thereof. Notwithstanding to the contrary any provision of this
Agreement, nothing herein shall be deemed to restrict, limit, modify or alter
any of Pfizer's rights under the Security Agreement or derived upon or resulting
from the exercise of any rights or interests thereunder.

     12. MISCELLANEOUS

     12.1 Force Majeure. No party shall be liable for failure of or delay in
performing obligations set forth in this Agreement, and no party shall be deemed
in breach of its obligations, if such failure or delay is due to natural
disasters or any causes reasonably beyond the control of such party.


<PAGE>


                                      -16-

     12.2 Assignment. This Agreement may not be assigned by either party without
the prior consent of the other party; provided, however, (a) either party may
assign this Agreement to any entity which acquires substantially all of its
assets and business, and (b) Pfizer may assign this Agreement, in whole or in
part, to any Affiliate of Pfizer.

     12.3 Xoma Status. For the purpose of carrying out this Agreement Xoma shall
act as an independent contractor and not as partner, joint venturer, or agent
and shall not bind nor attempt to bind Pfizer to any contract.

     12.4 Notices. Any notice, consent or approval required under this Agreement
shall be in writing sent by registered certified airmail, postage prepaid, or by
telex or cable (confirmed by such registered or certified mail) and addressed as
follows:

If to Pfizer:                               If to Xoma:

Pfizer Inc.                                 Xoma Corporation
235 East 42nd Street                        2910 Seventh Street
New York, New York 10017                    Berkeley, California 94710

Telex: 420440                               Telex:  856-697

Attention: General Counsel                  Attention: Chairman

All notices shall be deemed to be effective on the date of mailing. In case any
party changes its address at which notice is to be received, written notice of
such change shall be given without delay to the other party.

     12.5 Entire Agreement. This Agreement together with the License Agreement,
Supply Agreement and Security Agreement (as well as any other documents referred
to herein or therein) set forth the entire agreement and understanding among the
parties hereto as to the subject matter hereof and has priority over all
documents, verbal consents or understandings made between Pfizer and Xoma before
the conclusion of this Agreement with respect to the subject matter hereof; none
of the terms of this Agreement shall be amended or modified except in writing
signed by the parties hereto.

     12.6 Waivers. A waiver by any party of any term or condition of this
Agreement in any one instance shall not be deemed or construed to be a waiver of
such term or condition for any similar instance in the future or of any
subsequent breach hereof.


<PAGE>


                                      -17-

     12.7 Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California without regard to the
conflicts of laws provisions thereof. The exclusive jurisdiction and venue of
any action with respect to this Agreement shall be the Superior Court of
California for the County of Alameda or the United States District Court for the
Northern District of California and each of the parties hereto submits itself to
the exclusive jurisdiction and venue of such courts for the purpose of any such
action. Service of process in any such action may be effected in the manner
provided in Section 12.4 for delivery of notices. The prevailing party in any
legal action to enforce or interpret this Agreement shall be entitled to
reasonable costs and attorney's fees.

     12.8 Remedies. The rights and remedies of a party set forth herein with
respect to failure of the other to comply with the terms of this Agreement
(including, without limitation, rights of full or partial termination of this
Agreement) are not exclusive, the exercise thereof shall not constitute an
election of remedies and the aggrieved party shall in all events be entitled to
seek whatever additional remedies may be available in law or in equity.

     12.9 Headings. Headings in this Agreement are included herein for ease of
reference only and shall have no legal effect.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first written above by their duly authorized officers.

                            XOMA CORPORATION

                            By /s/ Steven C. Mendell
                                   Chairman/ CEO

                            PFIZER INC.


                            By /s/William C. Steere
                                  Vice President


<PAGE>


                                    EXHIBIT A
                                DEVELOPMENT COSTS


<PAGE>


                                    EXHIBIT A
                                DEVELOPMENT COSTS

A.       Direct Research Expense

     Expenses for Subject Products specifically identifiable to a development
task. These expenses include:

     1.   Direct Labor Salaries and Benefits - Compensation cost per hour for
          actual hours worked on approved Pfizer projects (supported by time
          cards.) Examples include:

          Clinical Research Associates
          Technical Writers
          Data Entry
          Research Scientists (e.g. Toxicologist, Pathologist)
             Regulatory Affairs (e.g. Protocol Writing, Validation, Clinical
          Auditing, PDA Meetings)

     2.   Clinical Grants - Hospital expenses for approved studies paid to
          investigators. (Supported by approved agreements and expense
          reimbursements.)

     3.   Outside Laboratory Testing for approved Pfizer projects (supported by
          contracts and invoices). Examples include:

                           14 day Primate study
                           Primate retreatment study

     4.   Drug Expenses - Actual cost (as defined in Exhibit I of Supply
          Agreement) of drug distributed to investigators for use in studies.

     5.   Scientific Consultants - payments for time and expenses for work done
          on approved Pfizer projects (supported by invoices). Examples include:

                           Research Grants
                           Outside Analytical Support

     6.   Scientific Panels - payments for time and expenses for work on
          approved Pfizer projects (supported by invoices). Examples include:

                           Infectious Disease Panel
                           Advisory Panel

     7.   Other Direct Expenses - directly identifiable to an approved task
          (supported by invoices or receipts). Examples include:

                           Travel and Entertainment
                           Supplies, printing and duplicating
                           Testing
                           Postage, freight
                                    Routine patent maintenance fees and routine
                           ordinary expenses for outside professional services
                           for preparation of filing of patent applications
                           (uncontested) reasonably allocated to Subject
                           Products.


<PAGE>


EXHIBIT A
DEVELOPMENT COSTS
PAGE -2-

B.       Indirect Research Expenses

         Costs incurred in the support of direct research activities for Subject
         Products but which are not directly identifiable to development tasks.
         These costs include:

         1.       Indirect Labor Salaries and Benefits - Compensation cost for
                  supervisors, managers, clerks and secretaries in support of
                  direct labor. Charges should be supported by time cards or
                  allocated in the same ratio as direct labor for such
                  department or group. Examples include:

                           Clinical Research Department Manager
                           Clinical Research Asst Manager
                           Business Manager
                           Project Manager
                           Secretarial and Clerical support

         2.       Scientific Consultants - payments for time and expenses based
                  on a mutually agreeable per cent of charges (supported by
                  invoices and expense reimbursements).

         3.       Facilities - Equipment Rental, Depreciation, Utilities,
                  Security and Maintenance costs. Charges to Pfizer projects
                  will be allocated in the same ratio as Direct Labor Hours by
                  department. Machinery or Equipment purchases over $250,000 are
                  subject to Pfizer approval.

         4.       Other Indirect Costs - Other expenses in support of Direct
                  Research activities to be allocated in the same ratio as
                  Direct Labor. Examples include:

                           Research materials
                           Supplies
                           Services
                           Assay Validation

         5.       Product Liability Insurance - Allocated as a per cent of the
                  total number of patients being treated with drug (supported by
                  invoices and patient count).


<PAGE>


                                    EXHIBIT B
                               E5 DEVELOPMENT PLAN


<PAGE>


                           "CLINICAL DEVELOPMENT PLAN
                          XOMA E5 ANTIENDOTOXIN MURINE
                              MONOCLONAL ANTIBODY"


<PAGE>


INTRODUCTION

Gram-negative sepsis has become a major cause of morbidity and mortality in the
United States during the last 30 years. Current incidence in the U.S. is
estimated at approximately 200,000 cases per year with a mortality of 20-50%.
Clinical studies over the last decade have shown that new developments in
antimicrobial therapy have done little to change mortality. The ability to
specifically neutralize endotoxin with XOMA's E5 antiendotoxin antibody
represents the first major therapeutic advance since the introduction of
antibiotics in the 1940's and holds new promise for significant reduction in
mortality and morbidity in gram-negative infection.

I.       Overall Development Objectives:

         -        Generate adequate data for a PLA for FDA approval.
         -        [*]
         -        [*]
         -        [*]
         -        [*]
         -        [*]

                                        1


<PAGE>


<TABLE>
II.      Tabular Summary of Clinical Studies
<CAPTION>
                                                                                            Budget - Total Hospital
                                                                                                    Expenses Only

Study No.         Phase        Site                          Objective                           1987     1988     1989
TOTAL
<S>               <C>          <C>                           <C>                                 <C>      <C>      <C>
<C>
81612-P1A         I            St. Louis Univ.               Safety & Pharmaco                   [*]      [*]      [*]
[*]
                                    kinetics
81612-P2A         II           St. Louis Univ.               Safety & Efficacy                   [*]      [*]      [*]
[*]
81612-P2B         II/III       Multicenter                   Safety & Efficacy                   [*]      [*]      [*]
[*]
A                 II/III       Multicenter                   Safety & Efficacy                   [*]      [*]      [*]
[*]
B                 II/III       Multicenter                   Safety & Efficacy                   [*]      [*]      [*]
[*]
C                 I/II         Multicenter                   Safety & Pharmaco-                  [*]      [*]      [*]
[*]
                                    dynamics
D                 I/II         Multicenter                   Safety & Pharmaco-                  [*]      [*]      [*]
[*]
                                    dynamics
E                 II/III       Multicenter                   Safety & Efficacy                   [*]      [*]      [*][*]
</TABLE>

*Completed study funded by XOMA

                                        2

<PAGE>


III.     Individual 1987 Study Descriptions

         Study Number and Name:     81612-P1A:[*]

         Design:                            [*]

         Objective:                         [*]

         Rationale:                         [*]

         Number of Patients:                [*]

         Dosages:                           [*]

         Conclusions:                       [*]

         Estimated Completion:      [*]

                                        3

<PAGE>



Study Number and Name:     81612-P2A:[*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Number of Centers:                  [*]

Dosage:                             [*]

Patient Accrual Rate:      [*]

Estimated Start:           [*]

Estimated Completion:      [*]

                                        4

<PAGE>


Study Number and Name:     81612-P2B: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Number of Centers:                  [*]

Number of Centers to
be Added:                           [*]

Patient Accrual Rate:               [*]

Statistical Plan:                   [*]

Dosages:                            [*]

Estimated Start:                    [*]

Estimated Completion:               [*]

                                        5

<PAGE>


Study Number and Name:     Study A: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Centers
Planned:                            [*]

Patient Accrual Rate:               [*]

Number of Patients:                 [*]

Dosage:                             [*]

Estimated start:                    [*]

Estimated Completion:               [*]

                                       -6-

<PAGE>


Study Number and Name:     Study B: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Number of Centers
Planned:                            [*]

Patient Accrual Rate:               [*]

Dosage:                             [*]

Estimated Start:                    [*]

Estimated Completion:               [*]

                                        7

<PAGE>


Study Number and Name:     Study C: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Number of Centers:                  [*]

Patient Accrual Rate:               [*]

Dosage:                             [*]

Estimated Start:                    [*]

Estimated Completion:               [*]

                                        8

<PAGE>


Study Number and Name:     Study D: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Number of Centers
Planned:                            [*]

Patient Accrual Rate:               [*]

Dosage:                             [*]

Estimated Start:                    [*]

Estimated Completion:               [*]

Patient Population:                 [*]

                                        9


<PAGE>


Study Number and Name:     Study E: [*]

Design:                             [*]

Objective:                          [*]

Rationale:                          [*]

Number of Patients:                 [*]

Dosage:                             [*]

Number of Centers:                  [*]

Patient Accrual Rate:      [*]

Estimated Start:           [*]

Estimated Completion:      [*]

                                       10


<PAGE>


<TABLE>
<CAPTION>
                                                   1987                1988               1989
PRECLINICAL           Pharm/Safety                 Q1     Q2    Q3     Q4    Q1     Q2    Q3     Q4     Q1    Q2
Q3                    Q4
<S>                   <C>                          <C>
                      [*]                          [*]
                      Toxicology
                      [*]                          [*]
                      Phase I                      COMPLETE
                      Phase II                     [*]
                      Multicenter                  [*]

CLINICAL              A                            [*]
                      B                            [*]
                      C                            [*]
                      D                            [*]
                      E                            [*]
</TABLE>

                                       11


<PAGE>


<TABLE>
                              XOMA E5 BUDGET DETAIL
                                 DIRECT EXPENSES

Direct expenses will be billed to Pfizer as the lesser of actual Costs or the
following maximums. Status against these maximums will be provided in the
quarterly reconciliations.

<CAPTION>
                                            1987                       1988                      1989
<S>                                         <C>                        <C>                       <C>
CLINICAL RESEARCH
Labor                                       [*]                        [*]                       [*]
Services                                    [*]                        [*]                       [*]
Supplies                                    [*]                        [*]                       [*]
Travel                                      [*]                        [*]                       [*]
Patents/Legal                               [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

PRECLINICAL
Labor                                       [*]                        [*]                       [*]
Services                                    [*]                        [*]                       [*]
Supplies                                    [*]                        [*]                       [*]
Travel                                      [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

PROCESS DEVELOPMENT
Labor                                       [*]                        [*]                       [*]
Services                                    [*]                        [*]                       [*]
Supplies                                    [*]                        [*]                       [*]
Travel                                      [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

TOTAL DIRECT EXPS                           [*]                        [*]                       [*]
</TABLE>



<PAGE>


<TABLE>
                              XOMA E5 BUDGET DETAIL
                              INDIRECT/G&A OVERHEAD

Indirect/G&A overhead expenses will be billed to Pfizer as the lesser of actual
cost or the following annual maximum. Status at these maximums will be provided
in the quarterly reconciliation

<CAPTION>
                                            1987                       1988                      1989
<S>                                         <C>                        <C>                       <C>
CLINICAL RESEARCH
Consulting                                  [*]                        [*]                       [*]
Indirect Labor/
Supplies/Legal/
Dept Exps                                   [*]                        [*]                       [*]
Regulatory Affairs                          [*]                        [*]                       [*]
Product Liability                           [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

PRECLINICAL RESEARCH
Second Generation                           [*]                        [*]                       [*]
Supplies/Travel                             [*]                        [*]                       [*]
Facilities                                  [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

PROCESS DEVELOPMENT
Supplies/Dept OH                            [*]                        [*]                       [*]
Facilities                                  [*]                        [*]                       [*]
TOTAL                                       [*]                        [*]                       [*]

TOTAL INDIRECT/G&A                          [*]                        [*]                       [*]
</TABLE>



<PAGE>


<TABLE>
                                 TOTAL EXPENSES
<CAPTION>
                                    1987             1988              1989             Total
<S>                                 <C>              <C>               <C>              <C>
CLINICAL                            [*]              [*]               [*]              [*]
PRECLINICAL                         [*]              [*]               [*]              [*]
PROCESS DEV                         [*]              [*]               [*]              [*]4
TOTAL EXPENSES                      [*]              [*]               [*]              [*]
</TABLE>



<PAGE>


<TABLE>
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1987
                                               TOTAL COSTS BY QUARTER
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     Q1           Q2            Q3           Q4           1987
<S>                                                  <C>          <C>           <C>          <C>          <C>

Preclinical
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

Process Development
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PROCESS DEVELOPMENT                            [*]          [*]           [*]          [*]          [*]

Clinical Research
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
  Patent/Legal                                       [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL CLINICAL RESEARCH                              [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>


<TABLE>
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1988
                                                 TOTAL COSTS BY QTR
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     Q1           Q2            Q3           Q4           TOTAL
<S>                                                  <C>          <C>           <C>          <C>          <C>
Preclinical
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

Process Development
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PROCESS DEVELOPMENT                            [*]          [*]           [*]          [*]          [*]

Clinical Research
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
  Patent/Legal                                       [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL CLINICAL RESEARCH                              [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>


<TABLE>
                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1989
                                               TOTAL COSTS BY QUARTER
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     Q1           Q2            Q3           Q4           1989
<S>                                                  <C>          <C>           <C>          <C>          <C>
Preclinical
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

Process Development
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PROCESS DEVELOPMENT                            [*]          [*]           [*]          [*]          [*]

Clinical Research
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
  Patent/Legal                                       [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL CLINICAL RESEARCH                              [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>


<TABLE>
                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1987
                                              TOTAL COSTS BY BENCHMARK
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     [*]          [*]           [*]          [*]          [*]
<S>                                                  <C>          <C>           <C>          <C>          <C>
Preclinical
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

Process Development
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PROCESS DEVELOPMENT                            [*]          [*]           [*]          [*]          [*]

Clinical Research
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
  Patent/Legal                                       [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL CLINICAL RESEARCH                              [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>


<TABLE>
                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1988
                                              TOTAL COSTS BY BENCHMARK
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     [*]          [*]           [*]          [*]          [*]
<S>                                                  <C>          <C>           <C>          <C>          <C>
Preclinical
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

Process Development
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PROCESS DEVELOPMENT                            [*]          [*]           [*]          [*]          [*]

Clinical Research
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
  Patent/Legal                                       [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL CLINICAL RESEARCH                              [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>


<TABLE>
                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                                   E5 BUDGET 1989
                                              TOTAL COSTS BY BENCHMARK
                                                       (000'S)
                                                       4/20/87
<CAPTION>
                                                     [*]          [*]           [*]          [*]          [*]
<S>                                                  <C>          <C>           <C>          <C>          <C>
Clinical Research:
  Labor                                              [*]          [*]           [*]          [*]          [*]
  Services                                           [*]          [*]           [*]          [*]          [*]
  Supplies                                           [*]          [*]           [*]          [*]          [*]
  Travel                                             [*]          [*]           [*]          [*]          [*]
    Total Direct Expense                             [*]          [*]           [*]          [*]          [*]
    Indirect R&D Expense                             [*]          [*]           [*]          [*]          [*]
    G & A Overhead                                   [*]          [*]           [*]          [*]          [*]
TOTAL PRECLINICAL                                    [*]          [*]           [*]          [*]          [*]

TOTAL PROJECT                                        [*]          [*]           [*]          [*]          [*]
</TABLE>


<PAGE>
<TABLE>
<CAPTION>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1987 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87
<S>                        <C>                               <C>              <C>              <C>

Clinical Research Detail:
         Labor -           St. Louis Study                    [*]
                           Multi Center Study                 [*]
                           Multicenter Study                  [*]

                           Sites/CRA                          [*]

                           CRA's Needed                       [*]
                             Salary                           [*]
                             Fringes                          [*]
                                                              [*]                                [*]

                                                              [*]
         Protocol Writer   [*]
         Data Input        [*]

                           Salary & Fringes                                                      [*]

Assay Validation, Documentation
                           Salary                             [*]
                           Fringes                            [*]                                [*]

Total Labor                                                                                      [*]

Services - St. Louis Study
                           Services                           [*]
                           Pharmacy                           [*]
                           Labs                               [*]
                                                              [*]
                                                              [*]                                [*]

                                                              Evaluable                          Non-Evaluable
Multicenter Study
         Business Agreements                                  [*]               [*]
         Endotoxin Levels
         Anti-Murine Levels                                   [*]               [*]
         Compliment Levels
         Misc.
                                                              [*]               [*]
         Patients                                             [*]               [*]              [*]


Multicenter Equivalency Study                                 [*]                                [*]
         Patients                                             [*]               [*]              [*]


</TABLE>

<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1987 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87
<TABLE>
<CAPTION>

                        Advisory Panel - [*] Individuals x [*] Meetings = [*]
Meeting Equiv.
<S>                                                 <C>                         <C>

                                                                                [*] Travel, Etc/Meeting
                                                                                [*] Compensation Meeting

[*]

                                                    E5 Time Spent
R. Greenberg Consulting                                                         [*]
L. Young Endotoxin Binding                                                      [*]
Infectious Disease Panel                                                        [*]

[*]
         Total Services
[*]

Supplies                                                                        [*]

         Drug Expenses - St. Louis  [*]

         Multicenter Efficacy
           QTR 1                                                                [*]
           QTR 2                                                                [*]
           QTR 3  [*]                                                           [*]
           QTR 4  [*]                                                           [*]
         Multicenter Equiv.

Total Supplies
[*]

Travel - Clinical Research Budget                                                                E5
                                                              Budget            E5%              Total
         Septic Shock Travel by CRA's                         [*]               [*]              [*]
         Dept. Mgr. Travel                                    [*]               [*]              [*]
         L. Rosendorf Travel                                  [*]               [*]              [*]

         Total Travel
[*]

Patent/Legal Fees
[*]

</TABLE>

<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1987 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87

<TABLE>
<CAPTION>
<S>                                 <C>    <C>      <C>    <C>        <C>       <C>                       <C>
Indirect R&D Expense

         L. Young Consulting                                                                              [*]
         L. Young Contract Grant                                                                          [*]

Clinical Research Budget:

         [*]

         Total R&D Expense                                                                                [*]

G & A Overhead

         Product Liability Insurance:

         U.S. Premiums     [*]

         Patients/Quarter: 1st      2nd     3rd      4th      Total

           E5                               [*]      [*]      [*]      [*]      [*]
           Other Septic Shock[*]    [*]     [*]      [*]      [*]
           [*]                      [*]     [*]      [*]      [*]      [*]
           [*]                      [*]     [*]      [*]      [*]      [*]
                  Total                                                         [*]
                  %E5                                                           [*]

         Premium Costs              [*]     [*]                        [*]

                  Total G & A Overhead                                                                    [*]
                  Total Clinical Research                                                                 [*]


</TABLE>

<PAGE>


                                  CONFIDENTIAL
                                XOMA CORPORATION
                           1987 BACK-UP BUDGET DETAIL
                                     (000'S)
                                    (4/20/87)

[*]

     Labor: Estimate of time required to accomplish toxicology studies and assay
            development.

            % Time on E5 Milestones

[*]


<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1987 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87


[*]:

         Labor:  Tech Development              [*]
                 Process Development           [*]
                 Analytical Biochemistry       [*]
                 In-Vitro                      [*]
                 Pilot Plant                                           [*]

Indirect:
         Supplies, Travel, [*]
         Facilities        [*]
                                                                       [*]
Total Process Development                      [*]


<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1988 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87

<TABLE>
<CAPTION>
Clinical Research Detail:
<S>                                                                    <C>             <C>               <C>

         Labor - Multicenter Equivalency                               [*]
         Documented Sepsis [*]
         Neutropenic       [*]
         Extended Administration                                       [*]
                                                                       [*]
         Sites/CRA                                                     [*]
         CRA's Needed      [*]                                                          [*]
         Protocol Writer/Data Input                                                                       [*]
         Assay Validation                                                               [*]
Total Labor                                                                                               [*]

Services:                                                              Evaluable          Non-Evaluable
         [*]                                                           [*]                [*]


</TABLE>
<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1988 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87

<TABLE>
<CAPTION>
<S>                                 <C>    <C>       <C>    <C>        <C>    <C>               <C>

Supplies:         Drug Expenses             QTR 1  [*]
                                                     QTR 2  [*]
                                                     QTR 3  [*]
                                                     QTR 4  [*]                                  [*]
Travel                                                                                           [*]
Legal/Patent                                                                                     [*]

Indirect R&D Expenses:
         L. Young Consulting & Contract                                [*]
         Clinical Research Budget                                               [*]
         Business Mgr. x [*]E5 Portion                                          [*]
         Project Mgr. & Support x [*] E5 Portion                       [*]
         Patent Control, Etc.                                                   [*]
         Assay Validation Overhead                                     [*]
         Regulatory Affairs x [*]                                               [*]
                                                                                                 [*]
G & A Overhead:
         Liability Insurance:
         U.S. Premiums              [*]
                                            [*]

Patients/Quarter           1st      2nd     3rd      4th      Total
         E5                                 [*]      [*]      [*]      [*]      [*]
         Other Septic Shock         [*]     [*]      [*]      [*]      [*]
         [*]                                [*]      [*]      [*]      [*]      [*]
         [*]                                [*]      [*]      [*]      [*]      [*]

                  Total                                                [*]
                  E5%                                                           [*]

Premium Costs                                                          [*]
         E5%                                                                    [*]

Total G & A Overhead                                                                    [*]

Total Clinical Research                                                                 [*]



</TABLE>
<PAGE>


                                  CONFIDENTIAL
                                XOMA CORPORATION
                           1988 BACK-UP BUDGET DETAIL
                                     (000'S)
                                     4/20/87

Process Development Detail:

         Labor:   [*]
                           [*]

Supplies                                    [*]

Travel                                      [*]

Indirect R & D Expense:
         Facilities                         [*]
         Dept. Overhead                     [*]                          [*]

Total Process Development                   [*]



<PAGE>



                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1988 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87

<TABLE>
<CAPTION>
<S>                                 <C>                                                        <C>

Preclinical Detail:

         Labor:                     Finalize assays and primate retreatment work.
                                    Toxicology/Assay                   [*]                       [*]

         Services:                  Consultants                                                  [*]

Indirect R & D Expense:

         Second Generation [*]      [*]
         Toxicology/Assay Supplies, etc.                               [*]
         Toxicology/Assay Facilities                                   [*]
                                                                                                 [*]
Total Preclinical                                                                                [*]



</TABLE>
<PAGE>


                                                    CONFIDENTIAL
                                                  XOMA CORPORATION
                                             1989 BACK-UP BUDGET DETAIL
                                                       (000'S)
                                                       4/20/87
<TABLE>
<CAPTION>

<S>                        <C>                      <C>                               <C>                <C>

Clinical Research Detail:

         Labor             [*]                       [*]
                           [*]                       [*]
                                                     [*]
         Sites/CRA                                   [*]
         CRA's Needed      [*]                       [*]
         Data Input                                  [*]
Total Labor                                                                                               [*]

Services:                                            Evaluable                          Non-Evaluable
                                                     [*]                                [*]

[*]
[*]

Supplies:                  Drug Expenses    [*]

Travel:                    CRA                                                                            [*]

Indirect                   Research Expenses:                                                             [*]
                           Clinical Research Budget                                                       [*]
                           Regulatory Affairs/Proj. Mgr./Etc.                                             [*]

G & A Overhead:

         Liability Insurance [*]w/Drug                                                                    [*]
                           Total Clinical Research                                                        [*]



</TABLE>
<PAGE>


                                XOMA CORPORATION

                     1987 Preclinical Development Plan - E5
                                 April 20, 1987

[*]

         Labor                                       [*]
         Services & Overhead                         [*]
         Toxicology Studies                          [*]
         Drug & Supplies                    [*]

         TOTAL                                       [*]



<PAGE>


                                XOMA CORPORATION
                      1988 PRE-CLINICAL DEVELOPMENT PLAN E5
                                 APRIL 20, 1987

[*]
[*]
         Labor                      [*]
         Services                   [*]
         Indirect R&D               [*]
                                            [*]


<PAGE>


                           E5 PROCESS DEVELOPMENT PLAN
                                FEBRUARY 23, 1987

PHASE I BENCHMARKS [*]:                                           COMPLETION
         [*]

PHASE II BENCHMARKS [*]
         [*]

PHASE III [*]:
         [*]


<PAGE>


                                XOMA CORPORATION
                           E5 PROCESS DEVELOPMENT PLAN
                                 APRIL 20, 1987

PHASE I BENCHMARKS [*]:                                           COMPLETION
         [*]

PHASE II BENCHMARKS [*]:
         [*]

COSTS [*]:

         Labor & Fringes            [*]
         Supplies                           [*]
         Indirect R&D Expense       [*]
                                                     [*]

PHASE III [*]:

[*]

COSTS

         Labor & Fringes            [*]
         Supplies                           [*]
         Travel                             [*]
         Indirect R&D                       [*]


<PAGE>


                                          Development Costs for E5 Product
                                       January 1, 1987 through March 31, 1987:
                                                         [*]




<PAGE>
                                    EXHIBIT C
                                     PATENTS

I                           II                             III

US 06/855,878 (2)         US 06/781,242 (1)            US 06/855,878 (2)


                                                          
                                                           (Plus
                                                           foreign
                                                           filings
                                                           listed
                                                           under
                                                           Col
                                                           I)
AUSTRALIA 63236/86          US 06/855,878 (2)            US 07/036,766 (3)
CANADA 519,066              U.S. 07/036,766 (3)
EUROPE 86306420.0
  (10 EPO Countries)
IRELAND 2546/86
ISRAEL 79719
JAPAN 229481/86
KOREA 8128/86
NEW ZEALAND 217283
PHILLIPINES 34297
SOUTH AFRICA 86/7342
SPAIN 8602198
U.S. 07/036,766 (3)

(1) Filing Date 9/27/84 
(2) Filing Date 4/24/86 
(3) Filing Date 4/10/87



<PAGE>


                                LICENSE AGREEMENT

     AGREEMENT, dated as of June 9, 1987, between Xoma Corporation ("Xoma"), a
Delaware corporation having offices at 2910 Seventh Street, Berkeley, California
94710, and Pfizer Inc. ("Pfizer"), a Delaware corporation having offices at 235
East 42nd Street, New York, New York 10017.

     WHEREAS, Xoma and Pfizer have entered into a Research, Development and
Option Agreement ("R&D Agreement") of even date herewith relating to the
development of certain monoclonal antibody products; and

     WHEREAS, the R&D Agreement contemplates the granting by Xoma to Pfizer of
certain licenses under Xoma patents and technical information.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
provided herein Pfizer and Xoma hereby agree as follows:

                           SECTION 1.00 - DEFINITIONS

     For the purpose of this Agreement the following definitions shall be
applicable:

     1.01 "Affiliate" shall mean (a) any company owned or controlled to the
extent of at least fifty percent (50%) of its issued and voting capital by a
party to this Agreement and any other company so owned or controlled (directly
or indirectly) by any such company or the owner of any such company, or (b) any
partnership, joint venture or other entity directly or indirectly controlled by,
controlling, or under common control of, to the extent of fifty percent (50%) or
more of voting power (or otherwise having power to control its general
activities), a party to this Agreement, but in each case only for so long as
such ownership or control shall continue.

     1.02 "Combination Products" shall mean products which include any Licensed
Product and one or more other active ingredients.

     1.03 "Fiscal Year" shall mean (a) with respect to Pfizer's business
operations in the United States, each 12-month period beginning January 1 and
ending on the following December 31, or

<PAGE>

                                      -2-

(b) with respect to Pfizer's business operations outside the United States, each
12-month period beginning December 1 and ending on the following November 30.

     1.04 "Licensed Patents" shall mean (i) all patents listed in Appendix I,
annexed hereto and made a part hereof, and any patents which may issue from the
applications listed on Appendix I, in each case together with any divisionals,
continuations, continuations-in-part, reissues, patents of addition and
extensions thereof, and (ii) to the extent of Xoma's interest therein, all other
patents and applications in the Territory (as hereinafter defined) now owned or
controlled by, or licensed to, or hereafter during the term of this Agreement
owned or controlled by, or licensed to, Xoma or any of its Affiliates, in each
case relating to the Products or methods of use or manufacturing processes for
the Products, together with any divisionals, continuations,
continuations-in-part, reissues, patents of additions and extensions thereof.

     1.05 "Licensed Product" shall mean any Product, the manufacture, use or
sale of which would, in the absence of a license, infringe any of the Licensed
Patents or which utilizes Technical Information.

     1.06 "Net Sales" shall mean, with respect to each Licensed Product, gross
sales of Licensed Product sold by Pfizer, its Affiliates and sublicensees to
third parties, less the total of (a) to the extent included in gross sales,
ordinary and customary trade discounts actually allowed, (b) to the extent
included in gross sales, excise taxes, other consumption taxes, customs duty and
compulsory payments to governmental authorities actually paid or deducted to the
extent relating to sales of Licensed Products, and (c) amounts equivalent to 5%
of said gross sales as an allowance for all other discounts and expenses.

     1.07 "Payment Computation Period" shall mean (a) with respect to Pfizer's
business operations in the United States, each three (3) month period, or any
portion thereof, ending on the last day of March, June, September and December
of a given year, or (b) with respect to Pfizer's business operations outside the
United States, each three (3) month period, or any portion thereof, ending on
the last day of February, May, August or November of a given year.

     1.08 "Production Margin" shall mean with respect to each Licensed Product
the difference between Net Sales and Product Cost for such Licensed Product.

<PAGE>
                                       -3-

     1.09 "Product Cost" shall mean Pfizer's standard cost for purified active
bulk of Licensed Product, such standard cost determined according to Pfizer's
accounting standards which shall be in conformity with generally accepted
accounting principles consistently applied (and as described, in part, in a
letter from Pfizer to Xoma dated May 5, 1987). It is understood that during any
Payment Computation Period in which Pfizer is purchasing from Xoma 100% of
Pfizer's requirements pursuant to the Supply Agreement, such standard cost shall
be the price paid by Pfizer to Xoma for purified active bulk supplied by Xoma
thereunder. In addition such standard cost shall be the standard cost of Pfizer
or its Affiliate, as the case may be, which first produces or purchases said
purified active bulk.

     1.10 "Products" shall mean (i) any product, now or hereafter developed by
Xoma, which is produced (or susceptible of being produced) from or incorporates
any antibody (including Fragments thereof as hereinafter defined) secreted from
the E5 Cell Line (as hereinafter defined) or any other cell line capable of
producing said antibody, or which product is chemically, organically,
biologically or synthetically derived from or based upon any such antibody, in
each case either alone or in combination with any other therapeutic agent. For
purposes of this Section 1.10, the term "Fragments" shall mean any part or parts
of any said antibody chemically, biologically or organically obtained from said
antibody, or synthetically produced, and which mimics the biological behavior of
said antibody. For purposes of this Section 1.10, the term "E5 Cell Line" shall
mean the cell line described as a murine hybridoma as identified by American
Type Culture Collection No. HB 9081 and mutants and genetically manipulated
variants thereof; and (ii) any Other Antibody Product, as defined in the R&D
Agreement, for which Pfizer hereafter exercises its option under Section 4.1
thereof -- with respect to the foregoing clauses (i) and (ii), in each case
together with all pharmaceutical compositions and dosage units thereof.

     1.11 "Security Agreement" shall mean the agreement so named referred to in
Section 11.09 hereof.

     1.12 "Selected Countries" shall mean Japan, United Kingdom, France, Federal
Republic of Germany and Italy.

     1.13 "Septic Shock" shall mean endotoxin mediated complications of gram
negative bacterial sepsis.

     1.14 "Supply Agreement" shall mean the agreement so named of even date
herewith between Pfizer and Xoma.

<PAGE>
                                       -4-

         1.15 "Technical Information" shall mean all of Xoma's trade secrets,
information, and know-how, now owned, licensed or controlled by Xoma or its
Affiliates or hereafter acquired, developed, owned, licensed or controlled by
Xoma or any of its Affiliates (to the extent of Xoma or its Affiliates rights)
during the term of this Agreement, in each case with respect to (i) the medical,
clinical, toxicological or other scientific data or information relating to the
Products (including, without limitation, pre-clinical and trial data, notes,
reports, models, and samples) and (ii) the manufacture, production, and
purification procedures and processes, as well as analytical methodology, used
in the testing, assaying, analysis, production, and packaging of the Products.
Technical Information shall also include: (i) Xoma's actual cell lines and other
biological materials and substances for any of the Products and (ii) Xoma's
other information and non-patent proprietary rights (to the extent not already
included in this definition of Technical Information) with respect to the
Products. Any of the foregoing which Xoma in good faith is contractually
prohibited from disclosing to third parties shall not be included within the
definition of Technical Information.

     1.16 "Territory" shall mean Territory A and Territory B. "Territory A"
shall mean the United States of America, its territories and possessions, and
"Territory B" shall mean all countries of the world except for Territory A.

     1.17 "University of California License" shall mean the License Agreement
for Monoclonal Antibodies to Gram Negative Sepsis-Related Bacteria and Human
Diagnostics and Therapeutics Derived Therefrom, effective September 3, 1986,
between Xoma and The Regents of the University of California.

                  SECTION 2.00 - GRANT AND RELEASE OF LICENSES

     2.01 Subject to the terms hereunder, Xoma hereby grants to Pfizer, and
Pfizer hereby accepts: (a) except with respect to Xoma's rights under the
University of California License, an exclusive license under the Licensed
Patents to make, have made, use and sell Licensed Products for human and animal
therapeutic and/or prophylactic use; (b) except with respect to Xoma's rights
under the University of California License, an exclusive license to use in the
Territory all Technical Information in connection with the manufacture, use and
sale of Licensed Products for human and animal therapeutic and/or prophylactic
use; and (c) with respect to the University of California License, an exclusive
sublicense of all rights and licenses granted to Xoma under the University of
California License with respect to the Licensed Products for human and animal
therapeutic and/or prophylactic use in the Territory. Each of the foregoing
licenses or sublicenses includes the right by Pfizer to grant sublicenses.

<PAGE>
                                       -5-

     2.02 Notwithstanding the provisions of Section 2.01 hereof, Xoma retains
for itself with respect to Licensed Products those rights to Licensed Patents
and Technical Information which it had immediately prior to the execution of
this Agreement to the extent necessary to perform, and solely for the purpose of
performing, its obligations to supply Licensed Products under the Supply
Agreement so long as such agreement remains in effect.

     2.03 At any time Pfizer shall have the right, at Pfizer's sole discretion
upon 60 days' prior notice to Xoma, to release all licenses granted herein with
respect to Territory A or all countries in Territory B, as Pfizer may elect.

     2.04 Within three (3) months after the completion by Xoma of the clinical
studies pursuant to protocol no. 81612-P2B and the submission to Pfizer of the
final report thereon, Pfizer shall notify Xoma whether Pfizer intends to pursue
health registration in at least three Selected Countries other than Japan for
such Licensed Product under said protocol. If Pfizer does not intend to pursue
such registration, Pfizer shall promptly terminate its rights hereunder with
respect to such Licensed Product for all countries in Territory B, except for
Japan. If Pfizer shall not terminate its rights as aforesaid, Pfizer shall
diligently pursue in good faith the registration of said Licensed Product in at
least three Selected Countries (other than Japan).

     2.05 Within six (6) months after the completion by Xoma of the clinical
studies pursuant to protocol no. 81612-P2B and the submission to Pfizer of the
final report thereon, Pfizer shall notify Xoma whether Pfizer intends to pursue
health registration in Japan for such Licensed Product under said protocol. If
Pfizer does not intend to pursue such registration, Pfizer shall promptly
terminate its rights hereunder with respect to such Licensed Product for Japan.
If Pfizer shall not terminate its rights as aforesaid, Pfizer shall diligently
pursue in good faith the registration of such Licensed Product in Japan.

     2.06 In the event a Product described in Section 1.10, clause (i) shall no
longer be a Subject Product under the terms of the R&D Agreement as a result of
the provisions of the penultimate sentence of Section 6.1 of the R&D Agreement,
and an Other Antibody Product (as defined in the R&D Agreement) shall become the
initial Subject Product for purposes of Section 6.2 thereof, the provisions of
Sections 2.04 and 2.05 hereof shall become applicable to the first such Other
Antibody Product, provided the protocol referred to in Sections 2.04 and 2.05
hereof shall be the appropriate protocol for such Other Antibody Product, which
protocol shall be for a multi-center study similar in scope and size to protocol
no. 81612-P2B and designed to obtain sufficient safety and efficacy data for the
submission of a Product License Application to FDA.

<PAGE>
                                       -6-

                      SECTION 3.00 - ROYALTIES AND PAYMENTS

     3.01 In consideration of the licenses granted to Pfizer under Section 2.01
hereof, Pfizer shall pay to Xoma royalties based on the aggregate Production
Margin during each Fiscal Year for each Licensed Product. For purposes of
determining royalties, the E5 Product, J5D4, and PCB5 (as defined or described
in the Research and Development Agreement) as well as Combination Products of
each shall each be considered as separate Licensed Products. Royalties shall be
computed (a) separately for each Fiscal Year for each Licensed Product based on
the aggregate Production Margin thereof, (b) separately with respect to Net
Sales in Territory A and Territory B, and (c) with a different royalty rate
applicable to different increments of Production Margin for each such Licensed
Product.

Aggregate Production Margin for
Net Sales in Territory A
for Each Fiscal Year                                        Rate

[*]                                                         [*]
[*]                                                         [*]
[*]                                                         [*]
[*]                                                         [*]
[*]                                                         [*]
[*]                                                         [*]

Aggregate Production Margin For
Net Sales in Territory B For
Each Fiscal Year                                            Rate
[*]                                                         [*]
[*]                                                         [*]
[*]                                                         [*]

Example: Aggregate Product Margin for Net Sales in U.S.A. (Territory A) for
Fiscal Year [*] for E5 and [*] for J5D4 antibody. Royalties for U.S.A. sales of
E5 as follows:

E5 Product Margin                           Rate            Amount of Royalty
                                                            ($ millions)
[*]                                         [*]             [*]
[*]                                         [*]             [*]
[*]                                         [*]             [*]
                                                            [*]

<PAGE>
                                       -7-

         A similar separate computation would be made for J5D4 aggregate
         Production Margin for Net Sales in the U.S.A., and similar separate
         computations would be made for E5 and J5D4 for aggregate Production
         Margin of each for Net Sales in Territory B for each Fiscal Year.

     In the event Pfizer shall be selling a Combination Product containing one
or more other active ingredients which are not Licensed Products, then aggregate
Production Margin for such Combination Product shall be determined as follows:
(a) Net Sales for the Combination Product shall be determined as set forth in
Section 1.06 hereof; (b) Product Cost shall not be determined as provided in
Section 1.09 hereof, but rather shall be Pfizer's standard cost for the
Combination Product in finished packaged dosage form (determined according to
Pfizer's accounting standards which shall be in conformity with generally
accepted accounting principles), and (c) such Product Cost shall be subtracted
from such Net Sales of such Combination Product and the resulting difference
shall then be divided by one-half (1/2) which amount shall be the Production
Margin for such Combination Product for royalty purposes hereunder.

     Notwithstanding to the contrary the provisions of the immediately preceding
paragraph, if any Combination Product being sold by Pfizer contains, in addition
to a Licensed Product, another active ingredient which, as a single entity
agent, is being sold as a non-prescription (over-the-counter) drug in the United
States, then the immediately preceding paragraph shall not be applicable, and
Production Margin for such Combination Product shall be determined for each
country as hereinafter provided. In the event Pfizer or its Affiliates is
currently selling in such country the Licensed Product (contained in such
Combination Product) as a single entity, "Net Sales" of such Combination Product
for such country for any Payment Computation Period shall be computed as
follows: aggregate net sales during such period of the Licensed Product as a
single entity (determined in accordance with Section 1.06 hereof) shall be
divided by the aggregate number of grams of Licensed Product contained therein,
and the result thereof shall be multiplied by the aggregate number of grams of
Licensed Product contained in the Combination Product sold in such country
during such Payment Computation Period. In the event Pfizer or its Affiliates is
not currently selling in a country the Licensed Product as a single entity, "Net
Sales" of such Combination Product for such country shall be computed as
follows: aggregate net sales of the Combination Product (determined in
accordance with Section 1.06 hereof) shall be multiplied by a fraction, the
numerator being Pfizer's cost of the Licensed Product in such Combination
Product and the <PAGE>
                                      -8-

denominator being Pfizer's total cost of all active ingredients in such
Combination Product. Cost shall be based on Pfizer's accounting procedures which
are in accordance with generally accepted accounting practices. To determine
aggregate Production Margin for such Combination Product, Product Cost for the
Licensed Product contained in such Combination Product shall be determined as
provided in Section 1.09 hereof and Net Sales for such Combination Product shall
be determined as provided above. Royalties on aggregate Production Margin for
such Combination Product shall then be computed for Net Sales in Territory A and
Territory B at the respective rates provided above.

     3.02 The period of time royalties under Section 3.01 shall be payable shall
be determined on a country-by-country basis and on a Licensed
Product-by-Licensed Product basis and shall be for the longer of (a) fifteen
(15) years after first commercial sale after regulatory approval in such country
of the respective Licensed Product by Pfizer, its Affiliates or sublicensees, or
(b) until the last to expire of the Licensed Patents in such country which
includes claims directed toward a composition of matter, method of use, or
pharmaceutical dosage form for the particular Licensed Product sold, and,
thereafter, in the case of clause (a) or clause (b) Pfizer's license hereunder
with respect to Technical Information for such Licensed Product shall be a fully
paid-up license. Notwithstanding to the contrary any provision of Section 3.01,
in the event the Licensed Product sold by Pfizer in any particular country shall
not infringe any claim of any Licensed Patent in force in such country with
claims directed toward a composition of matter, method of use, or pharmaceutical
dosage form, then the royalty rates specified in Section 3.01 with respect to
Product Margin for Net Sales of such Licensed Product in such country shall each
be reduced by [*] to reflect the value to Pfizer of the Technical Information
for such Licensed Product.

     3.03 During each Fiscal Year, commencing with the first complete Fiscal
Year after the first commercial sale of the first Licensed Product sold in
Territory A, and so long as Licensed Patents covering at least one of the
Licensed Products sold therein shall be in effect in Territory A with claims
directed toward a composition of matter, method of use, or pharmaceutical dosage
form, Pfizer shall pay to Xoma minimum annual royalties under Section 3.01 with
respect to aggregate Net Sales of all Licensed Products in Territory A as
follows:

First Fiscal Year                           [*]
Second Fiscal Year                          [*]
Third through fifth Fiscal Year             [*]
Sixth and subsequent Fiscal Years           [*]
<PAGE>

                                      -9-

In addition, during each Fiscal Year, commencing with the first complete Fiscal
Year after the first commercial sale of the first Licensed Product sold in three
of the Selected Countries, and so long as Licensed Patents covering at least one
of the Licensed Products sold therein shall be in effect in such three Selected
Countries with claims directed toward a composition of matter, method of use, or
pharmaceutical dosage form, Pfizer shall pay Xoma minimum annual royalties under
Section 3.01 with respect to aggregate Net Sales of all Licensed Products in
Territory B as follows:

         First Fiscal Year                  [*]
         Second Fiscal Year                 [*]
         Third through fifth Fiscal Year    [*]
         Sixth and Subsequent Fiscal Years  [*]

In the event royalties actually paid under Section 3.01 hereof for any Fiscal
Year shall be less than the required minimum royalty for Territory A or
Territory B, as the case may be, Pfizer, within sixty (60) days after the end of
each Fiscal Year, shall pay such amounts to Xoma as necessary to insure that the
total of said royalties actually paid by Pfizer shall be not less than the
applicable minimum royalty.

     Notwithstanding to the contrary the foregoing, Pfizer shall not be required
to make minimum royalty payments and shall have no obligations under this
Section 3.03 (a) during such period of time Xoma shall fail for any reason,
including force majeure, to supply Pfizer with Products pursuant to the terms of
the Supply Agreement (provided in such case minimum royalty obligations shall be
reduced pro rata), or (b) for one complete Fiscal Year after the effective date
of any termination by Xoma of the Supply Agreement or (c) for one complete
Fiscal Year after the effective date of any termination of the Supply Agreement
by Pfizer as a result of the breach or default thereof by Xoma.

     3.04 Pfizer will in good faith commercialize Licensed Products in the
Territory in a manner to maximize commercial benefit of each Licensed Product
and consistent with the best interests of both Xoma and Pfizer.

                   SECTION 4.00 - PAYMENT PROCEDURES, REPORTS,
                            RECORDS, TAXES, AUDITING

     4.01 Sales among Pfizer, its Affiliates and sublicensees shall not be
subject to royalties under Section 3.00 hereof but in such cases royalties shall
be calculated upon Production Margin using Pfizer's or its Affiliates' or
sublicensees' Net
<PAGE>
                                      -10-

Sales to an independent third party. Notwithstanding to the contrary any other
provisions of this Agreement, Pfizer shall be responsible for payment of any
royalties accrued on sales of Licensed Products to such independent third party
through Pfizer's Affiliates or sublicensees.

     4.02 Pfizer shall pay to Xoma royalties on Production Margin for Net Sales
during each Payment Computation Period within sixty (60) days after the end of
each such Payment Computation Period, and each payment shall be accompanied by a
report identifying the Licensed Product, the Net Sales, Production Cost,
Production Margin and the royalties payable Xoma, as well as computation
thereof.

     4.03 Payments shall be made in United States Dollars and shall be remitted
to Xoma at its address first specified above. Royalties shall be paid by the
company actually making the sale giving rise to the payment obligation. Such
payments shall be subject to applicable law and regulations existing at the
place of remittance (namely, the location of the company actually making the
sale giving rise to the payment obligation). Net Sales shall first be determined
in the currency in which such Licensed Products were sold and shall then be
converted into the equivalent amount of United States Dollars at (a) the
official closing rate two business days prior to the date of payment hereunder,
as established by the central bank or exchange control authorities in each such
country; or (b) if no such official rate is available or if conversion pursuant
to such official rate cannot be effectuated by the company making the sale
giving rise to the payment obligation, then at the closing rate two business
days prior to the date of payment hereunder, established by a leading commercial
bank (selected by Pfizer) in the relevant country; or (c) if such official or
commercial bank rates are not available, or if conversion pursuant to the
provisions of clauses (a) or (b) hereof cannot be effectuated, then at the
closing rate two business days prior to the date of payment her under as
established by Chase Manhattan Bank, N.A., New York, New York.

     4.04 Any taxes required to be paid or withheld by Pfizer or its Affiliates
on account of amounts payable to Xoma under this Agreement shall be deducted
from the amounts due hereunder at the rates specified by applicable law. In
addition, Pfizer shall provide promptly to Xoma receipts from the government or
taxing authority evidencing payment of such taxes.

     4.05 Pfizer shall keep full and accurate books and records setting forth
gross sales, Net Sales, Product Cost, Production Margin and amounts payable to
Xoma hereunder. Xoma shall have

<PAGE>
                                      -11-

the right, at its own expense, during the term of this Agreement (but not later
than five (5) years following the rendering of any such reports, accountings and
payments) and for one (1) year thereafter, to have an independent public
accountant, reasonably acceptable to Pfizer, examine the relevant financial
books and records of account of Pfizer at normal business hours, upon reasonable
demand, to determine or verify such reports, accounting and payments. If errors
of five percent (5%) or more in Xoma's favor are discovered as a result of such
examination, Pfizer shall reimburse Xoma for the expense of such examination. As
a condition to such examination, the independent public accountant selected by
Xoma shall execute a written agreement, reasonably satisfactory in form and
substance to Pfizer, to maintain in confidence all information obtained during
the course of any such examination except for disclosure to Xoma as necessary
for the above purpose. The opinion of such independent public accountant
regarding such reports accounting and payments shall be binding on the parties
hereto.

     4.06 If at any time conditions or legal restrictions exist which conditions
or restrictions prevent the prompt remittance of the royalties due hereunder, or
if conversion into United States Dollars pursuant to the provisions of Section
4.03 hereof cannot be effectuated, the parties shall cooperate fully with each
other and make reasonable efforts to permit such remittance; if such efforts
shall be unsuccessful, Pfizer shall make such payments to Xoma within a
reasonable period of time.

          SECTION 5.00 - DISCLOSURE OF INFORMATION AND CONFIDENTIALITY

     5.01 Subject to the provisions of Section 5.4 of the R&D Agreement,
periodically during the term of this Agreement and at any time upon the
reasonable written request of Pfizer, Xoma shall disclose to Pfizer in
confidence, pursuant to Section 5.02 hereof, all Technical Information not
heretofore disclosed to Pfizer. Nothing however shall be deemed to require Xoma
to disclose to Pfizer any Technical Information which Xoma is, in good faith,
contractually prohibited from disclosing to third parties. All Technical
Information heretofore disclosed by Xoma to Pfizer shall be deemed to have been
disclosed pursuant to this Agreement and shall be subject to the provisions of
this Agreement, including but not limited to Section 5.02 hereof.

     5.02 Pfizer and its Affiliates shall keep confidential and not use, except
as provided herein, in the R&D Agreement, Supply Agreement (if in effect), or as
contemplated in the Security Agreement, all Technical Information supplied in
writing by Xoma during the term of this Agreement and for ten

<PAGE>
                                      -12-

(10) years after termination or expiration hereof; provided, however, that the
foregoing obligations of confidentiality and non-use shall not apply to the
extent that any Technical Information is demonstrated by written records to be
(a) already known to Pfizer or its Affiliates at the time of disclosure
hereunder or is hereafter developed by Pfizer or its Affiliates in the course of
work entirely independent of any disclosure hereunder; or (b) publicly known
prior to or after disclosure hereunder other than through acts or omissions of
Pfizer or its Affiliates; or (c) disclosed in good faith to Pfizer or its
Affiliates under a reasonable claim of right of which Pfizer is not aware of any
dispute; or (d) disclosed to third parties by Pfizer under a secrecy agreement
with essentially the same confidentiality provisions provided herein in
connection with the exercise of its rights under this Agreement, the R&D
Agreement, or the Supply Agreement (if in effect); or (e) disclosed by Pfizer in
connection with the exercise of its rights under the Security Agreement.
Notwithstanding to the contrary the foregoing, so long as Xoma shall be
supplying Pfizer with Products pursuant to the terms of the Supply Agreement,
prior to any disclosure of Technical Information regarding manufacturing or
production under circumstances described in the foregoing clause (d), Pfizer
shall notify Xoma of its proposed disclosure and shall not make any such
disclosure to any company as to which Xoma reasonably advises Pfizer, within 60
days of such notification, that there exists, in the reasonable business
judgment of Xoma, a substantial question as to whether such company can be
expected to comply with the provisions of such aforementioned secrecy agreement
relating to the confidential treatment of and restrictions as to the use of the
Technical Information. In addition, disclosure may be made (i) to governmental
agencies to the extent required or desirable to secure governmental approval for
marketing of any Licensed Product and (ii) to pre-clinical and clinical
investigators where necessary or desirable for their information to the extent
normal and usual in the custom of the trade and under a secrecy agreement with
essentially the same confidentiality provisions contained herein. Nothing herein
shall be construed to limit the right of clinical investigators from publishing
the results of their studies.

     5.03 During the term of this Agreement Xoma shall keep confidential and not
disclose to others or use for any purpose, other than as authorized herein, any
Technical Information or any know-how, data and information directed to the
Products disclosed by Pfizer hereunder; provided, however, the foregoing
obligations of confidentiality and non-use shall not apply to the extent that
such Technical Information, know-how, data and information is: (a) solely with
respect to know-how, data or

<PAGE>

                                      -13-

information disclosed to Xoma by Pfizer already known to Xoma at the time of
disclosure hereunder; or (b) publicly known prior to or after disclosure
hereunder other than through acts or omissions of Xoma or its employees; or (c)
disclosed in good faith to Xoma by a third party under a reasonable claim of
right; or (d) disclosed by Xoma to third parties under a secrecy agreement with
essentially the same confidentiality provisions provided herein with respect to
any Product in any Territory or country after such time as Pfizer has
surrendered the licenses granted hereunder pursuant to Section 2.00 hereof with
respect to such Territory or countries. In addition, disclosure may be made by
Xoma to third parties in order to fulfill Xoma's obligations under this
Agreement, the Supply Agreement or the R&D Agreement, provided that any such
disclosure shall be under a secrecy agreement with essentially the same
confidentiality provisions contained herein. In addition, disclosure may be made
by Xoma to governmental agencies to the extent required or desirable in exercise
of Xoma's rights hereunder, and to preclinical and clinical investigators where
necessary or desirable for their information to the extent normal and usual in
the custom of the trade and under a secrecy agreement with essentially the same
confidentiality provisions contained herein. Nothing herein shall be deemed to
limit the rights of clinical investigators from publishing the results of their
work. Nothing herein shall be deemed to limit Xoma's rights to use or license
any Technical Information or information, data or know-how generated by Xoma in
any manner not inconsistent with the licenses granted to Pfizer under this
Agreement.

     5.04 In connection with the furnishing to Pfizer of Technical Information
hereunder, Xoma agrees, at the request of Pfizer, to allow Pfizer personnel to
visit manufacturing and research facilities of Xoma and to consult with Xoma
personnel, at mutually agreeable times, to discuss and review Xoma's Technical
Information. In addition, Xoma agrees, at the request and expense of Pfizer, to
permit personnel of Xoma to visit Pfizer's manufacturing and research
facilities, at mutually agreeable times, to discuss and review Xoma's Technical
Information.

     5.05 Xoma agrees, upon the request of Pfizer, with respect to each Licensed
Product to give Pfizer copies of all submissions to or applications for
registration or approval by governmental health authorities (including, without
limitation all Product License Applications submitted to FDA). To the extent
legally possible, upon receipt by Xoma of any approvals by FDA of any Product
License Applications (including supplements thereto) covering any Licensed
Products, Xoma shall promptly assign to Pfizer such approved Product License

<PAGE>
                                      -14-

Applications; provided, however, Xoma shall have such rights of reference and
other rights as shall be necessary or appropriate for Xoma to perform (and/or
subcontract) its obligations to supply Licensed Products to Pfizer under the
terms of the Supply Agreement. In addition, Xoma shall assign to Pfizer, upon
request of Pfizer, or if not legally possible, grant to Pfizer rights of
reference under, all other governmental approvals, permits or registrations held
by Xoma or its Affiliates necessary to market any Licensed Products; provided,
however, the foregoing does have material adverse consequences to Xoma's other
operations and provided that reversion thereof to Xoma is reasonably feasible.
All of the foregoing will be at Pfizer's expense, and Pfizer shall be
responsible for requisite documentation.

                      SECTION 6.00 - REDUCTION OF ROYALTIES

     6.01 Royalties payable by Pfizer to Xoma under Section 3.00 hereof shall be
reduced or abated in their entirety, as the case may be, as follows:

          (a) In the event of any patent infringement, royalties shall be
     reduced as provided in Section 7.00 hereof.

          (b) If Pfizer within any country in the Territory is required by a
     final court order from which no appeal can be taken to obtain a license
     under any patent not licensed hereunder in order to make, use or sell
     Licensed Products and to pay a royalty under such license, and the
     infringement of such patent cannot reasonably by avoided by Pfizer,
     Pfizer's obligations to pay royalties under Section 3.01 hereof shall be
     reduced with respect to Net Sales in such country by the amount of the
     royalty payable by Pfizer under such additional license. Pfizer shall,
     however, make a good faith attempt to negotiate the royalty rate and
     calculation of royalties payable to such third parties with a view to
     minimizing the royalty to be deducted under this Section 6.01(b). In the
     event any such additional license shall be required for Territory A or any
     three Selected Countries in Territory B, Pfizer's obligation to pay minimum
     royalties under Section 3.03 hereof with respect to Net Sales in Territory
     A or Territory B, as the case may be, shall be reduced by the amount of
     royalties paid by Pfizer to such third party.

          (c) If a third party obtains, by order, decree or grant from a
     competent governmental authority in any country in the Territory, a
     compulsory license under Licensed Patents authorizing such third party to
     manufacture, use or sell any Licensed Product in such country, Xoma shall
     give prompt notice to Pfizer. During the effective period of such
     compulsory license, Pfizer's obligations to pay royalties under Section
     3.01 hereof with respect to sales in such country for such Licensed Product
     shall be reduced

<PAGE>
                                      -15-

     to a rate equivalent to the rate payable to Xoma by said third party, and
     Pfizer's obligations to pay minimum royalties under Section 3.03 hereof
     with respect to Net Sales in Territory A or Territory B, as the case may
     be, shall be terminated for so long as such compulsory license shall affect
     Territory A or any three Selected Countries in Territory B.

                             SECTION 7.00 - PATENTS

     7.01 Xoma shall take all reasonable steps and pay all necessary expenses to
prosecute the patent applications listed in Appendix I and shall take all
reasonable steps and pay all expenses necessary to maintain for the full life
thereof all Licensed Patents, unless Xoma, in consultation with Pfizer, shall in
good faith determine that it is not in the best interests of both parties for
Xoma to continue such prosecution, take such steps, or make such payments.
Pfizer shall have the right, upon consultation with Xoma, to file on behalf of
and as agent for Xoma all applications and take all actions necessary to obtain
the benefits under the Drug Price Competition and Patent Term Restoration Act of
1984 and any amendments thereof. Xoma agrees to sign such further authorizations
and instruments and take such further actions as may be requested by Pfizer to
implement the foregoing.

     7.02 If any claim relating to Licensed Patents becomes, within any country
in the Territory, the subject of a judgment, decree or decision of a court,
tribunal, or other authority of competent jurisdiction, which judgment, decree,
or decision is or becomes final (there being no further right of review) and
adjudicates the validity, enforceability, scope, or infringement of the same,
the construction of such claim in such judgment, decree or decision shall be
followed thereafter in such country in determining whether a product is licensed
hereunder, not only as to such claim but also as to all other claims to which
such construction reasonably applies. If at any time there are two or more
conflicting final judgments, decrees, or decisions with respect to the same
claim, the decision of the higher tribunal shall thereafter control, but if the
tribunal be of equal rank, then the final judgment, decree, or decision more
favorable to such claim shall control unless and until the majority of such
tribunals of equal rank adopt or follow a less favorable final judgment, decree,
or decision, in which event the latter shall control.

     7.03 If any patent infringement action shall be brought within any country
in the Territory against Pfizer or any Affiliate or sublicensee because of the
manufacture, use or sale of Licensed Products, Pfizer shall promptly notify Xoma
thereof. Pfizer and Xoma shall cooperate with each other in connection with any
such action. Pfizer shall continue to pay

<PAGE>
                                      -16-

royalties during the continuance of such infringement action and all appeals
thereof, provided that Pfizer or Xoma shall defend such action. If neither
Pfizer nor Xoma shall commence defense of such infringement action, upon request
by Pfizer to Xoma, then during the pendency of such infringement action,
Pfizer's obligations to pay royalties under Section 3.01 with respect to such
Licensed Product for sales in such country shall be suspended. In addition, if
such infringement action shall relate to Territory A or to any three Selected
Countries in Territory B, Pfizer's obligations to pay minimum royalties under
Section 3.03 for Net Sales in Territory A or Territory B, as the case may be,
shall be suspended during the continuance of such infringement action.

     7.04 If any third party shall, in the reasonable opinion of Pfizer,
infringe any of the Licensed Patents, Pfizer shall promptly notify Xoma. Pfizer,
its Affiliates or sublicensees shall have the right to bring suit and to take
action in its own name or in the name of Xoma where necessary. Xoma and Pfizer
shall, at the other's request, take all action necessary to assist in such suits
(including joining as a party), and each party shall bear its own expenses
relating thereto. Any monetary recovery in connection with such infringement
action shall be first applied to reimburse Xoma and Pfizer. Any balance shall be
shared equally by Pfizer and Xoma. If such recovery is less than the
out-of-pocket expenses, reimbursement shall first be on a pro-rata basis. During
the pendency of any such action, regardless of whether Pfizer or Xoma shall
prosecute such action, Pfizer shall continue to pay royalties due under Section
3.01, but Pfizer's obligations to pay minimum royalties under Section 3.03 for
Net Sales in Territory A or Territory B, as the case may be, shall be suspended
if such infringement shall be occurring in Territory A or any three Selected
Countries of Territory B.

                 SECTION 8.00 - UNIVERSITY OF CALIFORNIA LICENSE

     8.01 So as not to adversely affect Pfizer rights hereunder or under the R&D
Agreement, Xoma agrees during the term of this Agreement not to take any actions
to terminate or restrict its rights under the University of California License
as it relates to the Licensed Products, the Licensed Patents or Technical
Information and to discharge all of Xoma's material obligations and
responsibilities under the University of California License, including, without
limitation, making all required payments thereunder. In the event Xoma shall
receive any notice of default thereunder, Xoma shall promptly notify Pfizer. To
the extent, if any, Pfizer as Xoma's sublicensee shall have any obligations or
responsibilities to the University of California under the University of
California

<PAGE>
                                      -17-

License resulting from Xoma's sublicense to Pfizer hereunder, Pfizer shall
diligently discharge such obligations and responsibilities. In the event Pfizer
shall be required to pay any royalties under the University of California
License or otherwise shall be required to make any payments to the University of
California with respect to the manufacture, use or sale of Licensed Products
which are the subject of the University of California License, Pfizer shall be
permitted to deduct such royalties from any royalties or other amounts due Xoma
hereunder.

                       SECTION 9.00 - TERM AND TERMINATION

     9.01 This Agreement shall be effective as of the date first set forth above
and shall remain in effect for so long as Pfizer, its Affiliates or sublicensees
shall be obligated to make payments to Xoma under Section 3.00 hereof, unless
earlier terminated pursuant to this Section 9.00. Upon natural expiration of
this Agreement pursuant to this Section 9.01, the licenses granted to Pfizer
under Section 2.01 with respect to Technical Information shall be deemed to be
fully paid licenses. In addition, the provisions of Sections 5.02 and 10.00
hereof shall survive the expiration or any termination of this Agreement.

     9.02 At any time, upon sixty (60) days' prior notice to Xoma, Pfizer shall
have the right, without cause at Pfizer's sole discretion, to terminate in full
this Agreement, whereupon this Agreement together with the R&D Agreement and
Supply Agreement (if still in effect) shall terminate sixty (60) days after the
date of such notice.

     9.03 At any time Pfizer shall be permitted to terminate its rights and
licenses granted hereunder with respect to any Product as provided in Sections
6.1 and 10.2(a) of the R&D Agreement. In the event of such termination, all
licenses of Pfizer hereunder with respect to such Product shall terminate, and
Pfizer, at its expense, shall return to Xoma all Technical Information regarding
such Product (including all Product License Applications and all other rights
regarding such Product assigned to Pfizer hereunder.)

     9.04 If either Pfizer or Xoma materially breaches or defaults in the
performance or observance of any of the provisions of this Agreement, and such
breach or default is not cured within ninety (90) days or, in the case of
failure to pay an amounts due hereunder, sixty (60) days after the giving of
notice by the other party specifying such breach or default, the other party
shall have the right to terminate this Agreement in full upon a further thirty
(30) days' notice.

     9.05 Upon termination under Sections 9.02 or 9.04 hereof, or Section
10.3(b) of the R&D Agreement, or termination in full

 <PAGE>
                                      -18-

under Section 6.1 of the R&D Agreement, or termination by Pfizer under Section
10.3(c) of the R&D Agreement, and except as otherwise provided to the contrary
in the Security Agreement, all licenses of Pfizer hereunder shall terminate and
all obligations and restrictions upon Xoma shall terminate, and Pfizer shall, at
its expense, return to Xoma all Technical Information (including all Product
License Applications and all other rights assigned to Pfizer hereunder) and use
reasonable efforts to return to Xoma all copies thereof provided, however, none
of the provisions of this Section 9.05 shall apply in the event Pfizer shall
terminate this Agreement under Section 9.04 hereof for Xoma's breach of its
obligations under Section 2.01 hereof or if Pfizer shall terminate the R&D
Agreement under Section 10.3(c) thereof for Xoma's breach of its obligations
under Sections 4.1 or 4.2 of the R&D Agreement, and in each case the parties
shall have whatever rights and remedies are provided at law or in equity.

     9.06 Termination of this Agreement for any reason shall be without
prejudice to:

     (a) The rights and obligations of the parties provided in Sections 5.02 and
10.00 hereof.

     (b) Xoma's right to receive all payments accrued under Section 3.00 hereof
prior to the effective date of such termination; and

     (c) Any other remedies which either party may otherwise have.

                         SECTION 10.00 - INDEMNIFICATION

     10.01 Except as otherwise provided in the Supply Agreement (if then in
effect), Xoma shall indemnify Pfizer against any and all liability, damages,
loss, cost and expenses, including reasonable attorneys' fees made against or
sustained by Pfizer or any of its Affiliates arising from the death of, or
bodily injury to, any person on account of the ingestion or use of any Licensed
Product (collectively "Pfizer Losses") to the extent such Pfizer Losses are
finally determined by a court of competent jurisdiction or by specific reference
in a settlement of litigation consented to by Xoma pursuant to Section 10.04 to
have been caused by Xoma's gross negligence or willful misconduct.

     10.02 Except as otherwise provided in the Supply Agreement (if then in
effect), Pfizer shall indemnify Xoma against any and all liability, damages,
loss, cost and expenses, including reasonable attorneys' fees made against or
sustained by Xoma or any of its Affiliates arising from the death of, or bodily
injury to, any person on account of the ingestion or use of any Licensed Product
(collectively "Xoma Losses") to the extent <PAGE>
                                      -19-

such Xoma Losses are finally determined by a court of competent jurisdiction or
by specific reference in a settlement of litigation consented to by Pfizer
pursuant to Section 10.4 to have been caused by Pfizer's gross negligence or
willful misconduct.

     10.03 The indemnities of Sections 10.01 and 10.02 shall not apply (i) if
the indemnified party fails to give the indemnifying party prompt notice of any
claim it receives and such failure materially prejudices the indemnifying party,
or (ii) unless the indemnifying party is given the opportunity to approve any
settlement, which approval shall not be unreasonably withheld. Furthermore, the
indemnifying party shall not be liable for attorneys' fees or expenses of
litigation of the indemnified party unless the indemnified party gives the
indemnifying party the opportunity to assume control of the defense or
settlement. In addition, if the indemnifying party assumes such control, it
shall only be responsible for the legal fees and litigation expenses of the
attorneys it designates to assume control of the litigation. In no event shall
the indemnifying party assume control of the defense of the indemnified party
without the consent of the indemnified party (which consent shall be given or
not at its sole discretion).

     10.04 In no event shall the indemnified party be entitled to settle any of
the above-mentioned claims without the consent of the indemnifying party, which
consent shall not be unreasonably withheld.

     10.05 To the extent the foregoing indemnities shall not be applicable, the
parties shall have such rights and remedies as provided by law.

                          SECTION 11.00 - MISCELLANEOUS

     11.01 Force Majeure. No party shall be liable for failure of or delay in
performing obligations set forth in this Agreement, and no party shall be deemed
in breach of its obligations, if such failure or delay is due to natural
disasters or any causes reasonably beyond the control of such party.

     11.02 Assignability. The Agreement may not be assigned by either party
without the prior consent of the other party; provided, however, (a) either
party may assign this Agreement to any entity which acquires substantially all
of its assets and business, and (b) Pfizer may assign this Agreement, in whole
or in part, to any Affiliate of Pfizer.

     11.03 Pfizer Status. For the purpose of carrying out this Agreement Pfizer
shall act as an independent contractor and not as partner, joint venturer, or
agent and shall not bind nor attempt to bind Xoma to any contract.

<PAGE>
                                      -20-

     11.04 Notices. Any notice, consent or approval required under this
Agreement shall be in writing sent by registered or certified airmail, postage
prepaid, or by telex or cable (confirmed by such registered or certified mail)
and addressed as follows:

If to Pfizer:                               If to Xoma:

Pfizer Inc.                                 Xoma Corporation
235 East 42nd Street                        2910 Seventh Street
New York, New York  10017                   Berkeley, California  94710
Telex:  420440                              Telex:  856-697
Attention:  General Counsel                 Attention:  Chairman

All notices shall be deemed to be effective on the date of mailing. In case any
party changes its address at which notice is to be received, written notice of
such change shall be given without delay to the other party.

     11.05 Entire Agreement. This Agreement together with the R&D Agreement, the
Supply Agreement and the Security Agreement and any other agreements referred to
in any of the foregoing set forth the entire agreement and understanding among
the parties hereto as to the subject matter hereof and has priority over all
documents, verbal consents or understandings made between Pfizer and Xoma before
the conclusion of this Agreement with respect to the subject matter hereof; none
of the terms of this Agreement shall be amended or modified except in writing
signed by the parties hereto.

     11.06 Waivers. A waiver by any party of any term or condition of this
Agreement in any one instance shall not be deemed or construed to be a waiver of
such term or condition for any similar instance in the future or of any
subsequent breach hereof.

     11.07 Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California without regard to the
conflicts of laws provisions thereof. The exclusive jurisdiction and venue of
any action with respect to this Agreement shall be the Superior Court of
California for the County of Alameda or the United States District Court for the
Northern District of California and each of the parties hereto submits itself to
the exclusive jurisdiction and venue of such courts for the purpose of any such
action. Service of process in any such action may be effected in the manner
provided in Section 11.04 for delivery of notices. The prevailing party in any
legal action to enforce or interpret this Agreement shall be entitled to costs
and attorney's fees.

<PAGE>
                                      -21-

     11.08 Remedies. The rights and remedies of a party set forth herein with
respect to failure of the other to comply with the terms of this Agreement
(including, without limitation, rights of full or partial termination of this
Agreement) are not exclusive, the exercise thereof shall not constitute an
election of remedies and the aggrieved party shall in all events be entitled to
seek whatever additional remedies may be available in law or in equity.

     11.09 Security Agreement. Pfizer's rights under this Agreement are secured
pursuant to the terms of a Security Agreement, dated the date hereof, between
Pfizer and Xoma, and reference is made to said agreement for a description of
the terms thereof. Notwithstanding to the contrary any provision of this License
Agreement, nothing herein shall be deemed to restrict, limit, modify or alter
any of Pfizer's rights under the Security Agreement or derived upon or resulting
from the exercise of any rights or interests thereunder.

     11.10 Other Products. During the term of this Agreement, Pfizer shall not
sell in any Territory or country in which Pfizer has licenses hereunder any
monoclonal-based antibody product for the treatment of Septic Shock other than
the Licensed Products, unless such other antibody product shall be substantially
different from and materially clinically superior to (for a clinically relevant
indication) any Licensed Product.

     11.11 Headings. Headings in this Agreement are included herein for ease of
reference only and shall have no legal effect.

     IN WITNESS WHEREOF, the parties hereto have caused this License Agreement
to be executed as of the date first written above by their duly authorized
officers.


                             XOMA CORPORATION

                             By /s/Steven C. Mendell
                                   Chairman/ CEO

                             PFIZER INC.

                             By /s/William C. Steere
                                  Vice President

<PAGE>
                                   APPENDIX I
                                LICENSED PATENTS
<PAGE>
                                                     APPENDIX I
                                                  LICENSED PATENTS
I                              II                        III

US 06/855,878 (2)              US 06/781,242 (1)       US 06/855,878 (2)

                                      (Plus
                                     foreign
                                     filings
                                     listed
                                      under
                                                         Col
                                                         I)
AUSTRALIA 63236/86             US 06/855,878 (2)       US 07/036,766 (3)
CANADA 519,066                 U.S. 07/036,766 (3)
EUROPE 86306420.0
  (10 EPO Countries)
IRELAND 2546/86
ISRAEL 79719
JAPAN 229481/86
KOREA 8128/86
NEW ZEALAND 217283
PHILLIPINES 34297
SOUTH AFRICA 86/7342
SPAIN 8602198
U.S. 07/036,766 (3)


- ----------

(1) Filing Date 9/27/84 (2) Filing Date 4/24/86 (3) Filing Date 4/10/87


<PAGE>


                                SUPPLY AGREEMENT

     This Agreement ("Agreement"), dated as of June 9, 1987, by and between XOMA
CORPORATION ("XOMA"), a Delaware corporation, and PFIZER INC. ("Pfizer"), a
Delaware corporation.

                                   WITNESSETH:

     WHEREAS, XOMA is engaged in research and clinical studies on monoclonal
antibody-based biological drug products; and

     WHEREAS, Pfizer wishes to purchase certain of such products from XOMA in
bulk purified form, and XOMA is willing to supply Pfizer with such products.

     NOW, THEREFORE, in consideration of the premises and the mutual promises
and covenants set forth below, XOMA and Pfizer mutually agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

     1.1 "Affiliate" shall mean (a) any company owned or controlled to the
extent of at least fifty percent (50%) of its issued and voting capital by a
party to this Agreement and any other company so owned or controlled (directly
or indirectly) by any such company or the owner of any such company, or (b) any
partnership, joint venture or other entity directly or indirectly controlled by,
controlling, or under common control of, to the extent of fifty percent (50%) or
more of voting power (or otherwise having power to control its general
activities), a party to this Agreement, but in each case only for so long as
such ownership or control shall continue.

     1.2 "Agreement" shall mean this Supply Agreement, as amended from time to
time.

     1.3 "Delivery Date" shall have the meaning set forth n Section 2.2. hereof.

     1.4 "FDA" means the United States food and Drug Administration.

     1.5 "First Commercial Sale" shall mean, as to each Product, the first
commercial sale by Pfizer, its Affiliates or sublicensees of such Product
following Product Approval.

<PAGE>
                                      -2-

     1.6 "Initial Term" shall have the meaning set forth in Section 5.1 hereof.

     1.7 "License Agreement" means the agreement so named dated the date hereof
between Pfizer and XOMA.

     1.8 "Manufacturing Cost" means XOMA'S manufacturing cost for each product
as determined pursuant to Exhibit I attached hereto and made a part hereof.

     1.9 "Product" shall mean each subject product (as defined under the R.D&O
Agreement unless terminated thereunder) supplied hereunder by Xoma in purified
bulk form and meeting the specifications set forth in Exhibit II, attached
hereto and made a part hereof, as such Exhibit is amended by the parties from
time to time.

     1.10 "Product Approval" means final FDA approval to market commercially in
the U.S.A. the specified Product for use in humans.

     1.11 "R,D&O Agreement" means the Research, Development and Option Agreement
dated the day hereof between Pfizer and XOMA.

                                   ARTICLE II

                          SALE AND PURCHASE OF PRODUCTS

     2.1 Sale and Purchase. XOMA, within the limitations contained in this
Article, agrees to sell to Pfizer such quantities of Product as Pfizer may
require for sale pursuant to the License Agreement. Subject to the provisions of
Sections 4.1 and 5.1 hereof, so long as this Agreement shall remain in effect,
XOMA agrees to sell, and Pfizer agrees, for 100% of Pfizer's, its Affiliates'
and sublicensees' requirement of Product. It is understood that Xoma shall have
the right in connection with supply hereunder to contract with respect to
manufacture of Product with such third parties as Xoma deems advisable,
provided, however, Xoma shall remain fully responsible hereunder.

     2.2 Quantity; Forecasts.

     (a) With respect to each Project, Pfizer shall deliver to XOMA (i) at least
four (4) full calendar quarters prior to the calendar quarter in which the First
Commercial Sale of such Product is projected to occur, a forecast of Pfizer's
quantity requirements for such Product for the calendar quarter in which the
First Commercial Sale of such Product is projected to occur

<PAGE>
                                      -3-

and (ii) at least one (1) full calendar quarter prior to the calendar quarter in
which the First Commercial Sale of such Product ("Delivery Date") for such
calendar quarter and a forecast of its quantity requirements for such Product
for the three (3) following calendar quarters. Thereafter, Pfizer shall deliver
to XOMA at or prior to the end of each calendar quarter, Pfizer's firm order and
Delivery Date for such Product for the second calendar quarter following such
calendar quarter and a forecast of its quantity requirements for such Product
for the three (3) following calendar quarters.

     For purposes of illustration only, on or before September 30, 1987, Pfizer
must give to XOMA its firm order for delivery of Product in the first calendar
quarter of 1988 and a forecast of its requirements for the second, third and
fourth quarters of 1988. On or before December 31, 1987, Pfizer must give XOMA
its firm order for delivery of Product in the second quarter of 1988, updated
forecasts of its requirements for the third and fourth quarter of 1988 and a
forecast of its requirements for the first quarter of 1989.

     (b) For each quarterly forecast of Product, the amount of Product
forecasted for delivery in the first of the three calendar quarters forecasted
shall be not less than fifty percent (50%) or more than one hundred fifty
percent (150%) of the most recent previous forecast for such quarter.

     (c) The total amount of each Product ordered by Pfizer for delivery in any
one calendar quarter may not be less than seventy-five percent (75%) of Pfizer's
most recent forecast of its requirements for such Product for such quarter. In
addition, XOMA will not be obligated to supply more than one hundred twenty-five
percent (125%) of Pfizer's most recent forecast of its requirements for such
product for such quarter. If a Pfizer product requirement for any quarter
exceeds 125% of Pfizer's most recent forecast of its requirements for such
Product for such calendar quarter, XOMA and Pfizer will discuss in good faith
the additional amount which XOMA will be able to supply consistent with its
other obligations and Pfizer will adjust its order accordingly (however,
Pfizer's orders will have first priority on equipment funded under the Credit
Agreement between the parties of even date herewith). Pfizer shall indemnify
XOMA and reimburse it promptly upon request for all reasonable out of pocket
costs and expenses, including the cost of carrying increased inventory, to the
extent caused by any deviation in order quantities from the limits imposed by
the preceding sentence, and XOMA will act reasonably to mitigate any such costs
and expenses.

<PAGE>
                                      -4-

     2.3 Delivery.

     (a) XOMA shall, subject to the terms of this Agreement, deliver to Pfizer
all Product ordered by Pfizer. All Products delivered to Pfizer shall be F.O.B.
XOMA's plant or other place of shipment. XOMA shall use its reasonable best
efforts to assist Pfizer in arranging any desired insurance (in amounts that
Pfizer shall determine) and transportation, via air freight unless otherwise
specified in writing, to any destinations specified in writing from time to time
by Pfizer. All customs, duties, costs, taxes, insurance premiums, and other
expenses relating to such transportation and delivery, shall be at Pfizer's
expense.

     (b) XOMA will package the Products in accordance with the specifications
set forth in Exhibit II hereto.

     2.4 Rejection of Product in Case of Nonconformity.

     (a) Pfizer may reject any shipment of Product which is (i) not conforming
with the specifications contained in Exhibit II or (ii) adulterated or
misbranded within the meaning of the Federal, Food, Drug and Cosmetic Act (the
"Act"). In order to reject a shipment, Pfizer must (i) give notice to XOMA of
Pfizer's intent to reject the shipment within thirty (30) days of receipt
together with an indication of the reasons for such possible rejection, and (ii)
as promptly as reasonably possible thereafter, provide XOMA with notice of final
rejection and the full basis therefor. After notice of intention to reject is
given, Pfizer shall be deemed to have accepted such delivery of Product,
provided, however, in the case of products having latent defects which upon
diligent examination by Pfizer upon receipt could not have been discovered,
Pfizer must give notice of Pfizer's intent to reject within thirty (30) days
after discovery of such defects.

     In any event, Pfizer shall pay for the shipment as otherwise provided
herein and shall be entitled to a refund of the purchase price (together with
insurance and freight charges) of rejected Products at the time they are
ultimately rejected, provided that if XOMA disputes the rejection, refund shall
be made at the time the dispute is finally resolved. XOMA shall notify Pfizer as
promptly as reasonably possible whether it accepts Pfizer's basis for any
rejection.

     (b) Whether or not XOMA accepts Pfizer's basis for rejection, promptly on
receipt of a notice of rejection, XOMA

<PAGE>
                                      -5-

shall use its reasonable efforts, at Pfizer's request, to provide replacement
Product which shall be purchased by Pfizer as provided hereunder.

     (c) Unless XOMA requests the return to it of a rejected batch within sixty
(60) days of receipt of Pfizer's notice of rejection, Pfizer shall destroy such
batch promptly and provide XOMA with certification of such destruction. Pfizer
shall, upon receipt of XOMA's request for return, promptly dispatch said batch
to XOMA, at XOMA's cost.

                                   ARTICLE III

                               PRICE AND PAYMENTS

     3.1 Price. Pfizer shall pay to XOMA for Product purchased hereunder an
amount equal to [*] or such amount as determined under Section 4.1(a) hereof.

     3.2 Method of Payment. All payments due hereunder to XOMA shall be paid to
XOMA in United States dollars not later than thirty (30) days following the date
of the applicable invoice.

     3.3 Examination of Books. Pfizer shall have the right, at its own expense,
for any period during which Product is purchased by Pfizer hereunder and for one
(1) year thereafter, to have an independent public accountant, reasonably
acceptable to XOMA, examine the relevant financial books and records of account
of XOMA at normal business hours, upon reasonable demand, to determine or verify
the appropriate manufacturing Cost of Product purchased hereunder. If errors of
five percent (5%) or more in Pfizer's favor are discovered as a result of such
examination, XOMA shall reimburse Pfizer for the expense of such examination. As
a condition to such examination, the independent public accountant selected by
Pfizer shall execute a written agreement, reasonably satisfactory in form and
substance to XOMA, to maintain in confidence all information obtained during the
course of any such examination except for disclosure to Pfizer as necessary for
the above purpose. The opinion of such independent public accountant shall be
binding on the parties hereto with respect to Manufacturing Cost hereunder.

                                   ARTICLE IV

                                SUPPLY OBLIGATION

     4.1 Termination of Supply Obligations, Breach of Delivery Obligation. In
addition to any Termination of this Agreement

<PAGE>
                                      -6-

under Article V hereof, this Agreement shall terminate as follows:

     (a) If at any time after the Initial Term Pfizer notifies XOMA that Pfizer
has received a good faith firm quote from a reputable third party supplier of
recognized standing (other than an Affiliate) to supply Pfizer for a period of
at least two years with all Pfizer's requirements of any Product at a price
which is less than 75% of XOMA's then current transfer price to Pfizer of such
product, XOMA shall have sixty (60) days after receipt of such notice to notify
Pfizer that XOMA intends or does not intend to reduce its then applicable
transfer price of such Product to a price no greater than 125% of the third
party quoted price effective upon the expiration of such 60-day period. If XOMA
fails to give such notice or notifies Pfizer that it does not intend to so
reduce its then applicable transfer price of such Product, Pfizer may, upon
thirty (30) day's prior notice to XOMA, elect to terminate its obligations
hereunder to purchase, and XOMA's obligations to supply, such product.
Notwithstanding the foregoing, Pfizer shall have not rights under this Section
4.1(a) if the third party quote is given in connection with or in anticipation
of some other relationship with Pfizer.

     (b) If XOMA materially fails to deliver the amount of any Product ordered
by Pfizer as required hereunder for any reason, including force majeure, or XOMA
fails to deliver Product conforming to the warranties set forth in Section 6.1
hereof, in each case for ninety (90) or more consecutive days, then Pfizer may
upon twenty (20) days prior notice to XOMA elect to terminate Pfizer's
obligations to purchase, and XOMA's obligations to supply, such Product
hereunder. Except as otherwise expressly provided in Section 6.2 hereof, and
except in the case where XOMA has generally not been attempting in good faith to
meet its supply obligations, the foregoing shall be Pfizer's sole remedy for
breach of warranty or for failure of XOMA to supply products hereunder.

                                    ARTICLE V

              TERMINATION, RIGHTS AND OBLIGATIONS UPON TERMINATION

     5.1 Term. Unless termination for any particular Product pursuant to
Sections 4.1(a) or 4.1(b) hereof or by either party pursuant to the other
provisions of this Article v, this Agreement shall continue in effect for a
period of three (3) years from the date of First Commercial Sale of the first
Product supplied hereunder (the `Initial Term"), and shall thereafter remain in
effect until terminated by XOMA upon at least one (1) year prior notice to
Pfizer (which notice may be given any time after the second year of the Initial
Term). In addition, Pfizer shall have the right at any time after the Initial
Term to terminate this Agreement upon three years' prior notice (given after the
Initial

<PAGE>
                                      -7-

Term)to XOMA, provided however, Pfizer shall be required to purchase from Xoma
100% of its requirements and those of its Affiliates and sublicensees in the
first year after said notice, 50% of such requirements in the second such year
and 25% of such requirement in the third such year provided further that XOMA
shall have the right, by notice given to Pfizer not more than 60 days after the
date of any Pfizer notice of termination under this Section 5.1, to decline to
supply any Product in the second and third year after the date of Pfizer's
termination notice.

     5.2 Termination by Mutual Agreement. This Agreement may be terminated upon
mutual written agreement between the parties.

     5.3 Termination by Default. If either party materially defaults in the
performance of any materials agreement, condition or covenant of this Agreement,
the R,D&O Agreement or the License Agreement, and such default or noncompliance
shall not have been remedied, or steps initiated to remedy the same to the other
party's reasonable satisfaction, within ninety (90) days after receipt by the
defaulting party of a notice thereof from the other party, the party not in
default may terminate this Agreement.

     5.4 Termination of License Rights. In the event any Product supplied
hereunder shall no longer be a Licensed Product under the License Agreement or
Pfizer's license with respect thereto under the License Agreement is no longer
in effect, then Pfizer's obligations to purchase and XOMA's obligation to supply
such Product hereunder shall terminate.

     5.5 Rights and Obligations on Term, Termination or Suspension. Unless
expressly provided to the contrary, the following provisions shall survive the
termination of this Agreement: Article III, the last sentence of Section 4.1(b),
this Section 5.5 and Article VI. Any rights of XOMA to payments accrued through
termination as well as obligations of the parties under firm orders for purchase
and delivery of Products at the time of such termination shall remain in effect.

                                   ARTICLE VI

                          WARRANTY AND INDEMNIFICATION

     6.1 Warranties. XOMA warrants that the Products, when shipped to Pfizer by
XOMA, (i) will conform in all respects to the specifications set forth on
Exhibit II, as then in effect, and (ii) will not be adulterated or misbranded
within the meaning of the Act. PFIZER'S SOLE AND EXCLUSIVE REMEDY FOR ANY BREACH
OF THE FOREGOING WARRANTIES SHALL BE ITS RIGHTS UNDER SECTIONS 2.4, 4.1(B) and
6.2 HEREOF. EXCEPT FOR THE FOREGOING WARRANTIES, XOMA DOES NOT WARRANT THE
MERCHANTABILITY OR

<PAGE>
                                      -8-

FITNESS FOR A PARTICULAR PURPOSE OF THE PRODUCTS OR THE PERFORMANCE THEREOF,
DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, WITH RESPECT TO PRODUCTS,
SPECIFICATION, SUPPORT, SERVICE OR ANYTHING ELSE AND DOES NOT MAKE ANY WARRANTY
TO PFIZER'S CUSTOMERS OR AGENTS. XOMA HAS NOT AUTHORIZED ANYONE TO MAKE ANY
REPRESENTATION OR WARRANTY OTHER THAN AS PROVIDED ABOVE. THE FOREGOING
LIMITATIONS OF WARRANTIES SHALL NOT IN ANY WAY LIMIT PFIZER'S RIGHTS UNDER
SECTION 6.2 HEREOF.

     6.2 XOMA Indemnification.

     (a) XOMA shall indemnify Pfizer against any and all liability, damages,
loss, cost and expenses, including reasonable attorneys' fees made against or
sustained by Pfizer or any of its Affiliates arising from the death of, or
bodily injury to, any person on account of the ingestion or use of any Product,
and any reasonable out-of-pocket costs to Pfizer and its Affiliates of the
recall of any Product (collectively "Pfizer Losses") to the extent (i) such
Pfizer Losses are finally determined by a court of competent jurisdiction or by
specific reference in a settlement of litigation consented to by XOMA pursuant
to Section 6.5 to have been caused by XOMA's failure to deliver such Product in
accordance with XOMA's warranties as provided in this Agreement or (ii) such
Pfizer Losses are finally determined by a court of competent jurisdiction or by
specific reference in a settlement of litigation consented to by XOMA pursuant
to Section 6.5 to have been caused by XOMA's gross negligence or willful
misconduct.

     (b) In addition to indemnification pursuant to Section 6.2(a)hereof, and
except in cases where Xoma is entitled to indemnification under 6.3(a0 hereof,
XOMA shall further indemnify Pfizer for any and all Pfizer Losses arising from
the death of, or bodily injury to, any person on account of the ingestion or use
of any Product to the extent such Pfizer Losses are finally determined by a
court of competent jurisdiction or by XOMA pursuant to Section 6.5 to have been
caused other than by Pfizer's gross negligence or willful misconduct, and then
(i) with respect to each such incident to the extent of the first $1,000,00 of
XOMA's insurance coverage for such Losses, and (ii) to the extent any Pfizer
Losses exceed Pfizer's recovery pursuant to such insurance, XOMA's
indemnification shall be to the extent of the lesser of (a) such excess Pfizer
Loses or (b) one-half of the aggregate of such excess Pfizer Losses and related
Xoma Losses referred to in Section 6.3(b) hereof. XOMA agrees to use its best
efforts to procure and, at all times during the term of this Agreement and for a
period of three (3) years after the termination hereof, to maintain in full
force and effect liability insurance coverage of at least $1,000,000 per
occurrence (with a deductible of no more than $250,000 aggregate per year

<PAGE> 

                                      -9-

with Pfizer as a named insured party as provided herein). Such insurance

shall cover any and all Pfizer Losses (as provided herein for which
indemnification is provided by this Section 6.2(b)) and Xoma's contractual
liability hereunder to indemnify Pfizer as provided in this Section 6.2(b), in
each case to the extent such insurance coverage in such amount is obtainable at
premiums which are reasonable in the reasonable good faith judgment of XOMA.
Xoma, upon request of Pfizer, will supply Pfizer with appropriate certificates
of insurance evidencing the foregoing insurance.

     6.3 Pfizer Indemnification.

     (a) Pfizer shall indemnify XOMA against any and all liability, damages,
loss, cost and expenses, including reasonable attorneys' fees made against or
sustained by XOMA or any of its Affiliates arising from the death of, or bodily
injury to, any person on account of the ingestion or use of any Product
(collectively "XOMA Losses") to the extent such XOMA Losses are finally
determined by a court of competent jurisdiction or by specific reference in a
settlement of litigation consented to by Pfizer pursuant to Section 6.5 to have
been caused by Pfizer's gross negligence or willful misconduct.

     (b) In addition to indemnification pursuant to Section 6.3(a) hereof, and
except in cases where Pfizer is entitled to indemnification under Section 6.2(a)
hereof, Pfizer shall further indemnify XOMA for any and all XOMA Losses arising
from the death of, or bodily injury to, any person on account of the ingestion
or use of any Product to the extent such XOMA Losses are finally determined by a
court of competent jurisdiction or by specific reference in a settlement of
litigation consented to by Pfizer pursuant to Section 6.5 to have been caused
other than by XOMA's gross negligence or willful misconduct, and then with
respect to each incident to the extent of the lesser of (a) such XOMA Losses or
(b) one-half of the aggregate of such XOMA Losses and the related Pfizer Loses
referred to in Section 6.2(b) hereof which are in excess of the recovery by
Pfizer under the XOMA insurance policy pursuant to Section 6.2(b) hereof.

     6.4 Limitations to Indemnity. The indemnities of Sections 6.2 and 6.3 shall
not apply (i) if the indemnified party fails to give the indemnifying party
prompt notice of any claim it receives and such failure materially prejudices
the indemnifying party, or (ii) unless the indemnifying party is given the
opportunity to approve any settlement, which approval shall not be unreasonably
withheld. Furthermore, the indemnifying party shall not be liable for attorneys'
fees or expenses of litigation of the indemnified party unless the indemnified
party gives the indemnifying party the opportunity to assume control of the
defense or settlement. In addition, if the indemnifying party assumes such
control, it shall only be responsible for the legal fees and litigation expenses
of the attorneys it designates to assume control of the litigation. In no event
shall the indemnifying party assume control of the defense of the indemnified
party without the consent of the indemnified party (which consent shall be given
or not at its sole discretion).

<PAGE>

                                      -10-

     6.5 Settlement. In no event shall the indemnified party be entitled to
settle any of the above-mentioned claims without the consent of the indemnifying
party, which consent shall not be unreasonably withheld.

                                   ARTICLE VII

                                  MISCELLANEOUS

     7.1 Entire Agreement. This Agreement contains the entire agreement of the
parties regarding the subject matter hereof and, together with the License
Agreement, R,D&O Agreement and all other agreements referred to therein,
supersede all prior agreements, understandings and negotiations regarding the
same. This Agreement may not be changed, modified, amended or supplemented
except by a written instrument signed by both parties.

     7.2 Assignability. This Agreement may not be assigned by either party
without the prior consent of the other party; provided, however, (a) either
party may assign this Agreement to any entity which acquires substantially all
of its assets and business, and (b) Pfizer may assign this Agreement, in whole
or in part, to any Affiliate of Pfizer.

     7.3 Severability. If any part of this Agreement shall be held
unenforceable, the remainder of the Agreement shall nevertheless remain in full
force and effect.

     7.4 Further Assurances. Each party hereto agrees to execute, acknowledge
and deliver such further instruments, and to do all such other acts, as may be
necessary or appropriate in order to carry out the purposes and intent of this
Agreement.

     7.5 Use of Party's Name. No right, express or implied, is granted by this
Agreement to either party to use in any manner the name of the other or any
other trade name or trademark of the other in connection with the performance of
this Agreement.

     7.6 Notice and Reports. All notices, consents or approvals required by this
Agreement shall be in writing sent by certified or registered air mail, postage
prepaid or by telex or cable (confirmed by such certified or registered mail) to
the parties at the following addresses or such other addresses as may be
designated in writing by the respective parties:

<PAGE>
                                      -11-

                  To XOMA:          XOMA Corporation
                                    2910 Seventh Street
                                    Berkeley, California 94710
                                    Attention:  Chairman
                                    Telex: 856-697

                  To Pfizer:        Pfizer Inc.
                                    235 East 42nd Street
                                    New York, New York 10017
                                    Attention: General Counsel
                                    Telex: 420440

Notices shall be deemed effective on the date of the mailing.

     7.7 Relationships of the Parties. Both parties are independent contractors
under this Agreement. Nothing contained in this Agreement is intended nor is to
be construed so as to constitute XOMA and Pfizer as partners or joint venturers
with respect to this Agreement. Neither party hereto shall have any express or
implied right or authority to assume or create any obligations on behalf of or
in the name of the other party or to bind the other party to any contract,
agreement or undertaking with any third party.

     7.8 Waiver. The waiver by either party of a breach of any provisions
contained herein shall be in writing and shall in no way be construed as a
waiver of any succeeding breach of such provision of the waiver of the provision
itself.

     7.9 Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California without regard to the
conflicts of laws provisions thereof. The exclusive jurisdiction and venue of
any action with respect to this Agreement shall be the Superior Court of
California for the County of Alameda or the United States District Court for the
Northern District of California and each of the parties hereto submits itself to
the exclusive jurisdiction and venue of such courts for the purpose of nay such
action. Service or process in any such action may be effected in the manner
provided in Section 7.6 for delivery of notices. The prevailing party in any
legal action to enforce or interpret this Agreement shall be entitled to
reasonable costs and attorney's fees.

     7.10 Captions. Paragraph captions are inserted for convenience only and in
no way are3 construed to define, limit or affect the construction or
interpretation hereof.

     7.11 Force Majeure. A party shall not be liable for nonperformance or delay
in performance caused by any event

<PAGE>
                                      -12-

reasonably beyond the control of such party including, but not limited to wars,
hostilities, revolutions, riots, civil commotion, national emergency strikes,
lockouts, unavailability of supplies, epidemics, fire, flood, earthquake, force
of nature, explosion, embargo, or any other Act of God, or any law,
proclamation, regulation, ordinance, or other act or order of any court,
government or governmental agency.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement to be
effective as of the date first written above.

XOMA Corporation                    PFIZER INC.


By:  /s/Steven C. Mendell           By:  /s/William C. Steere
Title  Chairman/CEO                      Title  Vice President


<PAGE>


                                    EXHIBIT I
                               MANUFACTURING COST
<PAGE>
                                    EXHIBIT I
                               MANUFACTURING COSTS

Xoma will provide the Product to Pfizer at its direct cost of production as
evidenced by written records plus a reasonable allowance for manufacturing
overhead based on utilization of the facility for the Product as a percentage of
capacity as follows:

Direct Costs of Production

     Labor - Actual cost of labor incurred for production of the Product.

     Materials - Actual cost of materials consumed in the manufacture of the
     Product

     Quality Control - Actual cost of labor hours and supplies used in the
     testing and inspection of the Product.

     Manufacturing Overhead

     The cost of required manufacturing support services and supplies. Product
     cost will include the percentages of these costs that the product
     represents as a percentage of total production capacity for the year.
     Pfizer and Xoma will use their best efforts to develop these percentages at
     the time the PLA is filed with the FDA and annually thereafter. If the
     parties are unable to agree upon such total production capacity or the
     relevant percentages for the Product, the parties agree to submit a
     determination to Arthur Anderson & Company for resolution of any such
     matter which shall be binding on the parties.

     These costs include:

     Manufacturing supervision and management

     Facility and Occupancy Costs

     -    Depreciation of leasehold improvements, machinery and equipment used
          in manufacturing the Product.

     -    Utilities

     -    Material handling

     -    Supplies

     -    Clerical Support

<PAGE>


                                   EXHIBIT II
                             PRODUCT SPECIFICATIONS

                               To be agreed upon.


<PAGE>


                               SECURITY AGREEMENT

     This SECURITY AGREEMENT (this "Security Agreement"), dated as of June 9 ,
1987, by and between Pfizer Inc. , a Delaware corporation, 235 East 42nd Street,
New York, New York 10017 ("Pfizer"), and Xoma Corporation, a Delaware
corporation, 2910 Seventh Street, Berkeley, California 94710 ("Xoma").

     WHEREAS, Pfizer and Xoma have entered into a License Agreement (the
"License Agreement") and a Research, Development and Option Agreement (the "R&D
Agreement"), both dated the date hereof (the License Agreement and the R&D
Agreement shall be referred to collectively as the "Agreements"), which
memorialize Xoma's agreement to grant Pfizer certain rights and options
regarding monoclonal antibodies that have been researched and developed by Xoma
and the products relating to such monoclonal antibodies; and

     WHEREAS, Xoma has agreed to secure the full and complete performance of
certain of its obligations and agreements to Pfizer under the Agreements and
this Security Agreement and the payment of any claims arising thereunder by
executing this Security Agreement, which grants to Pfizer certain hereinafter
defined security interests.

     NOW, THEREFORE, Pfizer and Xoma, in consideration of their respective
obligations and agreements stated in the Agreements and for other good and
valuable consideration, the

<PAGE>

                                       2

receipt and sufficiency of which are hereby acknowledged, agree as follows:

     1. For purposes of this Security Agreement, the following terms shall have
the meanings set forth below:

     (a) "Affiliate" means (a) any company owned or controlled to the extent of
at least fifty percent (50%) of its issued and voting capital by a party to this
Security Agreement and any other company so owned or controlled (directly or
indirectly) by any such company or the owner of any such company, or (b) any
partnership, joint venture or other entity directly or indirectly controlled by,
controlling, or under common control of, to the extent of fifty percent (50%) or
more of voting power (or otherwise having power to control its general
activities), a party to this Security Agreement, but in each case only for so
long as such ownership or control shall continue.

     (b) "E5 Product" means any product for human and/or animal therapeutic or
prophylactic use, now or hereafter developed by Xoma, which is produced (or
susceptible of being produced) from or incorporates any antibody (including
Fragments thereof as hereinafter defined) secreted from the E5 Cell Line (as
hereinafter defined) or any other cell line capable of producing said antibody,
or which product is chemically, organically, biologically or synthetically
derived from or based upon any such antibody, in each case (i) either alone or
in combination with any other therapeutic agent and (ii) together with all
pharmaceutical compositions and dosage

<PAGE>
                                       3

units thereof. For the purposes of this Section 1(b), the term "Fragments" shall
mean any part or parts of any said antibody chemically, biologically or
organically obtained from said antibody, or synthetically produced, and which
mimics the biological behavior of said antibody. For purposes of this Section
1(b), the term "E5 Cell Line" shall mean the cell line described as a murine
hybridoma as identified by American Type Culture Collection No. HB 9081 and
mutants and genetically manipulated variants thereof.

     (c) "FDA" means the United States Food and Drug Administration or any
successor governmental agency performing similar functions.

     (d) "Other Antibody Product" means any product for human and/or animal
therapeutic or prophylactic use, now or hereafter developed by Xoma, which is
produced (or susceptible of being produced) from, or incorporates any antibodies
(including Fragments thereof as hereinafter defined) secreted from the J5D4 Cell
Line and/or PCB5 Cell Line (as hereinafter defined) or any other cell lines
capable of producing any such antibodies, or which product is chemically,
organically, biologically or synthetically derived from or based upon any such
antibodies, in each case (i) either alone or in combination with any other
therapeutic agent and (ii) together with all pharmaceutical compositions and
dosage units thereof. For purposes of this Section 1(d), the term "Fragments"
shall mean any part or parts of any said antibodies chemically, biologically or
organically obtained from said antibodies, or

<PAGE>
                                       4

synthetically produced, and which mimics the biological behavior of said
antibodies. For purposes of this Section 1(d), the term "J5D4 Cell Line" shall
mean the cell line described as a murine hybridoma as identified by American
Type Culture Collection No. HB 9083 and mutants and genetically manipulated
variants thereof; and the term "PCB5 Cell Line" shall mean the cell line
described as a murine hybridoma as identified by American Type Culture
Collection No. HB 8909 and mutants and genetically manipulated variants thereof.

     (e) "Other Septic Shock Product" means any product, now or hereafter
developed by Xoma, for the treatment, cure or prevention of Septic Shock, other
than any E5 Product or any Other Antibody Product.

     (f) "Patents" means (i) all patents listed in Appendix A, annexed hereto
and made a part hereof, and any patents which may issue from the applications
listed on Appendix A, in each case together with any divisionals, continuations,
continuations-in-part, reissues, patents of addition and extensions thereof, and
(ii) all other patents and applications in the Territory now owned or controlled
by, or licensed to, or hereafter during the term of this Security Agreement
owned or controlled by, or licensed to, Xoma that are used in or related to any
E5 Product, Other Antibody Product, and/or Other Septic Shock Product or methods
of use or manufacturing processes for any E5 Product, Other Antibody

<PAGE>
                                       5

Product, and/or Other Septic Shock Product, together with any divisionals,
continuations, continuations-in-part, reissues, patents of addition and
extensions thereof.

     (g) "PLA" means a Product License Application or such other application as
shall be required to obtain Product Approval for any E5 Product, Other Antibody
Product, and/or Other Septic Shock Product.

     (h) "PLA Submission" means the submission to FDA by Xoma of a PLA which has
been prepared in good faith by Xoma in a reasonable manner to comply with FDA
requirements necessary to obtain Product Approval.

     (i) "Product Approval" means final FDA approval to market commercially in
the U.S.A the specified product for use in humans.

     (j) "Septic Shock" means endotoxin mediated complications of gram negative
bacterial sepsis.

     (k) "Supply Agreement" means the agreement so named of even date herewith
between Pfizer and Xoma.

     (l) "Technical Information" means all of Xoma's trade secrets, information,
and know-how, now owned, licensed or controlled or hereafter acquired,
developed, owned, licensed or controlled by Xoma during the term of this
Security Agreement, with respect to (i) the medical, clinical, toxicological or
other scientific data or information used in or related to any E5 Product, Other
Antibody Product, and/or Other Septic Shock

<PAGE>
                                       6

Product (including, without limitation, pre-clinical and clinical data, notes,
reports, models, and samples) and (ii) the manufacture, production, and
purification procedures and processes, as well as analytical methodology, used
in or related to the testing, assaying, analysis, production, and packaging of
any E5 Product, Other Antibody Product, and/or Other Septic Shock Product.
Technical Information shall also include: (i) Xoma's actual cell lines and
hybridomas used or useful in the production of any E5 Product, Other Antibody
Product, and/or Other Septic Shock Product and (ii) Xoma's other general
intangibles (excluding rights to payment), information, and non-patent
proprietary rights (to the extent not already included in this definition of
Technical Information) arising out of, used in or related to any E5 Product,
Other Antibody Product, and/or Other Septic Shock Product.

     (m) "Territory" means all countries of the world.

     (n) "University of California License" means the License Agreement for
Monoclonal Antibodies to Gram Negative Sepsis-Related Bacteria and Human
Diagnostics and Therapeutics Derived Therefrom, effective September 3, 1986,
between Xoma and The Regents of the University of California.

     2. In addition to the definitions stated in Section 1 of this Security
Agreement, the term "Security", for the purposes of this Security Agreement,
means, collectively, the following property of Xoma to the full extent of Xoma's
rights and interests therein, now owned, licensed or controlled or

<PAGE>
                                       7

hereafter acquired, owned or controlled by Xoma, and any proceeds of such
property: (a) all Technical Information, (b) all Patents, (c) all licenses (and
sublicenses) that have been granted to or by Xoma that are used in or related to
any E5 Product, Other Antibody Product, and/or Other Septic Shock Product
including, without limitation, the University of California License (the
property described in this Subsection (c) shall be referred to collectively as
the "Licenses"; for the purposes of this Security Agreement the terms
sublicense, sublicensee and sublicensed are included and encompassed within the
terms license, licensee, and licensed, respectively), (d) all information,
applications, instruments, authorizations, and other property of Xoma that would
be required to be submitted to any governmental agency in the Territory in order
to be granted permission or authority to manufacture, produce or sell any E5
Product, Other Antibody Product, and/or Other Septic Shock Product including,
without limitation, the information, applications, instruments, authorizations,
and other property of Xoma used in or related to any Product Approval, PLA or
PLA Submission, (e) all approvals, consents, permits, product license
applications, and authorizations of Xoma (or received by or granted to Xoma) to
manufacture, produce or sell any E5 Product, Other Antibody Product, and/or
Other Septic Shock Product including, without limitation, any "orphan drug
designation" under Section 526 of the Federal Food, Drug and Cosmetic Act, as
amended, or any other similar legislation in the Territory, (f) all claims,
causes of action, and lawsuits

<PAGE>
                                       8

belonging to Xoma arising from, related to or connected with the Technical
Information, the Patents, and/or the Licenses; provided, however, Xoma may
handle such claims, causes of action, and lawsuits in a manner that those
claims, causes of action, and lawsuits included and encompassed within the
Security are separate and segregatable from those that relate to Xoma's
properties that are not Security, and this Subsection (f) shall not be deemed to
convert assets that are not Security into Security merely because any claims,
causes of action or lawsuits are combined into one lawsuit, (g) the equipment of
Xoma described in Appendix B, annexed hereto and made a part hereof
(collectively the "Equipment"), and (h) all of Xoma's inventory of (i) E5
Products, Other Antibody Products, and Other Septic Shock Products (including,
without limitation, the purified active bulk of any E5 Product, Other Antibody
Product, and/or Other Septic Shock Product) and (ii) the actual cell lines used
in or related to the manufacture, production and purification of E5 Products,
Other Antibody Products, and Other Septic Shock Products.

     For purposes of this Security Agreement, the term "proceeds" includes,
without limitation, whatever is receivable or received when the Security or
proceeds of such Security is sold, licensed, collected, exchanged or otherwise
disposed of, whether such disposition is voluntary or involuntary, and includes,
without limitation, all proceeds consisting of receivables, accounts, general
intangibles, documents, instruments, chattel paper, rights to payment, money,
contract

<PAGE>
                                       9

or license rights, notes, proceeds, products, revenues, and returned premiums
with respect to any insurance related thereto.

     For purposes of this Security Agreement, Security shall constitute "Foreign
Security" to the extent that the perfection or priority of Pfizer's security
interests and liens (or any other rights or interests to be acquired by Pfizer
under this Security Agreement) in the Security is not governed by the law of the
United States or any political subdivision within the United States (hereinafter
the laws of any jurisdiction other than the United States or any political
subdivision within the United States shall be referred to collectively as the
"Foreign Laws").

     3. As security for Xoma's full and complete performance of its agreements
and obligations to Pfizer under the Agreements and this Security Agreement and
the payment of any claims arising under the Agreements and this Security
Agreement (collectively the "Secured Obligations"), Xoma hereby grants to Pfizer
a security interest in the Security (including, without limitation, the Foreign
Security), wherever located or situated in the Territory, and the proceeds
thereof; provided, however, nothing in this Security Agreement shall be deemed
(i) to cause the Foreign Security not to be included or encompassed within the
Security or not to be subject to the rights or interests granted to Pfizer
pursuant to this Security Agreement or (ii) to require Xoma to suffer or permit
disclosure of any document, information or asset to Pfizer of

<PAGE>
                                       10

any other party in violation of any license agreement or other contract or
obligation of Xoma.

     4. Xoma represents and warrants to Pfizer as of the date of this Agreement
as follows: (a) the tangible Security is located at 890 Heinz Street, Berkeley,
California 94710, (b) Xoma's principal place of business is at 2910 Seventh
Street, Berkeley, California 94710, and Xoma also conducts business at the
following locations: 890 Heinz Street, Berkeley, California 94710 and 2840
Eighth Street, Berkeley, California 94710, (c) Xoma has title to the Security
(including any as licensee), free and clear of all mortgages, liens, charges,
encumbrances, equities, assignments or security interests of any kind other than
as granted or created in favor of Pfizer by this Security Agreement, and no
financing statement or other similar type of filing, other than a financing
statement or a filing in the United States Patent and Trademark Office naming
Pfizer as the secured party or the assignee or mortgagee of any Patent, is now
on file in any public office, (d) Xoma has no Affiliate that has any rights or
interests in any of the Security or rights or interests in any property that
would be included or encompassed within the Security if any such rights or
interests were held by Xoma, (e) no person or other entity has any rights or
interests in any of the Security, and Xoma has not granted, or agreed to grant,
to any person or other entity any rights or interests in any of the Security,
(f) Xoma has the corporate power to make this Security Agreement and to grant
the security interests and

<PAGE>
                                       11

liens hereunder and such security interests and liens shall constitute (to the
extent possible under the laws of the United States or any political subdivision
in the United States) first valid and perfected security interests and liens on
the Security and, to the extent possible under the Foreign Laws and where
specifically required by Pfizer to be perfected or protected under the Foreign
Laws, shall constitute first valid and perfected security interests and liens on
the Foreign Security subject to no consensual prior security interests or liens,
and this Security Agreement has been duly authorized by all necessary corporate
action of Xoma and does not violate any provision of law or of the charter or
by-laws of Xoma or any contract, license or agreement to which Xoma is a party
or by which it is bound, and (g) Xoma's representations and warranties in the
Agreements are true and correct as of the date hereof.

     5. So long as this Security Agreement and the rights and interests,
including security interests and liens, created hereunder shall remain in
effect, unless Pfizer shall otherwise consent in writing, Xoma hereby covenants
and agrees with Pfizer as follows:

          (a) Xoma shall give Pfizer not leas than thirty (30) days prior
     written notice of any change of its name, in the location of its chief
     executive office, any location where it conducts business, or the location
     where it keeps any of the Security or any of the records related thereto or
     of any change in Xoma's circumstances that affects or

<PAGE>
                                       12

     may affect the continuing efficacy of any financing statement or other
     document filed by Xoma or Pfizer or, subject to Pfizer's specific
     instructions for perfection or protection of any Foreign Security under the
     Foreign Laws, the continuing status of Pfizer's security interests and
     liens as the first valid and perfected security interests and liens on the
     Security in the U.S.A. and the continuing status of Pfizer's security
     interests and liens as the first valid and perfected consensual security
     interests and liens on the Security in countries other than the U.S.A.;
     provided, however, Pfizer shall pay the reasonable out-of-pocket costs and
     expenses incurred by Xoma in complying with Pfizer's instructions for
     perfecting or protecting Pfizer's rights and interests in any Foreign
     Security under the Foreign Laws. Xoma shall promptly notify Pfizer of the
     need for Pfizer under the laws of the United States or any political
     subdivision within the United States to take any action or to execute any
     financing statement, filing, application, assignment, registration, notice,
     document of further assurances or other document or writing to perfect or
     protect the rights and interests of Pfizer in any Security that is
     hereafter acquired, controlled or owned by Xoma including, without
     limitation, prompt notice of the need to take any action or to file any
     document or writing to perfect or protect Pfizer's rights and interests in
     any Patent in the United States or any political subdivision within the
     United

<PAGE>
                                       13

     States and prompt notice of the filing of any application for a Patent
     anywhere in the Territory. Xoma shall give notice to Pfizer on the first
     business day of every other month of its activities in countries other than
     the U.S.A. to enable Pfizer to specify any action it requires Xoma to take
     under the Foreign Laws to perfect or protect Pfizer's rights and interests
     in the Foreign Security; provided, however, nothing in this Subsection (a)
     shall restrict or limit Xoma's other obligations or agreements under this
     Security Agreement. Xoma shall take such action as Pfizer may reasonably
     require to perfect or protect Pfizer's rights and interests in the Foreign
     Security, and Pfizer shall pay the reasonable out-of-pocket costs and
     expenses incurred by Xoma in taking any such action.

          (b) Xoma shall not breach, default or wrongfully terminate any
     agreement, contract, lease or license that is encompassed or included in
     the Security where such action could have any material adverse effect on
     the rights and interests of Pfizer, and Xoma shall give Pfizer written
     notice of any allegation or assertion by any other party that Xoma has so
     breached, defaulted or improperly terminated any such agreement, contract,
     lease or license within five (5) business days of the making of such
     allegation or assertion in the case of material matters and within fifteen
     (15) business days in other cases. Xoma may terminate any license it has
     granted to others that is included or encompassed within the Security in
     accordance

<PAGE>
                                       14

     with its terms where it is commercially reasonable and does not have any
     material adverse effect on Pfizer's rights and interests in the Security
     and where Xoma has given Pfizer fifteen (15) business days notice of such
     intended termination; provided, however, nothing in this provision or any
     other provision of this Security Agreement shall restrict or limit Xoma's
     obligations, or waive such obligations, under Section 2.4 of the R&D
     Agreement and Section 8 of the License Agreement. Xoma shall also give
     Pfizer five (5) business days written notice of its intent to breach,
     default, terminate, reject or repudiate any such agreement, contract, lease
     or license. Xoma shall not create or suffer to exist or permit any
     mortgage, pledge, lien, charge, encumbrance, equity, assignment or security
     interest (other than non-consensual liens or interests on the Foreign
     Security that arise in the normal course of Xoma's business) upon or in
     respect of the Security and, subject to the provisions of Section 5(a) of
     this Security Agreement regarding the Foreign Security, shall take any and
     all actions necessary to perfect or protect the rights and interests of
     Pfizer in the Security including, without limitation, (i) paying all claims
     and charges that in Pfizer's reasonable opinion might prejudice, imperil or
     adversely affect the Security in any significant respect or any security
     interest or lien of Pfizer in the Security, (ii) reasonably curing any
     breaches or defaults relating to or arising out of the Security, and (iii)
     commencing or
<PAGE>
                                       15

     processing any patent applications or infringement or misappropriation
     proceedings or lawsuits relating to the Security in a manner not
     inconsistent with the License Agreement. Pfizer acknowledges that Xoma may
     conduct its business outside the United States in the ordinary course even
     though certain of the Foreign Laws may create non-consensual liens and
     encumbrances senior or junior to those of Pfizer. Xoma shall not under any
     circumstances permit any Equipment to become a fixture by attachment to any
     real property, unless such Equipment is described on any financing
     statement filed as a mortgage or fixture filing perfecting Pfizer's
     security interests and liens on such Equipment.

          (c) Xoma shall not sell or otherwise dispose of any rights or
     interests in or to any of the Security other than as permitted by the terms
     of this Subsection (c), Section 5(b) or (d) of this Security Agreement or
     with Pfizer's written consent, which consent shall not be unreasonably
     withheld in the case of the disposal of obsolete or practically worthless
     tangible property, in the case of the settlement of litigation or disputes
     with third parties, or in the case of the trade-in of equipment that does
     not affect any material portion of the Security. Xoma may use and spend
     cash proceeds of the Security in the ordinary course of business as long as
     no Event of Default (as such term is defined in Section 10 of this Security
     Agreement) occurs and is continuing. Nothing in this

<PAGE>
                                       16

     Security Agreement shall be deemed to limit or restrict Pfizer's rights and
     interests under the License Agreement, the R&D Agreement, and the Supply
     Agreement.

          (d) Xoma shall not grant, or agree to grant, to any Affiliate any
     rights or interests in any of the Security or to cause any Affiliate to own
     any rights or interests in any property that would be included or
     encompassed within the Security if any such rights and interests were held
     by Xoma. Notwithstanding any other provision of this Security Agreement,
     Xoma, prior to an Event of Default, shall be permitted to license
     (exclusively or nonexclusively) to any person or entity any of the
     Security, including the Technical Information and the Patents, subject to
     the rights and interests of Pfizer created by this Security Agreement and
     subject to and not inconsistent with Pfizer's rights and interests under
     the License Agreement, the R&D Agreement, and the Supply Agreement. Xoma
     shall not secure the performance of any of its obligations or agreements
     under any such license permitted under the immediately preceding sentence
     of this Subsection (d) or the payment of any claims arising under such
     license by creating or suffering to exist or permitting any mortgage,
     pledge, lien, charge, encumbrance, equity, assignment or security interest
     upon or in respect of any of the Security.

<PAGE>
                                       17

          (e) To the extent reasonably desirable for the protection of Pfizer's
     rights and interests in the Security, Xoma shall keep accurate and complete
     records of the Security and, after any Event of Default, the proceeds
     therefrom and, after any Event of Default, shall keep the Security and the
     proceeds therefrom separate and distinct from its other property. After any
     Event of Default shall have occurred, Xoma shall account for, and, promptly
     deliver to Pfizer, in the form received, all proceeds of the Security
     received, endorsed to Pfizer as appropriate, and until so delivered, all
     proceeds shall be held by Xoma in trust for Pfizer, separate and apart from
     all other property of Xoma and identified as the Security of Pfizer.

          (f) Risk of loss of the Security shall be on Xoma, and the loss,
     injury or destruction of the Security shall not release Xoma hereunder. To
     the extent commercially reasonable, Xoma shall insure the Equipment in such
     amounts and against such risks, as Pfizer shall reasonably deem acceptable,
     and Xoma shall deposit complete insurance policies or copies thereof with
     Pfizer; provided, however, Pfizer has agreed that Xoma's current insurance
     policies on the Equipment are commercially reasonable.

<PAGE>
                                       18

     Pfizer shall be named as an insured and loss payee under such insurance
     policies. If Xoma fails to obtain appropriate insurance covering the
     Equipment in a timely fashion, Pfizer may, but shall not be obligated to,
     obtain such insurance and the cost thereof shall be immediately due and
     owing from Xoma to Pfizer and shall become a Secured Obligation and, at
     Pfizer's option, set-off against any amounts owing to Xoma under the
     License Agreement or Supply Agreement. Xoma hereby irrevocably appoints
     Pfizer as its agent to adjust all insurance losses, to sign all
     applications, receipts, releases, and other papers necessary to collect any
     such loss and any return or unearned premium, to execute proofs of loss, to
     make settlements, to endorse and collect any check or other item payable to
     Xoma issued in connection therewith, and to apply the same to payment of
     the debt; provided, however, Pfizer may exercise the rights set forth in
     this sentence of this Subsection (f) only after an Event of Default.

          (g) Without limiting the generality of the foregoing, promptly upon
     Pfizer's request, Xoma shall sign and execute together, alone or with
     Pfizer, as Pfizer shall determine, any financing statement, filing,
     application, assignment, registration, notice, document of further
     assurances or other document or writing or take such other additional
     actions as Pfizer may reasonably require to perfect or protect the rights
     and interests of Pfizer in the Security (including, without limitation,
     making any

<PAGE>
                                       19

     filing with the United States Patent and Trademark Office that may be
     requested by Pfizer or assigning to Pfizer any application, instrument or
     authorization that seeks or grants approval or authority for the
     manufacture, production or sale of any E5 Product, Other Antibody Product,
     and/or Other Septic Shock Product). Except after an Event of Default,
     nothing in this Security Agreement shall accelerate or expand Xoma's
     disclosure obligations beyond those obligations set forth in other
     agreements between Xoma and Pfizer; provided, however, (i) Xoma shall
     provide to Pfizer notice of the filing of any application for a Patent or
     the issuance of any Patent anywhere in the Territory and (ii) Xoma shall
     provide to Pfizer all information that is reasonably necessary for Pfizer
     to perfect its security interests and liens in the Security. Xoma, however,
     hereby irrevocably appoints Pfizer as its agent to execute such documents
     or take such other action as is reasonably necessary to perfect or protect
     Pfizer's rights and interests in the Security. Xoma shall not file or
     authorize to be filed in any jurisdiction in the Territory or with any
     public office any financing statement, filing, application, assignment,
     registration, notice, document of further assurances or other document or
     writing relating to the Security in which Pfizer is not named as the sole
     secured party or assignee; provided, however, Xoma may record or file any
     Existing License (as such term is defined in Section 7 of this Security

<PAGE>
                                       20


         Agreement) if (i) such recording or filing does not have the effect of
         perfecting or creating a security interest or lien in the Security and
         (ii) such recording or filing would be subject to and not inconsistent
         with the rights and interests of Pfizer created by this Security
         Agreement and subject to and not inconsistent with the provisions of
         Section 7 of this Security Agreement. Notwithstanding anything to the
         contrary in this Security Agreement, Xoma shall not be required to
         file, prosecute, enforce or maintain any Patent or any application for
         a Patent except to the extent required by the Agreements; provided,
         however, nothing in this sentence of this Subsection (g) shall affect,
         limit or restrict (i) whatever rights or remedies Pfizer may possess
         after an Event of Default under this Security Agreement or under law or
         equity and (ii) Xoma's obligations and agreements after an Event of
         Default.

          (h) Xoma shall keep the Equipment in good condition and repair, normal
     wear and tear excepted. Subject to the provisions of Section 5(c) of this
     Security Agreement, Xoma shall do all acts that may be reasonable and
     necessary to maintain, preserve, and protect the Security that is tangible
     personal property, including the payment of all repair, maintenance, and
     preservation costs relating to the Security. Xoma shall pay promptly when
     due all taxes, assessments, charges, encumbrances, levies, and liens now or
     hereafter imposed upon or affecting the Security subject to Xoma's right to
     contest in good faith

<PAGE>
                                       21

     any such claim or lien and to defer payment pending the resolution of such
     contest unless Pfizer's rights or interests in the Security shall be
     materially threatened or diminished by such deferral of payment.

          (i) Xoma shall not use or permit any Security to be used unlawfully or
     in violation of any provision of this Security Agreement, or any applicable
     statute, regulation or ordinance or any policy of insurance covering the
     Security. To the extent not inconsistent with the License Agreement or any
     other written agreement between Pfizer and Xoma, Xoma shall appear in and
     defend any proceedings or lawsuits that may affect its right, title or
     interest to the Security or Pfizer's rights or interests in the Security in
     the United States and, at Pfizer's expense, any other country in the
     Territory where directed to by Pfizer.

     6. After an Event of Default has occurred, Pfizer, at its option, may, in
its name or in the name of Xoma or otherwise, demand, sue for, collect or
receive any money or property at any time payable or receivable on account of or
in exchange for, or make any compromise or settlement deemed desirable with
respect to, any of the Security, but Pfizer shall be under no obligation to do
so, or Pfizer may extend the time of payment, arrange for payment in
installments, or otherwise modify the terms of, or release, any of the Security,
without thereby incurring responsibility to, or discharging or otherwise
affecting any liability of Xoma.

<PAGE>
                                       22

     7. After an Event of Default has occurred, Pfizer may also, at its option
and without notice to or demand on Xoma, and in addition to all rights and
remedies available to Pfizer as a secured party, at law or in equity or
otherwise, (a) foreclose or otherwise enforce Pfizer's security interests and
liens or other rights and interests in the Security in any manner permitted by
law or provided for in this Security Agreement, (b) sell or otherwise dispose of
the Security or any part thereof or interest therein at one or more public or
private sales at Pfizer's place of business or any other place or places,
whether or not such Security is present at the place of sale, for cash or credit
or future delivery, on such terms and in such manner as Pfizer may reasonably
determine, (c) recover from Xoma the reasonable costs and expenses (including,
without limitation, attorneys' fees) reasonably incurred or paid by Pfizer in
exercising any right, power or remedy provided by law or this Security Agreement
(including, without limitation, the reasonable costs and expenses incurred in
assembling, taking, repairing or selling the Security or any part thereof), (d)
require Xoma to promptly assemble the Security and all information, books,
records, and other materials relating thereto and make such available to Pfizer
at a place to be designated by Pfizer, (e) enter onto the property where any
Security is located and take possession thereof with or without judicial
process, (f) cure any breach, default or improper termination of any agreement,
contract, lease or

<PAGE>
                                       23

license of Xoma that is included or encompassed in the Security, (g) substitute
itself for Xoma in any proceeding or lawsuit included or encompassed within,
arising from, related to or connected with the Security or Pfizer's rights and
interests in it (including, without limitation, substituting itself for Xoma in
any proceeding seeking the approval of any application for a Patent or any
proceeding seeking approval or authority for the manufacture, production or sale
of any E5 Product, Other Antibody Product, and/or Other Septic Shock Product) or
commence, on behalf of Xoma and in Xoma's name, any proceeding or lawsuit to
protect the Security or Pfizer's rights and interests in it, and (h) prior to
the disposition of the Security, prepare it for disposition in any manner and to
the extent Pfizer deems appropriate. Xoma shall be given ten (10) business days
prior written notice of the time and place of any public sales or of the time
after which any private sales or other intended dispositions are to be made,
which notice Xoma hereby agrees shall be deemed reasonable notice thereof;
provided, however, Pfizer shall not be required to give such notice in the case
of any Security that Pfizer in good faith determines to be declining speedily in
value. Upon any sale or other disposition pursuant to this Security Agreement,
Pfizer shall have the right to deliver, assign, and transfer to the purchaser
thereof the Security or portion thereof so sold or disposed of by Pfizer. Each
purchaser at any such sale or other disposition (including Pfizer) shall

<PAGE>

                                       24

hold the Security free from any claim or right of whatever kind, including any
equity or right of redemption of Xoma.

     Notwithstanding any of the provisions of this Security Agreement, Pfizer
(for the purposes of this second paragraph of this Section 7 the term "Pfizer"
means Pfizer and its Affiliates, successors, and assigns) covenants for the
benefit of Xoma and any licensee or sublicensee of any of the Security from Xoma
that, in or after exercising its rights and remedies under this Security
Agreement, Pfizer shall not sue for infringement or misappropriation any person
or other entity (a "Licensee") that has licensed or sublicensed rights in any of
the Security, including any of the Patents and Technical Information, from Xoma
pursuant to a license (or sublicense) (an "Existing License") that is not
inconsistent with or contrary to the provisions of Section 5(d) of this Security
Agreement so long as (i) Xoma or Pfizer, as Xoma's successor in interest, has no
right to terminate such Existing License with such Licensee pursuant to the
terms and conditions of such Existing License or otherwise, including, without
limitation, any rightful repudiation (by words or action) or termination by Xoma
of its obligations, covenants or agreements with such Licensee under an Existing
License, and (ii) Xoma has not rejected its agreement with such Licensee under
an Existing License pursuant to Section 365 of the Bankruptcy Code, 11 U.S.C ss.
365; provided, however, subject to Pfizer's agreement stated in this first
sentence of this second paragraph of this

<PAGE>

                                       25

Section 7, nothing in this Section 7 shall restrict or limit in any fashion or
manner whatsoever (i) Pfizer's rights and interests (including security
interests and liens) in the proceeds of any Existing License and the claims,
causes of action or lawsuits included or encompassed within the Security, (ii)
Pfizer's rights and remedies against a Licensee arising under either an Existing
License, this Security Agreement, the Agreements or otherwise, (iii) the
description and scope of the Security granted to Pfizer pursuant to Section 2 of
this Security Agreement, and (iv) Pfizer's rights or interests in any of the
Security (including, without limitation, all claims and fields of use included
or encompassed within any of the Patents and any of the Technical Information)
or Pfizer's rights or remedies against the Security or Xoma under this Security
Agreement or otherwise.

     8. After an Event of Default has occurred, Xoma shall pay to Pfizer all
reasonable expenses of, or incidental to, the enforcement or application of any
of the provisions hereof, or any actual or attempted sale, or any exchange,
enforcement, collection, compromise or settlement of any of the Security or
receipt of the proceeds thereof, and for the care of the Security and defending
or asserting the rights and claims of Pfizer in respect thereof, by litigation
or otherwise, including, without limitation, reasonable attorneys' fees and
insurance expenses; and all such expenses shall be Secured Obligations within
the terms of this Security Agreement and, at

<PAGE>
                                       26

Pfizer's option, set-off against any amounts owing to Xoma under the License
Agreement or Supply Agreement.

     9. No delay on the part of Pfizer in exercising any power or right
hereunder shall operate as a waiver thereof; nor shall any single or partial
exercise of any power or right hereunder preclude other or further exercise
thereof or the exercise of any other power or right. The rights, remedies, and
benefits herein expressly specified are cumulative and not exclusive of any
rights, remedies or benefits that Pfizer may otherwise have. Xoma hereby waives
presentment, notice of dishonor, and protest of all instruments included in or
evidencing Xoma's liability for payment or performance of the Secured
Obligations or the Security and any and all other notices and demands
whatsoever, whether or not related to such instruments. Xoma hereby waives, to
the full extent permitted by law, the right to plead any statute of limitations
as a defense to any action or proceeding for the enforcement hereof, or for the
enforcement of any of the Secured Obligations.

     10. For purposes of this Security Agreement, an "Event of Default" shall be
deemed to occur if (a) Xoma shall materially breach or materially default in the
performance or observance of any of its material obligations, covenants or
agreements under Section 4.1 and Section 4.2 of the R&D Agreement, and such
breach or default is not cured within the cure period following notice thereof
as provided therein, (b) Xoma shall materially breach or materially default in
the

<PAGE>
                                       27

performance or observance of any of its material obligations, covenants or
agreements under the License Agreement, and such breach or default is not cured
within the cure period following notice thereof as provided therein, (c) Xoma
shall breach or default in the performance of or observance of any of its
obligations, covenants or agreements under Section 5(d) of this Security
Agreement or (d) Pfizer obtains a judgment for money or specific performance
against Xoma arising out of Xoma's breach or default in the performance of its
obligations, covenants or agreements under this Security Agreement (other than
Section 5(d) of this Security Agreement) and such judgment goes unsatisfied for
a period of thirty (30) days after the resolution of the last appeal taken by
Xoma of such judgment; provided, however, nothing in this Section 10 shall
restrict or limit Pfizer's right to bring an action in equity or law against
Xoma for its breach or default of any of its obligations, covenants or
agreements set forth in this Security Agreement or in the Agreements.

     11. No provision hereof shall be modified or limited except by a written
instrument expressly referring hereto and to the provision so modified or
limited. This Security Agreement shall be binding upon the successors and
assigns of Xoma and Pfizer and shall be assignable by Pfizer to any of its
Affiliates. Xoma and Pfizer intend to bind any subsequent purchaser of the
Security in accordance with the provisions of Section 17 of this Security
Agreement.

<PAGE>
                                       28

     12. No course of dealing, omission or delay of Pfizer in the exercise of
any right, power or privilege referred to in this Security Agreement or in
either of the Agreements shall operate as a waiver hereof, nor shall any partial
exercise thereof preclude any further exercise thereof, as Pfizer may exercise
each such right, power or privilege either independently or concurrently and as
often and in such order as Pfizer deems expedient. Nothing in the Agreements and
the Supply Agreement shall be deemed to limit or restrict Pfizer's remedies,
rights and interests under this Security Agreement.

     13. Any notice, consent or approval required under this Security Agreement
shall be in writing sent by registered or certified airmail, postage prepaid, or
by telex or cable (confirmed by such registered or certified mail) and addressed
as follows:

If to Pfizer:                               If to Xoma:

Pfizer Inc.                                 Xoma Corporation
235 East 42nd Street                        2910 Seventh Street
New York, New York 10017                    Berkeley, California  94710
Telex:  420440                              Telex:  856-697
Attention:  General Counsel                 Attention:  Chairman

All notices shall be deemed to be effective on the date of mailing. In case any
party changes its address at which notice is to be received, written notice of
such change shall be given without delay to the other party.

     14. If Pfizer, pursuant to Sections 4, 6.1 or 10.2 of the R&D Agreement or
Section 9.03 of the License Agreement (or in the case of an Other Septic Shock
Product accepted under

<PAGE>
                                       29

Section 4.2 of the R&D Agreement in accordance with the terms of a license
agreement between Pfizer and Xoma with respect thereto), (a) rejects its option
to acquire rights to any Other Antibody Product or Other Septic Shock Product or
terminates its rights or licenses with respect to any such Other Antibody
Product or Other Septic Shock Product or any E5 Product (the "Rejected or
Terminated Product") and (b) Pfizer no longer has any right under the R&D
Agreement to exercise an option at any time in the future to acquire such rights
to such Rejected or Terminated Product or to acquire any other rights or
interests in such Rejected or Terminated Product, (i) such Rejected or
Terminated Product shall no longer be included or encompassed within the
Security if it is in no fashion or manner otherwise included or encompassed
within the Security and (ii) any Security that is exclusively and solely used in
and related to such Rejected or Terminated Product and is in no fashion or
manner used in and related to any E5 Product, Other Antibody Product, and/or
Other Septic Shock Product (which is not a Rejected or Terminated Product) shall
also not be included or encompassed within the Security (the "Rejected or
Terminated Security"). Pfizer shall execute any financing statement, filing,
application, assignment registration, notice, document of further assurances or
other document or writing to evidence Pfizer's lack of rights or interests in
any Rejected or Terminated Product and any Rejected or Terminated Security.


<PAGE>
                                       30

     15. If it should appear that any provisions of this Security Agreement are
in conflict with any statute or rule of law of any jurisdiction wherein it may
be sought to be enforced, then such provisions shall be deemed null and void to
the extent that they conflict therewith, but without invalidating the remaining
provisions hereof.

     16. This Security Agreement and the rights and obligations of the parties
hereunder shall be construed in accordance with and governed by the laws of the
State of California.

     17. To state and evidence the agreements between Xoma and Pfizer embodied
in this Security Agreement, any financing statement or filing made by Pfizer (or
any of its Affiliates) with any governmental authority in the Territory
(including, without limitation, any UCC-1 financing statement) to perfect or
protect Pfizer's rights and interests in the Security shall include the
following language:

         Subject to the terms and conditions of a certain Security Agreement
         (the "Security Agreement") between Pfizer Inc. (including its
         Affiliates (as such term is defined in the Security Agreement),
         successors, and assigns) ("Pfizer") and Xoma Corporation ("Xoma"),
         Pfizer and Xoma intend that the Security Agreement shall bind Pfizer
         and any subsequent purchaser of the Security (as such term is defined
         in the Security Agreement) that purchases the Security pursuant to, and
         after, Pfizer's exercise of its rights and remedies under the Security
         Agreement from suing for infringement or misappropriation any person or
         other entity (a "Licensee"; this is the meaning given such term in the
         Security Agreement) that has licensed or sublicensed rights in any of
<PAGE>
                                       31

         the Security, including any of the Patents and Technical Information
         (as such terms are defined in the Security Agreement), from Xoma
         pursuant to a license (or sublicense) (an "Existing License"; this is
         the meaning given such term in the Security Agreement) that is not
         inconsistent with or contrary to the provisions of Section 5(d) of the
         Security Agreement so long as (i) Xoma or Pfizer, as Xoma's successor
         in interest, has no right to terminate such Existing License with such
         Licensee pursuant to the terms and conditions of such Existing License
         or otherwise, including, without limitation, any rightful repudiation
         (by words or action) or termination by Xoma of its obligations,
         covenants or agreements with such Licensee under an Existing License,
         and (ii) Xoma has not rejected its agreement with such Licensee under
         an Existing License pursuant to Section 365 of the Bankruptcy Code, 11
         U.S.C ss. 365; provided, however, subject to Pfizer's agreement stated
         in the first sentence of the second paragraph of Section 7 of the
         Security Agreement, nothing in Section 7 of the Security Agreement
         shall restrict or limit in any fashion or manner whatsoever (i)
         Pfizer's rights and interests (including security interests and liens)
         in the proceeds of any Existing License and the claims, causes of
         action or lawsuits included or encompassed within the Security, (ii)
         Pfizer's rights and remedies against a Licensee arising under either an
         Existing License, the Security Agreement, the Agreements (as such term
         is defined in the Security Agreement) or otherwise, (iii) the
         description and scope of the Security granted to Pfizer pursuant to
         Section 2 of the Security Agreement, and (iv) Pfizer's rights or
         interests in any of the Security (including, without limitation, all
         claims and fields of use included or encompassed within any of the
         Patents and any of the Technical Information) or Pfizer's rights or
         remedies against the Security or Xoma under the Security Agreement or
         otherwise.

     18. This Security Agreement shall terminate at such time that (a) Xoma
shall have fully performed and complied with, in all material respects, all of
its material obligations

<PAGE>
                                       32

and agreements with Pfizer under the License Agreement (other than any
obligation or agreement stated in Section 10.01 of the License Agreement) and
Section 4.1 of the R&D Agreement and Pfizer, under the Agreements, shall have no
rights or interests (including, without limitation, future rights, interests of
expectancies) in any E5 Product and/or any Other Antibody Product and Pfizer
shall have no right to obtain any such rights or interests; (b) no Event of
Default shall exist and be occurring; (c) no claim or cause of action arising or
resulting from any Event of Default shall exist; and (d) no lawsuit or appeal
thereof that is or could be encompassed in Section 10(d) of this Security
Agreement shall exist or be pending (the events, claims, and occurrences
described in or encompassed or included within Subsections (a) through (d) of
this Section 18 shall hereinafter be referred to collectively as the "Continuing
Obligations"). In the event that Pfizer alleges, in the exercise of its
reasonable judgment, that this Security Agreement has not and cannot terminate
due only to the occurrence or existence of any Continuing Obligation described
in or encompassed or included within Subsection (c) or Subsection (d) of this
Section 18 (an "Open Secured Obligation"), this Security Agreement shall
terminate (in the absence of the occurrence or existence of any other Continuing
Obligation, including any Open Secured Obligation) if, without admitting the
existence or merit of any disputed Open Secured Obligation and without prejudice
to Xoma's right to dispute or

<PAGE>
                                       33

defend against any Open Secured Obligation, (i) Xoma and Pfizer agree as to the
potential liquidated amount of such Open Secured Obligation (the "Claim Amount")
and Xoma shall have provided to Pfizer a letter of credit or surety bond in the
Claim Amount, in a form and substance reasonably satisfactory to Pfizer, to
secure Xoma's full payment of such Open Secured Obligation upon entry of a final
judgment in Pfizer's favor on such Open Secured Claim or (ii) Xoma and Pfizer
agree to a mechanism or arbitrator to settle the disputes (the "Dispute
Resolution Mechanism") between them regarding the Claim Amount and the form and
substance of the letter of credit or surety bond to be given to Pfizer to secure
Xoma's full payment of such Open Secured Obligation upon entry of a final
judgment in Pfizer's favor on such Open Secured Claim and Xoma provides to
Pfizer the letter of credit or surety bond in the Claim Amount and in the form
and substance established by the Dispute Resolution Mechanism; provided,
however, in the absence of any agreement between Xoma and Pfizer as to the
Dispute Resolution Mechanism, a federal court having jurisdiction over Xoma and
Pfizer (or, if no jurisdiction shall exist in any federal court in the United
States, then the Superior Court of California for the County of Alameda) shall
serve as the Dispute Resolution Mechanism in accordance with and subject to the
provisions of Subsection (ii) of this Section 18. Nothing in this Security
Agreement shall cause this Security Agreement or the rights and interests
created hereunder to terminate or lapse or shall

<PAGE>
                                       34

cause any property of Xoma to not be included or encompassed within the Security
due to the rejection or repudiation of Xoma's obligations and agreements
(including, without limitation, a rejection under 11 U.S.C. ss. 365) stated in
this Security Agreement or either of the Agreements except in accordance with
and consistent with the express terms and provisions of such agreements.

     IN WITNESS WHEREOF, the parties hereto have caused this Security Agreement
to be duly executed as of the day and year first above written.

                             PFIZER INC.

                             By /s/William C. Steere
                                Title Vice President

                             XOMA CORPORATION

                             By /s/Steven C. Mendell
                                Title Chairman/ CEO


<PAGE>


                                                       Debtor: Xoma Corporation
                                   Appendix A
                                     Page 1

                                LICENSED PATENTS

I                                 II                             III

US 06/855,878 (2)               US 06/781,242 (1)            US 06/855,878 (2)

                                                                 (Plus foreign
                                                                 filings listed
                                                                 under Col I)
AUSTRALIA 63236/86                US 06/855,878 (2)            US 07/036,766 (3)
CANADA 519,066                    U.S. 07/036,766 (3)
EUROPE 86306420.0
  (10 EPO Countries)
IRELAND 2546/86
ISRAEL 79719
JAPAN 229481/86
KOREA 8128/86
NEW ZEALAND 217283
PHILLIPINES 34297
SOUTH AFRICA 86/7342
SPAIN 8602198
U.S. 07/036,766 (3)

(1) Filing Date 9/27/84

(2) Filing Date 4/24/86

(3) Filing Date 4/10/87


<PAGE>


                                                         Debt : Xoma Corporation
                                                                      Appendix B
                                                                          Page 1

                                   Appendix B

All equipment of Xoma Corporation ("Xoma"), now owned, leased or controlled or
hereafter acquired, owned, leased or controlled by Xoma that is used in the
purification of raw antibody into purified active antibody for the purpose of
producing and manufacturing products for supply to Pfizer, Inc. pursuant to a
certain Supply Agreement, between Pfizer and Xoma including, without limitation,
the following equipment of Xoma so long as so used or intended to be so used:


Equipment Description             Serial Number              Leased Equipment

Amicon Columns                    180-0101
                                  0309
                                  450-006
                                  300-0089
                                  180-0149
                                  NSN (1)
Masterflex Pumps                  391282
                                  401895
                                  405402
                                  426501
LXB Uvicords SII                  1723
                                  282
                                  3783                       X
                                  128
                                  3788                       X
                                  3798                       X
Chart Records:
  Kipp & Zonen                    866600
  E&K                             842476
                                  861781                     X
                                  861779                     X
                                  861778                     X
                                  861780                     X
Millipore Diafiltration
  Unit                            NSN (1)
Pharmacia Fraction
  Collector                       132012                     X
                                  132008

(1)  No Serial Number on Equipment


<PAGE>


                                                        Debtor: Xoma Corporation
                                                                      Appendix B
                                                                          Page 2

Equipment Description                    Serial Number        Leased Equipment

Lightnin Mixers                          86/271843/4
                                         86/271843/3
                                         86/271843/5
                                         MN DS3004
                                         MN DS3004

Watson-Marlow Pumps                      106149                     X
                                         105307
                                         105704                     X
                                         105311
                                         105306

Millipore High Volume Cell               NSN (1)                    X

Mettler PE22 Balance                     F12856

Sartorius Filter Housing                 3607019                    X

(1)  No Serial Number on Equipment

Nothing herein shall be deemed to grant a security interest to Pfizer in any
equipment leased to Xoma (the "Leased Equipment") except to the extent of Xoma's
rights and interests as lessee in the Leased Equipment and then only to the
extent the granting of such security interest in the Leased Equipment would not
cause a material breach of any lease between Xoma and any equipment lessor;
provided, however, Pfizer, notwithstanding any other agreement between it and
Xoma, shall have a security interest in the proceeds of any lease of the Leased
Equipment to Xoma.







                             MANUFACTURING AGREEMENT

     AGREEMENT dated as of January 1, 1991 by and between XOMA CORPORATION
("Xoma"), a Delaware corporation with principal offices at 2910 7th Street (P.O.
Box 11261), Berkeley, California 94710, and PFIZER INC ("Pfizer"), a Delaware
corporation with principal offices at 235 East 42nd Street, New York, New York
10017 and a facility at 630 Flushing Avenue, Brooklyn, New York 11206 (the
"Facility").

     WHEREAS, the defined terms used in this Agreement shall have the meanings
ascribed to them in Attachment 1 attached hereto; and

     WHEREAS, the parties desire that Pfizer perform certain manufacturing and
distribution activities pursuant to Xoma's PLA, in accordance with the terms and
subject to the conditions set forth in this Agreement;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
provided herein, Pfizer and Xoma hereby agree as follows:

1.   DESCRIPTION OF STEPS

1.01 General. The parties hereby agree that Xoma shall package, label and ship
E5 to Pfizer pursuant to Section 1.02, in accordance with the terms and subject
to the conditions set forth herein. In addition, the parties hereby agree that
Pfizer shall have the right to perform additional steps on such E5 pursuant to
Sections 1.03, 1.04, and 1.05, in accordance with the terms and subject to the
conditions set forth herein. The parties agree and acknowledge that all of the
steps to be performed by Pfizer shall be performed according to specifications
and procedures that comply with Sections 6.01 and 6.02.

1.02 Packaging, Labelling and Shipment to Pfizer. Xoma shall fill and label bulk
drug containers with E5, freeze the filled and labelled containers and ship the
frozen containers to Pfizer by Federal Express Overnight Delivery, or another
mutually agreed upon delivery service.

1.03 Steps Prior to Filling, Labelling and Packaging. Pfizer shall perform the
following steps prior to filling, labelling and packaging:

1. Receive frozen E5 from Xoma, inspect the containers and labels and store the
E5 frozen.


<PAGE>


                                       -2-

2) Review the Xoma certificate of analysis and shipping records.

3) Thaw frozen E5 under controlled conditions.

4)   Sample the E5.

1.04 Filling, Labelling and Packaging Steps. Pfizer shall perform the following
filling, labelling and packaging steps:

1)   Process the E5 by aseptic filtration.

2) Fill the E5 into sterilized vials and seal the filled vials.

3)   Conduct in-process testing, which may include fill volume, seal integrity
     and appearance.

4)   Label and package the filled vials.

5)   Sample the labelled vials.

6) Submit lot samples and Xoma test data to CBER for release.

7)   Upon approval by CBER, ship the filled, labelled and packaged E5 for
     commercial use.

8)   Maintain production records, quality control records and reserve samples as
     required.

1.05 Storage and Handling. Pfizer shall maintain the appropriate storage
conditions throughout holding and shipping of the filled and labelled E5, in
accordance with Sections 6.01 and 6.02.

2.   SUPERVISION BY XOMA

2.01 The following employee of Xoma is hereby designated as the individual
responsible for ensuring that the above operations are carried out in accordance
with the PLA and GMP:

Name:          C.L. Dellio
Title:         Senior Vice President-Operations
Address:       Xoma Corporation Headquarters
               2910 Seventh Street
               Berkeley, California  94710
Telephone
Number:        (415) 644-1170

Another employee of Xoma may be designated from time to time, provided Pfizer is
notified in advance in writing of his or her name, title, address and telephone
number. <PAGE>
                                       -3-


2.02 The individual designated by Xoma pursuant to Section 2.01 shall carry out
his responsibilities through periodic on-site visits, telephonic reports and
written memoranda. Such individual shall be assisted by Dr. Frances M.
Bogdansky, Vice President, Quality Control of Xoma, or her disignee or
replacement, who shall monitor quality control and compliance issues. Xoma will
continue to monitor Pfizer's operations as they relate to E5 by conducting
regularly scheduled audits of the Facility to assure ongoing compliance with the
PLA and GMP.

3.   STANDARD OPERATING PROCEDURES AND FORMS

3.01 All activities conducted hereunder by Pfizer will be conducted in
accordance with Standard Operating Procedures prepared by Pfizer that comply
with Sections 6.01 and 6.02.

3.02 Pfizer agrees that for each lot of E5 filled and packaged hereunder, Pfizer
shall complete and furnish to Xoma batch production records. It is acknowledged
by the parties that such records shall include test data for each lot.

3.03 Xoma agrees to maintain a complete record of information for each lot for
the period required by law, including the information referred to in Section
3.02. Xoma acknowledges that maintenance of summaries of such information, as
opposed to complete copies of the original records themselves, shall not
constitute fulfillment of the obligation referred to in the immediately
preceding sentence.

4.   DISTRIBUTION AND RECALL SYSTEM

4.01 The parties agree that, after filled and packaged E5 product has been
approved for release and placed into finished stock, it is subject to being
shipped to Pfizer's distribution centers for distribution to customers. Pfizer
will comply with Section 1.05 in holding and shipping the finished stock at and
from such distribution centers.

4.02 The parties agree that, after released E5 product has been distributed to
customers, it shall be subject to recall by Pfizer using the sales information
recorded by Pfizer's distribution centers at the time of sale.

5.   PERMISSION TO INSPECT

5.01 Pfizer hereby agrees and acknowledges that it shall permit authorized
representatives of the FDA, including without limitation authorized
representatives of the CBER, to inspect those portions of the Pfizer facilities
in which Pfizer performs the activities provided for in this Agreement.

<PAGE>
                                      -4-

6.   COMPLIANCE WITH CURRENT GMP AND PLA

6.01 Pfizer agrees that, in performing the activities provided for in this
Agreement, it shall comply with GMP.

6.02 Pfizer agrees to perform all of the activities provided for in this
Agreement in accordance with the PLA. In the event Xoma desires to modify the
PLA, Xoma agrees to notify Pfizer of the planned modifications a reasonable
period of time before the submission of such modifications to the FDA, so that
Pfizer has sufficient time to implement those modifications that affect its
activities hereunder.

7.   FDA REGISTATION OF THE FACILITY

     Pfizer shall perform the activities provided for in this Agreement at its
Brooklyn Facility, unless otherwise specified or approved in advance by Xoma and
the appropriate regulatory authorities. The Facility is registered with the FDA,
its current Drug Establishment Registration Number being 2410924.

8.   LABEL CONTROL

8.01 Pfizer acknowledges that an example of the in-process labels to be used by
Pfizer in performing the activities provided for in this Agreement are attached
hereto as Attachment 8.01. The parties agree that Pfizer has the right to modify
said labels to the extent permitted by law, upon written notice to Xoma and,
where required, after authorization by CBER.

8.02 Xoma acknowledges that copies of shipping labels to be used by Xoma in
performing the activities provided for in this Agreement are attached hereto as
Attachment 8.02. The parties agree that Xoma has the right to modify said labels
to the extent permitted by law, upon written notice to Pfizer and, where
required, after authorization by CBER.

8.03 Each party agrees to ensure that all of its labels comply with the
applicable laws and regulations including without limitation Section 351(a) (2)
of the Public Health Service Act, Biological Products, which requires, among
other things, that each package be plainly marked with a manufacturer license
number.

9.   ULTIMATE USE AND EXPORT OF E5

9.01 Pfizer represents that (a) E5 may be both shipped domestically and
exported, and (b) E5 is an injectable product.

9.02 Pfizer further represents that (a) it shall not permit the return to the
U.S. of any partially processed E5 product
<PAGE>
                                       -5-


received hereunder from Xoma that is exported by Pfizer or any E5 product
processed by Pfizer hereunder and exported by Pfizer; provided that Pfizer shall
permit the return of any such E5 product to Pfizer (b) the U.S. PLA license
number for E5 shall not appear on the labelling of the final E5 product received
or processed by Pfizer hereunder that is exported, it being acknowledged and
agreed by Pfizer that it shall not claim that any exported E5 product processed
by Pfizer hereunder meets U.S. standards, and (c) any E5 product exported by
Pfizer shall meet the specifications of the foreign purchaser and shall not be
in conflict with the laws of the importing country.

10.  TERM

This Agreement shall be effective as of the date first set forth above and shall
remain in effect for an unlimited period of time, subject to early termination
in accordance with the terms of the provisions of Section 11.

11.  TERMINATION

11.01 In the event Pfizer ceases to have the right to use or sell E5 product,
this Agreement shall terminate automatically, effective the date on which such
right ceases.

11.02 Pfizer shall have the right, exercisable in its sole discretion with or
without cause, to terminate this Agreement by giving to Xoma one (1) year's
advance written notice of termination. After giving notice of termination and
throughout the year ending on the date the notice of termination becomes
effective, Pfizer agrees to render its reasonable cooperation and assistance in
connection with the assumption by Xoma or a third party of Pfizer's obligations
and duties hereunder.

11.03 If either Pfizer or Xoma materially breaches or defaults in the
performance or observance of any of the provisions of this Agreement, and such
breach or default is not cured within ninety (90) days after the giving of
notice by the other party specifying such breach or default, the other party
shall have the right to terminate this Agreement in full upon a further thirty
(30) days' notice.

12.  MISCELLANEOUS

12.01 Force Majeure. No party shall be liable for failure of or delay in
performing obligations set forth in this Agreement, and no party shall be deemed
in breach of its obligations, if such failure or delay is due to natural
disasters or any causes reasonably beyond the control of such party.

<PAGE>
                                      -6-


12.02 Assignability. The Agreement may not be assigned by either party without
the prior consent of the other party; provided, however, (a) either party may
assign this Agreement to any entity which acquires substantially all of its
assets and business, and (b) Pfizer may assign this Agreement, in whole or in
part, to any Affiliate of Pfizer.

12.03 Pfizer Status. For the purpose of carrying out this Agreeement, Pfizer
shall act as an independent contractor and not as partner, joint venturer, or
agent and shall not bind nor attempt to bind Xoma to any contract.

12.04 Notices. Any notice, consent or approval required under this Agreement
shall be in writing sent by registered or certified mail, postage prepaid, or by
telex or telecopier (confirmed by such registered or certified mail) and
addressed as follows:

If to Pfizer:                               If to Xoma:

Pfizer Inc                                  Xoma Corporation
235 East 42nd Street                        2910 Seventh Street
New York, New York                          Berkeley, California
10017                                       94710
Attn:  General Counsel                      Attn:  General Counsel
Telex:  856-697                             Telex:  420440
Telecopier No.:  (212) 573-1445             Telecopier No.:  (415) 644-2011

All notices shall be deemed to be effective on the date of mailing. In case any
party changes its address at which notice is to be received, written notice of
such change shall be given without delay to the other party.

12.05 Entire Agreement. This Agreement sets forth the entire agreement and
understanding among the parties hereto as to the subject matter hereof and has
priority over all documents, verbal consents or understandings made between
Pfizer and Xoma before the conclusion of this Agreement with respect to the
subject matter hereof; none of the terms of this Agreement shall be amended or
modified except in writing signed by the parties hereto.

12.06 Waivers. A waiver by any party of any term or condition of this Agreement
in any one instance shall not be deemed or construed to be a waiver of such term
or condition for any similar instance in the future or of any subsequent breach
hereof.

12.07 Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California without regard to the
conflicts of laws provisions thereof.

<PAGE>
                                       -7-


12.08 Remedies. The rights and remedies of a party set forth herein with respect
to failure of the other to comply with the terms of this Agreement (including,
without limitation, rights of full or partial termination of this Agreement) are
not exclusive, the exercise thereof shall not constitute an election of remedies
and the aggrieved party shall in all events be entitled to seek whatever
additional remedies may be available in law or in equity.

12.09 Headings and Sections. Headings in this Agreement are included herein for
ease of reference only and shall have no legal effect. References to sections
are to sections of this Agreement, unless otherwise specified.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first written above by their duly authorized officers.

                                  XOMA CORPORATION


                                  By /s/  C.L. Dellio
                                     Clarence L. Dellio,
                                     Senior Vice President, Operations

                                  PFIZER INC


                                  By /s/  John Mitchell
                                     Vice President

<PAGE>
                                       -8-

                             SCHEDULE OF ATTACHMENTS



Attachment 1                                Definitions

Attachment 8.01                             Pfizer In-Process Labels

Attachment 8.02                             Xoma Shipping Labels

<PAGE>

                                       -9-


                                  ATTACHMENT 1

                                   DEFINITIONS

1.   "Affiliate" means (a) any company owned or controlled to the extent of at
     least fifty percent (50%) of its issued and voting capital by a party to
     this Agreement and any other company so owned or controlled (directly or
     indirectly) by any such company or the owner of any such company, or (b)
     any partnership, joint venture or other entity directly or indirectly
     controlled by, controlling, or under common control of, to the extent of
     fifty percent (50%) or more of voting power (or otherwise having power to
     control its general activities), a party to this Agreement, but in each
     case only for so long as such ownership or control shall continue.

2. "CBER" means FDA's Center for Biologics Evaluation and Research.

3. "E5" means the antibody drug substance that is the subject of the PLA.

4.   "FDA" means the U.S. Food and Drug Administration.

5.   "GMP" means current good manufacturing practices, as specified in
     regulations promulgated from time to time by the FDA.

6.   "PLA" means the application for a product license submitted by Xoma to the
     FDA for E5 on or about March 31, 1989 and assigned reference number
     89-0246, as amended from time to time.

<PAGE>
                                      -10-


                                 ATTACHMENT 8.01

                            PFIZER IN-PROCESS LABELS

1.       Label for bulk drug container
         (Image of label with the following data inserted here)

         E5 ANTIBODY
         LOT NUMBER                 ITEM CODE
         (BAR CODE)                 (BAR CODE)
         R00000                     97205
         QUANTITY                   UM
         (BAR CODE)                 (BAR CODE)
         TBD                        GM
         HAZARD WARNING INFORMATION
         NONE
         See MSDS for Full Information

2.       Label for in-process filled vials

         E - 5 ANTIBODY 2 MG/ML 10 ML FILL LOT # 00000A QC 721


<PAGE>

                                      -11-



                                 ATTACHMENT 8.02

                              XOMA SHIPPING LABELS



(Image of label with the following information inserted here)


         E5(R) DRUG SUBSTANCE    XOMA
         Volume:           Liters
         2 mg/mL Monoclonal Antiendotoxin Antibody in 5 mM Sodium Phosphate/0.15
         M Sodium Chloride Buffer, pH 7.3 containing 0.01% Polysorbate 80
         CAUTION: NEW DRUG -- LIMITED BY FEDERAL LAW TO INVESTIGATIONAL USE FOR
         FURTHER MANUFACTURING PROCESSING OR REPACKING ONLY. XOMA Corporation
         Store at -10(degree)C to -20(degree)C Berkeley, CA 94710 P/N 101390
         Lot: XXXXXXX Label 101554E




[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission.


                              SETTLEMENT AGREEMENT

     This Settlement Agreement ("Agreement"), effective as of the 28th day of
July, 1992, is made and entered into by and among Centocor, Inc., a Pennsylvania
corporation having offices at 200 Great Valley Parkway, Malvern, Pennsylvania
19355 ("Centocor"); Pfizer Inc, a Delaware corporation having offices at 235
East 42nd Street, New York, New York 10017 ("Pfizer"); The Regents of the
University of California, a California corporation having offices at 300
Lakeside Drive, 22nd Floor, Oakland, California 94612 ("University"); Velos
Group, a Maryland partnership having a business address of 4824 Montgomery Lane,
Bethesda, Maryland 20814 ("Velos"); and Xoma Corporation, a Delaware corporation
having offices at 2910 Seventh Street, Berkeley, California 94710 ("Xoma").

                                    RECITALS

     WHEREAS, Centocor has developed a product for treating bacterial infections
comprised of the HA-1A monoclonal antibody ("HA-1A Product") which (i) is the
subject of a product license application pending before the United States Food
and Drug Administration ("FDA"), and (ii) has been approved for sale by
governmental authorities in certain European countries; and

                                        1
<PAGE>

     WHEREAS, Xoma has developed a product for treating bacterial infections
comprised of the E5 monoclonal antibody ("E5 Product") which is the subject of
product license applications pending before (i) the FDA and (ii) the Committee
for Proprietary Medicinal Products ("CPMP") and other governmental authorities;
and

     WHEREAS, Centocor is the owner by assignment of (i) U.S. Patent Application
Serial No. 542,111 filed October 14, 1983, and all divisionals, continuations,
continuations-in-part, reissues, reexaminations and extensions thereof; and (ii)
any patent applications or patents that have issued or may issue under the law
of any jurisdiction other than the United States that are counterparts of or
that, in whole or in part, claim or are entitled to claim priority directly or
indirectly from U.S. Patent Application Serial No. 542,111 and all divisionals,
continuations, continuations-in-part, reissues, reexaminations, and extensions
thereof (collectively, "Centocor Patent Rights"); and

     WHEREAS, Centocor is the owner by assignment of (i) U.S. Patent Application
Serial  No.  304,884  filed  February  1,  1989,  (ii) U.S.  Letters  Patent No.
5,057,598  entitled  "Monoclonal  Antibodies  Reactive with Endotoxin  Core" and
(iii)  U.S.  Patent  Application  Serial No.  492,374  filed May 6, 1983 and all
divisionals, continuations, continuations-in-part,  reissues, reexaminations and
extensions thereof (collectively, "U.S. Velos Patent Rights"); and

                                        2
<PAGE>

     WHEREAS,  Velos is the  owner by  assignment  of  patent  applications  and
patents  that have issued or may issue under the law of any  jurisdiction  other
than the United  States that are  counterparts  of or that, in whole or in part,
claim or are entitled to claim priority  directly or indirectly from U.S. Patent
Applications  Serial  Nos.  492,374  and  304,884  and U.S.  Letters  Patent No.
5,057,598, and all divisionals, continuations, continuations-in-part,  reissues,
reexaminations  and extensions  thereof  (collectively,  "Non-U.S.  Velos Patent
Rights"),  and  Centocor is the  exclusive  licensee of  Non-U.S.  Velos  Patent
Rights; and

     WHEREAS,  University  is  the  owner  by  assignment  of  (i)  U.S.  Patent
Application  Serial No. 855,878 filed April 24, 1986 and U.S. Letters Patent No.
4,918,163 entitled  "Monoclonal  Antibodies Specific for Lipid A Determinants on
Gram Negative  Bacteria" issuing thereon and U.S. Patent  Application Serial No.
781,242 filed September 27, 1985 and U.S. Letters Patent No.  4,777,136  issuing
thereon and all  divisionals,  continuations,  continuations-in-part,  reissues,
reexaminations  and  extensions  thereof;  and (ii) any patent  applications  or
patents  that have issued or may issue under the law of any  jurisdiction  other
than the United  States that are  counterparts  of or that, in whole or in part,
claim or are entitled to claim priority  directly or indirectly from U.S. Patent
Applications  Serial  Nos.  781,242 and  855,878  and U.S.  Letters  Patent Nos.
4,918,163    and    4,777,136,     and    all    divisionals,     continuations,
continuations-in-part, reissues,

                                        3
<PAGE>

reexaminations and extensions thereof (collectively, "University Patent
Rights"), and XOMA is the exclusive licensee of University Patent Rights; and

     WHEREAS, certain of the parties hereto are involved in litigation and other
proceedings concerning,  inter alia, (a) claims of infringement by HA-1A Product
of U.S. Letters Patent No. 4,918,163 in Civil Action No.  C-90-1129-RHS  pending
in the United  States  District  Court for the Northern  District of  California
captioned Xoma Corporation v. Centocor,  Inc. (the "California Action") in which
Centocor has filed a notice of appeal to the United  States Court of Appeals for
the Federal  Circuit,  No.  92-1267  (the  "Appeal")  and in  Investigation  No.
337-TA-323,  pending under suspension in the United States  International  Trade
Commission  captioned  In  the  Matter  of  Certain  Monoclonal  Antibodies  for
Therapeutically Treating Humans Having Gram Negative Bacterial Infections,  (the
"ITC Proceeding");  and (b) claims of infringement by E5 Product of U.S. Letters
Patent No.  5,057,598  in Civil  Action No. C 92-95 (LON)  pending in the United
States District Court for the District of Delaware captioned  Centocor,  Inc. v.
Xoma Corporation and Pfizer Inc (the "Delaware Action"); and

     WHEREAS, the parties do not intend by this Agreement to affect in any way
the rights and obligations, if any, of University, the Board of Trustees of the
Leland Stanford Junior University ("Stanford") and Centocor under a license from
Stanford to Centocor of the right to make, use and/or sell HA-1A

                                        4
<PAGE>

Product ("Stanford/Centocor License"); and

     WHEREAS, in order to avoid the expense and inconvenience of continued
litigation and other proceedings, the parties hereto wish to compromise and
resolve their differences with respect to the above and other matters.

     NOW THEREFORE, in consideration of the promises and mutual covenants,
agreements and releases herein contained, the receipt and sufficiency of which
are hereby acknowledged, the parties agree as follows:

     1. Centocor and Velos Releases. Centocor and Velos, on behalf of themselves
and their affiliates, parents and subsidiaries and each of their respective
directors, officers, employees, partners, representatives, agents,
subcontractors, sublicensees, attorneys, heirs, executors, administrators,
successors and assigns and all others claiming under or through them (sometimes
hereinafter referred to as "Centocor/Velos Releasors" and sometimes hereinafter
referred to as "Centocor/Velos Releasees") hereby release and discharge (i) Xoma
and Pfizer and their affiliates, parents and subsidiaries and each of their
respective directors, officers, employees, partners, representatives, agents,
subcontractors, sublicensees, attorneys, heirs, executors, administrators,
successors and assigns (sometimes hereinafter referred to as "Xoma/Pfizer
Releasees" and sometimes hereinafter referred to as "Xoma/Pfizer Releasors") of
and from all manner of actions, causes of action,

                                        5

<PAGE>


suits, debts, dues, sums of money, accounts, reckonings, bonds, bills,
specialties, covenants, contracts, controversies, agreements, promises,
variances, trespasses, damages, judgments, extents, executions, claims and
demands whatsoever, in law, in admiralty or in equity, whether known or unknown,
which Centocor/Velos Releasors or any of them ever had, now have or may have
for, upon or by reason of any matter, cause or thing whatsoever from the
beginning of the world to the effective date of this Agreement against
Xoma/Pfizer Releasees, or any of them, and (ii) University and its affiliates,
parents and subsidiaries and each of their respective directors, officers,
employees, partners, representatives, agents, subcontractors, sublicensees,
attorneys, heirs, executors, administrators, successors and assigns (sometimes
hereinafter referred to as "University Releasees" and sometimes hereinafter
referred to as "University Releasors") of and from all manner of actions, causes
of action, suits, debts, dues, sums of money, accounts, reckonings, bonds,
bills, specialties, covenants, contracts, controversies, agreements, promises,
variances, trespasses, damages, judgments, extents, executions, claims and
demands whatsoever, in law, in admiralty or in equity, whether known or unknown,
which Centocor/Velos Releasors or any of them ever had, now have or may have
for, upon or by reason of any matter, cause or thing whatsoever related to the
infringement of Centocor Patent Rights, U.S. Velos Patent Rights and/or Non-U.S.
Velos Patent Rights from the beginning of the world to the effective date of
this

                                        6

<PAGE>


Agreement against University Releasees, or any of them.

Centocor and Velos Covenants Not To Sue. Centocor/Velos Releasors covenant that
they will not hereafter cause or assist in the assertion, instigation,
maintenance or pursuit of any claim for infringement, contributory infringement
or inducement of infringement of any patent now or hereafter owned, licensed,
acquired or otherwise controlled by Centocor/Velos Releasors against Xoma/Pfizer
Releasees and/or University Releasees, or any of them, or their distributors or
customers or any health care professionals, for the making, using or selling of
the E5 Product. In addition, Centocor and Velos on behalf of themselves and
their respective parents and subsidiaries and each of their respective
directors, officers, employees, agents, attorneys and distributors (sometimes
hereinafter referred to as "Centocor/Velos Developers"), covenant that they will
not hereafter cause or assist in the assertion, instigation, maintenance or
pursuit of any claim for infringement, contributory infringement or inducement
of infringement of Centocor Patent Rights, U.S. Velos Patent Rights and/or
Non-U.S. Velos Patent Rights against [*] [*] and each of their respective
directors, officers, employees, agents, attorneys and distributors (sometimes
hereinafter referred to as [*]), or any of them, or their customers or any
health care professionals, for the making, using or selling of [*]

                                        7

<PAGE>


[*]. Also, Centocor/Velos Releasors covenant that they will not hereafter cause
or assist in the assertion, instigation, maintenance or pursuit of any claim
against Xoma/Pfizer Releasees or University Releasees, or any of them, related
to the assertion of University Patent Rights in the California Action and the
existence of the Stanford/Centocor License.

     3. Xoma, Pfizer and University Releases. (i) Xoma/Pfizer Releasors hereby
release and discharge Centocor/Velos Releasees of and from all manner of
actions, causes of action, suits, debts, dues, sums of money, accounts,
reckonings, bonds, bills, specialties, covenants, contracts, controversies,
agreements, promises, variances, trespasses, damages, judgments, extents,
executions, claims and demands whatsoever, in law, in admiralty or in equity,
whether known or unknown, which Xoma/Pfizer Releasors or any of them ever had,
now have or may have for, upon or by reason of any matter, cause or thing
whatsoever from the beginning of the world to the effective date of this
Agreement against Centocor/Velos Releases or any of them, and (ii) University
Releasors hereby release and discharge Centocor/Velos Releasees of and from all
manner of actions, causes of action, suits, debts, dues, sums of money,
accounts, reckonings, bonds, bills, specialties, covenants, contracts,
controversies, agreements, promises, variances, trespasses, damages, judgments,
extents, executions,

                                        8

<PAGE>


claims and demands whatsoever, in law, in admiralty or in equity, whether known
or unknown, which University Releasors or any of them ever had, now have or may
have for, upon or by reason of any matter, cause or thing whatsoever related to
the infringement of University Patent Rights from the beginning of the world to
the effective date of this Agreement, against Centocor/Velos Releasees or any of
them.

     4. Xoma, Pfizer and University Covenants Not To Sue. Xoma/Pfizer Releasors
and University Releasors covenant that they will not hereafter cause or assist
in the assertion, instigation, maintenance or pursuit of any claim for
infringement, contributory infringement or inducement of infringement of any
patent now owned, licensed or otherwise controlled by Xoma/Pfizer Releasors
and/or University Releasors (or, in the case of Xoma/Pfizer Releasors only,
hereafter owned, licensed, acquired or otherwise controlled) against
Centocor/Velos Releasees, or any of them, or their distributors or customers or
any health care professionals, for the making, using or selling of the HA-1A
Product, except that in the case of University Releasors, this covenant not to
sue is limited to patent rights administered by The Office of Technology
Transfer, Manager, Licensing, Biotechnology of the University ("OTT"). In
addition, [*] covenant that they will not hereafter cause or assist in the
assertion, instigation, maintenance or pursuit of any claim for infringement,
contributory infringement or inducement of

                                        9
<PAGE>

infringement of University Patent Rights against [*]
[*], or any of them, or their customers or any health care professionals, for
the making, using or selling of any [*].

     5. The California Action. Promptly upon execution of this Agreement, Xoma
and Centocor shall (a) execute and file a stipulation in the form annexed hereto
as Exhibit A providing for the dismissal of the Appeal and (b) execute and file
a final judgment on consent in the California Action in the form annexed hereto
as Exhibit B.

     6. The Delaware Action. Promptly upon execution of this Agreement, Xoma,
Pfizer and Centocor shall execute and file a final judgment on consent in the
Delaware Action in the form annexed hereto as Exhibit C.

     7. The ITC Proceeding. Promptly upon execution of this Agreement, Xoma and
Centocor shall execute and file a stipulation in the form annexed hereto as
Exhibit D providing for withdrawal of the complaint in, and termination of, the
ITC Proceeding.

     8. Further Consideration. From the date of FDA

                                       10

<PAGE>


approval of the product license application for the HA-1A Product [*] ("Centocor
HA-1A Product Royalty Term"), Centocor shall pay to Xoma royalties of [*] of all
Net Sales of HA-1A Product in the United States. [*] [*]

     The term "Net Sales" shall mean the [*] [*] sold by Centocor during the
Centocor HA-1A Product Royalty Term or the Centocor [*] Royalty Term, as the
case may be, to any [*] less the sum of deductions actually applicable to such
sales for: (a) discounts and allowances; (b) credits for rejected, damaged and
returned goods; (c) transportation charges; and (d) tariffs, import/export
duties, excise taxes, value added taxes, sales and use taxes and other similar
governmental charges

                                       11

<PAGE>


paid in connection with any such sales (collectively, "Deductions"). Net Sales
of HA-1A Product or any Non-HA-1A Product shall not include sales of HA-1A
Product or any Non-HA-1A Product by Centocor to [*], but shall include the [*],
less Deductions, for HA-1A Product [*] during the Centocor HA-1A Product Royalty
Term or the Centocor Non-HA-1A Product Royalty Term, as the case may be, to [*].

     Within 90 days following the end of each calendar quarter during the
Centocor HA-1A Product Royalty Term and/or Centocor Non-HA-1A Product Royalty
Term in which Net Sales of HA-1A Product or any Non-HA-1A Product are made,
Centocor shall provide to Xoma a written report setting forth the total Net
Sales of HA-1A Product and/or any Non-HA-1A Product made during that quarter and
the aggregate fee due and payable to Xoma for such quarter, and with such report
Centocor shall remit to Xoma the amount of royalty payment shown thereby to be
due. If no Net Sales of HA-1A Product or any Non-HA-1A Product are made during
any such quarterly reporting period, a statement to that effect shall be made.

     Centocor shall keep complete and accurate books and records for the latest
three (3) years during the Centocor HA-1A Product Royalty Term and/or the
Centocor Non-HA-1A Product Royalty Term showing the Net Sales of HA-1A Product
and any Non-

                                       12

<PAGE>


HA-1A Product. Such records shall be in sufficient detail to enable the
royalties payable hereunder by Centocor to be determined. Centocor shall permit
the books and records referred to in this paragraph to be examined by Arthur
Andersen & Co., but not more than twice in any calendar year. Any such
examinations shall be at the expense of Xoma and conducted during reasonable
business hours of Centocor and upon reasonable notice to Centocor. The purpose
of any such examination shall be solely for verifying the amount of Net Sales of
HA-1A Product and/or any Non-HA-1A Product and the royalties payable as provided
for in this Agreement, and Arthur Andersen & Co. shall keep such information in
strict confidence, except as legally required in the judgment of counsel to
Arthur Andersen & Co., and disclose to Xoma only Net Sales of HA-1A Product and
any Non-HA-1A Product and royalties due and payable thereon.

     In the event any royalties payable under this Article 8 are not received by
Xoma when due, Centocor shall pay to Xoma interest charges on the total
royalties due but unpaid at the rate of [*] per annum or the highest rate
permitted by law (whichever is lower). In the event that any examination of
Centocor's records by Arthur Andersen & Co. under this Article 8 discloses that
the amount of the royalties paid for any quarterly reporting period was more
than [*] less than the amount finally determined to be due, Centocor shall pay
Xoma the reasonable cost of such examination.

     [*]

                                       13

<PAGE>


[*]

     9. Other Proceedings. No party to this Agreement shall commence or
voluntarily participate in any suit or proceeding (including, without
limitation, any patent opposition or reexamination proceeding), or otherwise
assert any claim challenging or denying the validity of any claim contained in
any University Patent Rights, Centocor Patent Rights, U.S. Velos

                                       14

<PAGE>


Patent Rights and/or Non-U.S. Velos Patent Rights; except that nothing in this
Agreement shall prevent Pfizer from challenging or denying the validity of any
claims contained in any Centocor Patent Rights, U.S. Velos Patent Rights and/or
Non-U.S. Velos Patent Rights (sometimes hereinafter referred to as
"Centocor/Velos Patent Rights") in response to any claims against Pfizer for
infringement, contributory infringement or inducement of infringement of
Centocor/Velos Patent Rights. Immediately after the effective date of this
Agreement, Xoma and Pfizer shall cease to participate in any proceeding with
respect to any and all oppositions filed against European Patent No. 0 151 128;
provided that such conduct shall not constitute evidence that Pfizer
acknowledges the validity of said European Patent in any proceeding charging
Pfizer with infringement of said European Patent. No party to this Agreement
shall voluntarily make any statement which is slanderous, libelous or otherwise
defamatory of any other party hereto or its employees.

     10. Representations and Warranties.

     (a) Centocor and Velos represent and warrant that the making, having made,
using and selling of E5 Product does not infringe any patents or patent
applications owned by or licensed to Centocor or Velos as of the date hereof
except for Centocor Patent Rights, U.S. Velos Patent Rights and Non-U.S. Velos
Patent Rights.

     (b) Xoma, Pfizer and University represent and warrant

                                       15

<PAGE>


that the making, having made, using and selling of HA-1A Product does not
infringe any patents or patent applications owned by or licensed to Xoma, Pfizer
or University (in University's case, administered by the OTT) as of the date
hereof except for University Patent Rights.

     (c) Each party to this Agreement represents and warrants that (i) it has
full right and authority to enter into this Agreement and to perform its
obligations hereunder without consent or approval of any third person; and (ii)
that it is not subject to any restriction which would impair its rights and
obligations under this Agreement. Each party further represents and warrants
that it has taken all action required to authorize it to enter into this
Agreement and to render it binding upon it.

     (d) Centocor and Velos shall indemnify and hold harmless Xoma, Pfizer and
University from any loss, cost, expense or expenditure (including reasonable
attorneys' fees) suffered or incurred by Xoma, Pfizer or University in
connection with any breach by Centocor or Velos of the release(s) set forth in
Article 1 hereof or the covenants not to sue set forth in Article 2 hereof.

     (e) Xoma, Pfizer and University (and in the University's case, only for the
direct release herein by the University) shall indemnify and hold harmless
Centocor and Velos from any loss, cost, expense or expenditure (including
reasonable attorneys' fees) suffered or incurred by Centocor or Velos in
connection with any breach by Xoma, Pfizer or University of the

                                       16

<PAGE>


release(s) set forth in Article 3 hereof or the covenants not to sue set forth
in Article 4 hereof.

     11. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which shall
be deemed to be and constitute one and the same instrument; and in making proof
of this Agreement it shall not be necessary to produce or account for more than
one such fully executed Agreement.

     12. No Prior Assignment. The parties (in the case of University, the OTT)
hereto, and each of them, hereby represent and warrant that none of them has
assigned or transferred, in whole or in part, any claim, right, demand or cause
of action which it may now have or may have had or claim to have, of whatever
kind or nature, against any other party hereto, or any of the directors,
officers, employees, partners, affiliates, parents, subsidiaries,
representatives, agents or attorneys of such party, either in their
representative or in their individual capacities, to any other person,
corporation or other entity in any manner, including but not limited to
assignment or transfer by subrogation or by operation of law. In the event that
any party shall have assigned or transferred, or purported to assign or to
transfer, any claim or other matter herein released, such party shall indemnify,
defend and hold harmless each other party from and against any loss, cost, claim
or expense (including but

                                       17

<PAGE>


not limited to all costs related to the defense of any action, including
reasonable attorneys' fees) based upon, arising out of or occurring as a result
of any such claim, assignment or transfer.

     13. Assignment. This Agreement shall not be assignable by any party without
the prior written consent of each of the other parties which consents shall not
be unreasonably withheld. Xoma covenants that it will not sell or otherwise
transfer its business relating to the E5 Product and/or University Patent Rights
(or the right to sue thereunder) without requiring the transferee(s) to assume
in writing all of the obligations of Xoma under this Agreement. Centocor
covenants that it will not sell or otherwise transfer its business relating to
the HA-1A Product and/or Centocor Patent Rights, U.S. Velos Patent Rights and/or
Non-U.S. Velos Patent Rights (or the right to sue thereunder) without requiring
the transferee(s) to assume in writing all of the obligations of Centocor under
this Agreement.

     Xoma and/or University shall record, and request the United States Patent
and Trademark Office and each foreign patent office in which University Patent
Rights are pending or have issued, to file with each patent or patent
application included in University Patent Rights, a statement that each such
patent or patent application is subject to an agreement which transfers rights
thereunder to Centocor and Velos and which provides that

                                       18

<PAGE>


such patents or patent applications may not be further assigned or licensed
hereunder unless any such assignee or licensee agrees to accept Xoma's
obligations hereunder. Centocor and Velos shall record, and request the United
States Patent and Trademark Office and each foreign patent office in which
Centocor Patent Rights, U.S. Velos Patent Rights and/or Non-U.S. Velos Patent
Rights are pending or have issued, to file with each patent or patent
application included in Centocor Patent Rights, U.S. Velos Patent Rights and/or
Non-U.S. Velos Patent Rights a statement that each such patent or patent
application is subject to an agreement which transfers rights thereunder to
Xoma, Pfizer and University and which provides that such patents or patent
applications may not be further assigned or licensed hereunder unless any such
assignee or licensee agrees to accept Centocor's obligations hereunder (and in
the case of Non-U.S. Velos Patent Rights any such assignee or licensee agrees to
accept Velos' obligations hereunder).

     14. Stanford/Velos/Centocor Licenses. Anything herein to the contrary
notwithstanding, nothing in this Agreement is intended, nor shall be deemed, to
affect or modify in any way the rights and obligations, if any, of University,
Stanford, Velos and Centocor under the Stanford/Centocor License or the
Velos/Centocor License dated June 25, 1987 as amended.

     15. Execution of Agreement. This Agreement may be amended, modified or
otherwise changed only in a writing signed by all parties hereto. Each party
further represents and warrants that, except as set forth in this Agreement, it
has not

                                       19

<PAGE>


relied upon or been induced by any representation, statement or disclosure of
any other party but has relied upon its own knowledge and judgment and upon the
advice and representation of counsel of its own selection in entering into this
Agreement, that it has read and fully understands the terms of this Agreement
and is fully advised as to the legal effect thereof.

     16. Confidentiality. The parties agree that all terms of this Agreement
shall be kept confidential and shall not be disclosed to anyone other than the
parties' directors, officers, employees, partners, accountants, insurers and
attorneys, except as legally required in the judgment of counsel to the parties,
provided that Centocor and Xoma will issue the press release attached hereto as
Exhibit E at 8:00 A.M. Eastern Standard Time on the first business day following
the effective date of this Agreement. Xoma, University and Pfizer shall maintain
information received from Centocor pursuant to this Agreement in strict
confidence and shall use the same only for the purpose of confirming the
royalties due hereunder.

     17. Remedies For Breach. The parties acknowledge that their remedy at law
for breach of this Agreement may not be adequate and, therefore, each of the
parties agrees that any party shall be entitled to the equitable remedy of
specific performance in the event of a breach or threatened breach by any other
party, without any bond or other security being required.

                                       20

<PAGE>


     18. Severability. If any one or more of the provisions of this Agreement
shall, for any reason, be held invalid, illegal or unenforceable in any respect,
such invalidity, illegality or unenforceability shall not affect any other
provision hereof, but this Agreement shall be construed as if such invalid,
illegal or unenforceable provisions had never been contained herein.

     19. Further Assurances. Each of the parties hereto shall take or cause to
be taken all such further actions to execute, deliver and file or cause to be
executed, delivered and filed such further documents and instruments, and to use
reasonable best efforts to obtain such consents, as may be necessary or as may
be reasonably requested in order to fully effectuate the purposes, terms and
conditions of this Agreement.

     20. Notices. All reports, notices and other communications hereunder shall
be in writing and shall be sent by registered mail or overnight courier to the
address of the party as set forth below:

                  For Centocor:             Centocor, Inc.
                                            200 Great Valley Parkway
                                            Malvern, Pennsylvania  19355
                                            Attention:  General Counsel

                  For Pfizer:               Pfizer Inc
                                            235 East 42nd Street
                                            New York, New York  10017
                                            Attention:  General Counsel

                  For University:           The Regents of the
                                            University of California

                                       21

<PAGE>


                                            300 Lakeside Drive, 22nd Floor
                                            Oakland, California  94612
                                            Attention:  General Counsel

                  For Velos:                Velos Group
                                            4824 Montgomery Lane
                                            Bethesda, Maryland  20814
                                            Attention:  General Counsel

                  For Xoma:                 Xoma Corporation
                                            2910 Seventh Street
                                            Berkeley, California  94710
                                            Attention:  General Counsel

     21. Parties To Bear Own Costs and Attorneys' Fees. Each of the parties
hereto shall bear its own costs, expenses and attorneys' fees, whether taxable
or otherwise, incurred in, or arising out of or connected with the Delaware
Action, the California Action, the Appeal and the ITC Proceeding.

     22. Governing Law. This Agreement shall be governed by and construed in
accordance with the internal laws of the State of New York without regard to
conflicts of law provisions; provided that each of the parties hereby
acknowledges and agrees that all claims under Section 1542 of the California
Civil Code and any other provision of law now or hereafter enacted, adjudicated
or sought to be adjudicated relating to the release or waiver of unknown or
unspecified claims are hereby specifically and expressly released and waived.
Each of the parties understands that Section 1542 of the California Civil Code
provides that "[a] general release does not extend to claims which the creditor
does not know or suspect to exist in his favor

                                       22

<PAGE>


at the time of executing the release, which if known by him must have materially
affected his settlement with the debtor." For purposes of this Agreement, each
of the parties acknowledges and agrees that he, she or it may be considered to
be both a "creditor" and a "debtor" for all purposes and with respect to all
claims, he, she or it may not know or suspect to exist within the meaning of
Section 1542 of the California Civil Code and any other provision of law now or
hereafter enacted, adjudicated or sought to be adjudicated relating to the
release or waiver of unknown or unspecified claims.

     23. Binding Effect. This Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors, transferees and
assigns.

     24. No Implied Rights. Nothing contained in this Agreement shall be
construed to grant by implication, estoppel or otherwise any license or freedom
from suit under any patent or patent application other than University Patent
Rights, Centocor Patent Rights, U.S. Velos Patent Rights and Non-U.S. Velos
Patent Rights or any patent which would be infringed by the manufacture, use or
sale of HA-1A Product or E5 Product.

     25. Entire Agreement. With the exception of the license agreement between
Xoma and University related to

                                       23

<PAGE>


University Patent Rights, this Agreement, together with the exhibits hereto,
constitutes, on and as of the effective date hereof, the entire agreement of the
parties with respect to the subject matter hereof, and all prior or
contemporaneous understandings or agreements, whether written or oral, between
or among the parties with respect to such subject matter are hereby superseded
in their entireties.

                                       24
<PAGE>
     IN WITNESS WHEREOF, and intending to be bound thereby, the parties have
caused this Agreement to be executed by their duly authorized representatives on
the dates set forth below.

Dated:  7/23/92                     CENTOCOR, INC.

                                    By:  /s/ Hubert J.P. Shoemaker
                                             Hubert J.P. Shoemaker, Ph.D.
                                             Chairman of the Board and
Attest: /s/(unknown)                          Chief Executive Officer


Dated: 7/24/92                      PFIZER INC

                                    By:  /s/Peter C. Richardson
                                         Assistant Secretary
Attest: /s/(unknown)


Dated:  7/30/92                     THE REGENTS OF THE UNIVERSITY
                                      OF CALIFORNIA

                                    By:  /s/ John F. Lundberg
                                             John F. Lundberg
Attest: /s/(unknown)                         Deputy General Counsel


Dated:  7/23/92                     VELOS GROUP

                                    By:  /s/Arthur S. House

Attest: /s/(unknown)


Dated:  7/23/92                     XOMA CORPORATION

                                    By:  /s/ John L. Castello
                                             John L. Castello
                                             President and
Attest: /s/(unknown)                          Chief Executive Officer

                                       25


<PAGE>


                                                                       EXHIBIT A

                         UNITED STATES COURT OF APPEALS
                             FOR THE FEDERAL CIRCUIT

XOMA CORPORATION,
         Plaintiff - Appellee,                                No. 92-1267
         v.
CENTOCOR, INC., Defendant - Appellant.

                XOMA'S AND CENTOCOR'S JOINT MOTION FOR DISMISSAL

     Plaintiff-Appellee Xoma Corporation ("Xoma") and Defendant-Appellant
Centocor, Inc. ("Centocor") hereby jointly move for dismissal of the
above-identified appeal in accordance with Fed. R. App. Pro. 42(b), without
costs. A proposed ORDER is attached.

Dated:  New York, New York
        July    , 1992
                                      Respectfully submitted,
                                      (blank)
                                      Gerald Sobel
                                      KAYE, SCHOLER, FIERMAN,
                                         HAYS & HANDLER
                                      425 Park Avenue
                                      New York, New York  10022
                                      Attorneys for Plaintiff-Appellee,
                                        Xoma Corporation

                                  (blank line)
                                      Thomas H. Jenkins
                                      FINNEGAN, HENDERSON, FARABOW,
                                        GARRETT & DUNNER
                                      1300 I Street, N.W.
                                      Washington, D.C.  20005
                                      Attorneys for Defendant-Appellant,
                                        Centocor, Inc.


<PAGE>


                         UNITED STATES COURT OF APPEALS
                             FOR THE FEDERAL CIRCUIT

XOMA CORPORATION,
        Plaintiff-Appellee,
         v.                                                      No. 92-1267
CENTOCOR, INC.,
        Defedant-Appellant.

                               ORDER OF DISMISSAL

     The Court, pursuant to Fed. R. App. Pro. 42(b), having been advised by
counsel for the parties that the parties consent to entry of the following Order
of Dismissal:

     IT IS ORDERED, ADJUDGED AND DECREED:

         (1) This appeal is hereby dismissed; and (2) No costs or attorneys'
         fees are assessed or awarded.

Dated:  (blank), 1992                       (blank line)

                                        2


<PAGE>


                                                                       EXHIBIT B

                   IN THE UNITED STATES DISTRICT COURT FOR THE
                         NORTHERN DISTRICT OF CALIFORNIA

XOMA CORPORATION,
         Plaintiff,                                  C-90-1129 RHS
vs.
CENTOCOR, INC.,
         Defendant.

                            FINAL JUDGMENT ON CONSENT

     WHEREAS, plaintiff, Xoma Corporation ("Xoma"), a corporation organized and
existing under the laws of the State of Delaware with its primary place of
business in Berkeley, California, has filed suit against defendant, Centocor,
Inc. ("Centocor"), a corporation organized and existing under the laws of the
Commonwealth of Pennsylvania having its principal place of business in Malvern,
Pennsylvania, in Civil Action No. C-90-1129-RHS;

     WHEREAS, Centocor counterclaimed against Xoma in said Civil Action;

     WHEREAS, said Civil Action was tried to a jury and the jury returned a
verdict on or about October 26, 1991 that United States Patent No. 4,918,163 is
valid and is infringed both literally and under the doctrine of equivalents by
Centocor's manufacturing and distributing the monoclonal antibody known as

<PAGE>
HA-1A (trade name CENTOXIN) for the treatment of gram negative infections in
humans;

     WHEREAS, the jury also found that Centocor did not have an implied license
to make, use or sell HA-1A under United States Patent No. 4,918,163; and

     WHEREAS, Xoma and Centocor have consented to the entry of this judgment;

     There being no just reason for delay, and upon an express direction for the
entry of judgment, it is hereby ORDERED, ADJUDGED and DECREED as follows:

     1. United States Patent No. 4,918,163 is valid.

     2. United States Patent No. 4,918,163 has been infringed by CENTOCOR.

     3. Centocor does not have an implied license to United States Patent No.
4,918,163.

     4. Centocor shall pay to Xoma damages in the amount of $100,000.

     5. All other claims and all counterclaims are dismissed with prejudices.

     6. The Amended Order entered on January 14, 1992 is hereby superseded and
is of no further force or effect.

                                        2


<PAGE>


                                   SO ORDERED

Date: (blank)                          (blank line)
                                        United States District Judge

     Entry of the foregoing Order and Decree hereby is consented to:

                                       XOMA CORPORATION

Date: (blank)                          By (blank line)
                                           Name:
                                           Title:

                                       CENTOCOR, INC.

Date: (blank)                          By (blank line)
                                          Name:
                                          Title:

                                       KAYE, SCHOLER, FIERMAN,
                                         HAYS & HANDLER
                                       425 Park Avenue
                                       New York, New York  10022
                                       (212) 836-8000
                                       Attorneys for Plaintiff
                                       Xoma Corporation

Date: (blank)                          By (blank line)
                                       Gerald Sobel, Esq.

                                        3
<PAGE>
                                       FINNEGAN, HENDERSON, FARABOW,
                                         GARRETT & DUNNER
                                       1300 I Street, N.W.
                                       Washington, D.C.  20005
                                       Attorneys for Defendant
                                       Centocor, Inc.

Dated: (blank)                         By (blank line)
                                       Thomas H. Jenkins, Esq.

                                        4


<PAGE>


                                                                       EXHIBIT C

                       IN THE UNITED STATES DISTRICT COURT
                          FOR THE DISTRICT OF DELAWARE

CENTOCOR, INC.,
                  Plaintiff,
v.                                                 Civil Action No. 92-95
XOMA CORPORATION,
and PFIZER INC.,
                  Defendants.

                            FINAL JUDGMENT ON CONSENT

     WHEREAS, plaintiff, Centocor, Inc. ("Centocor"), a corporation organized
and existing under the laws of the Commonwealth of Pennsylvania having its
principal place of business in Malvern, Pennsylvania, has filed suit against
defendants, Xoma Corporation ("Xoma"), a corporation organized and existing
under the laws of the State of Delaware with its primary place of business in
Berkeley, California, and Pfizer Inc. ("Pfizer"), a corporation organized and
existing under the laws of the State of Delaware with its primary place of
business in New York, New York, in Civil Action No. 92-95; and

     WHEREAS, Xoma Pfizer counterclaimed against Centocor in said Civil Action;
and

     WHEREAS, Xoma, Centocor and Pfizer have consented to the entry of this
judgment;


<PAGE>


     There being no just reason for delay, and upon an express direction for the
entry of judgment, it is hereby ORDERED, ADJUDGED and DECREED as follows:

     (1) This action including all claims and all counterclaims is hereby
dismissed with prejudice; and

     (2) No costs or attorneys' fees are assessed or awarded.

                                   SO ORDERED

Date: (blank)                        (blank line)
                                     United States District Judge

     Entry of the foregoing Order and Decree hereby is consented to:

                                     XOMA CORPORATION

Date: (blank)                        By (blank line)
                                         Name:
                                         Title:

                                     CENTOCOR, INC.

Date: (blank)                        By (blank line)
                                        Name:
                                        Title:

                                        2


<PAGE>


                                     PFIZER INC.

Date: (blank)                        By (blank line)
                                        Name:
                                        Title:

                                     KAYE, SCHOLER, FIERMAN,
                                       HAYS & HANDLER
                                     425 Park Avenue
                                     New York, New York  10022
                                     (212) 836-8000
                                     Attorneys for Defendants
                                     Xoma Corporation and
                                     Pfizer Inc.

Date: (blank)                        By (blank line)
                                     Gerald Sobel, Esq.

                                    POTTER, ANDERSON & CARROON
                                    Delaware Trust Building
                                    P.O. Box 951 Wilmington,
                                    Delaware 19899 Attorneys
                                    for Plaintiff Centocor,
                                    Inc.

Dated: (blank)                      By (blank line)
                                    Robert K. Payson, Esq.

                                        3


<PAGE>


                                                                       EXHIBIT D
                  UNITED STATES INTERNATIONAL TRADE COMMISSION
                             Washington, D.C. 20436
                              Before Janet D. Saxon
                            Administrative Law Judge

IN THE MATTER OF
                               Inv. No. 337-TA-323
CERTAIN MONOCLONAL ANTIBODIES
USED FOR THERAPEUTICALLY
TREATING HUMANS HAVING GRAM NEGATIVE
BACTERIAL INFECTIONS

                XOMA'S AND CENTOCOR'S JOINT MOTION FOR DISMISSAL

     Petitioner Xoma Corporation ("Xoma") and Respondents Centocor, Inc.,
Centocor Partners II, L.P. and Centocor B.V. ("Centocor") jointly move for
dismissal of this proceeding without costs. A proposed ORDER is attached.

Dated:  New York, New York
        July    , 1992
                                  Respectfully submitted,

                                  (blank line)
                                  Gerald Sobel
                                  KAYE, SCHOLER, FIERMAN,
                                    HAYS & HANDLER
                                  425 Park Avenue
                                  New York, New York  10022
                                  Attorneys for Complainant

                                  (blank line)
                                  Tom M. Schaumberg
                                  ADDUCI, MASTRIANI, MEEKS
                                   AND SCHILL
                                  1140 Connecticut Avenue
                                  Washington, D.C.
                                  Attorneys for Respondents


<PAGE>


                  UNITED STATES INTERNATIONAL TRADE COMMISSION
                             Washington, D.C. 20436
                              Before Janet D. Saxon
                            Administrative Law Judge

IN THE MATTER OF
                               Inv. No. 337-TA-323
CERTAIN MONOCLONAL ANTIBODIES
USED FOR THERAPEUTICALLY
TREATING HUMANS HAVING GRAM NEGATIVE
BACTERIAL INFECTIONS

                               ORDER OF DISMISSAL

     Having been advised by counsel for the parties that the parties consent to
entry of the following Order of Dismissal:

         IT IS ORDERED, ADJUDGED AND DECREED:

         (1)  This proceeding is hereby dismissed; and

         (2) No costs or attorneys' fees are assessed or awarded.


Dated: (blank), 1992                                 (blank line)

                                        2


<PAGE>


                                    Exhibit E

Centocor and XOMA Announce Settlement of All Outstanding Litigation and Disputes

     Centocor, Inc. of Malvern, PA (NASDAQ: CNTO) and XOMA Corporation of
Berkeley, CA (NASDAQ: XOMA) announced today an agreement to settle all
outstanding litigation and disputes regarding each company's products, patents
and patent applications related to anti-endotoxin monoclonal antibodies.

     The agreement covers the XOMA v. Centocor litigation in the U.S. District
Court for the Northern District of California and pending appeals, a proceeding
initiated at the U.S. International Trade Commission, and the Centocor v. XOMA
lawsuit filed in the U.S. District Court for the District of Delaware.

     Centocor has agreed to pay royalties to XOMA for U.S. sales, if any, of its
monoclonal antibody HA-1A, and the companies have agreed to forego all future
litigation and adminstrative proceedings regarding each other's patents and
patent applications related to anti-endotoxin monoclonal antibodies.

     Centocor, Inc. is a biopharmaceutical company specializing in monoclonal
antibody technology.

     XOMA Corporation is a leading company in the development of therapeutic
products using monoclonal antibody and recombinant DNA technologies.


<PAGE>


News Release                                                         XOMA (logo)

                           For Release: July 29, 1992
                                      For Information Contact: Carol D. DeGuzman
                                                                  (510) 644-1170

XOMA AND CENTOCOR ANNOUNCE SETTLEMENT
OF ALL OUTSTANDING LITIGATION AND DISPUTES

     (Berkeley, CA, and Malvern, PA, July 29, 1992.) XOMA Corporation (NASDAQ:
XOMA) and Centocor, Inc. (NASDAQ: CNTO) announced today an agreement to settle
all outstanding litigation and disputes worldwide regarding each company's
products, patents and patent applications related to anti-endotoxin monoclonal
antibodies.

     The agreement covers the XOMA v. Centocor litigation in the U.S. District
Court for the Northern District of California and pending appeals, a proceeding
initiated at the U.S. International Trade Commission, and the Centocor v. XOMA
lawsuit filed in the U.S. District Court for the District of Delaware.

     Centocor has agreed to pay royalties for U.S. sales, if any, of its
monoclonal antibody HA-1A, and the companies have agreed to forego all future
litigation and administrative proceedings regarding each other's patents and
patent applications related to anti-endotoxin monoclonal antibodies.

     XOMA Corporation is a leading company in the development of therapeutic
products using monoclonal antibody and recombinant DNA technologies.







[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission

                                SUPPLY AGREEMENT
                       CHARLES RIVER BIOTECHNICAL SERVICES
                        FOR THE PRODUCTION OF ASCITES FOR
                                XOMA CORPORATION

                                                          AS OF DECEMBER 8, 1988
<PAGE>
THIS SUPPLY AGREEMENT ("Agreement") made as of this 8th day of December, 1988,
by and between CHARLES RIVER BIOTECHNICAL SERVICES, INC., a Delaware company
with its principal offices located at 251 Ballardvale Street, Wilmington,
Massachusetts 01887 ("CRBS") and XOMA CORPORATION, a Delaware company with its
principal offices located at 2910 Seventh Street, Berkeley, CA 94710 "XOMA".

                                     PURPOSE

XOMA desires to engage the facilities and services of CRBS for the production of
ascites (the "Product" or "Products") from the cell line owned by XOMA described
in the Statement of Work attached hereto as Exhibit A (the "Statement of Work"),
and CRBS desires to undertake such production, all according to the terms and
conditions set forth in this Agreement, the Statement of Work and a certain
Purchase Order hereinafter described.

Intending to be legally bound hereby, CRBS and XOMA hereby agree as follows:

1.0      TERM; SCOPE

         1.1 The effective date of this Agreement (the "Effective Date") shall
be February 27, 1989, such date being the date on which this Agreement, the
Statement of Work and the Purchase Order (as hereinafter described) are mutually
agreed to and accepted by XOMA and CRBS. The initial term of this Agreement
shall be for one (1) year from the Effective Date.

         1.2 The parties may extend the term of this Agreement for one or more
additional terms (an "Additional Term") by a written renewal agreement entered
into no later than the eight (8) month anniversary of the Effective Date,
revising the provisions hereof as they may agree for each Additional Term.

         1.3 This Agreement, including the Statement of Work and the Purchase
Order attached hereto and made a part hereof, covers the purchase by XOMA of
Products produced by CRBS during the Initial Term and any Additional Term. A
description of the Product is set forth in the Statement of Work.

2.0      PURCHASES; COMMITMENTS; PURCHASE ORDER

         2.1 XOMA shall be obligated to purchase a guaranteed amount of Products
during the Initial Term as specified in the Purchase Order and CRBS guarantees
it will produce and deliver the guaranteed amount (the "Guaranteed Amount"). In
addition, XOMA may in its discretion order additional Products in excess of the
Guaranteed Amount as provided in the Purchase Order by giving written notice to
CRBS of such increase at least one hundred

                                       -2-
<PAGE>
twenty (120) days prior to the requested delivery date for the additional
Products.

         2.2 XOMA shall initially order Products under the Agreement by issuing
to CRBS an initial purchase order (the "Purchase Order") which references this
Agreement, a copy of which is attached hereto as Exhibit B. The Purchase Order
shall contain the ordered amount, the Guaranteed Amount, estimated delivery
dates, definitive prices and any other specific terms agreed to by the parties.

3.0      PRICES; PAYMENT

         3.1 XOMA will pay a price for the Product as set forth in the Statement
of Work and the Purchase Order. Terms of the payment are One Hundred Percent
(100%) of the invoiced amount due net thirty (30) days from the later of the
date of invoice or the receipt of Product provided the shipped Product has been
tested and is acceptable. If XOMA gives notice to CRBS to retain an agreed upon
shipment of Product, then XOMA will pay for that shipment of Product within 30
days from the later of the date of invoice or the receipt of samples of Product,
provided the Product sample is found to be acceptable.

         3.2 The agreed upon prices for Product as set forth in the Purchase
Order includes the cost to CRBS of production, bulk product packaging, and
internal quality assurance activities as set forth in the Statement of Work. The
prices do not include sales, use, excise or any other similar taxes imposed by
Federal, state or local governments, and accordingly such taxes shall be paid by
XOMA.

         3.3 The prices for the Product shall be in accordance with the Pricing
Schedule attached hereto as Exhibit C.

                  3.3.1 Pricing will be adjusted retroactively in relation to
         the amount of Product ordered by XOMA and shipped by CRBS within a
         one-year term of the Agreement wherein the first one year begins with
         the initial shipment made under the Purchase Order issued December 13,
         1988.

                  3.3.2 The price for Product shall be reduced [*] percent [*]
         if XOMA finds after testing three or more successive lots or five lots
         cumulatively unacceptable due to failure of the Product to meet the
         specifications set forth in the Statement of Work. The price for
         Product shall also be reduced [*] percent [*] for each shipment which
         is not "timely" (as defined in Sections 4.2 and 7.0). This reduction in
         price shall apply only to the replacement(s) for each unacceptable lot
         and/or untimely Product shipment and shall not affect XOMA's right of
         termination set forth in Section 6.

                                       -3-
<PAGE>
                  3.3.3 XOMA shall pay CRBS a "bonus" of an additional [*]
         percent [*] over and above the price for Product where such Product is
         delivered by CRBS at the request of XOMA on advance notice of 60 days
         or less. This bonus shall apply only to each advance shipment.

         3.4 XOMA agrees to pay CRBS [*] percent [*] per month on any monies not
paid when due, or the legal maximum monthly rate; if lower, where the Products
are delivered.

4.0      DELIVERY; ACCEPTANCE

         4.1 Delivery shall be F.O.B. Raleigh, NC, with all freight and dry ice
expenses being prepaid by CRBS and added to CRBS's invoice to XOMA for payment
by XOMA. CRBS shall arrange insured common carrier transportation of the
Products to XOMA's specified plant or other designated destination. CRBS shall
arrange for adequate transportation insurance coverage for the replacement value
of the shipped Products. Title to and risk of loss of the Products shall pass to
XOMA at the time of delivery to XOMA. CRBS shall promptly following delivery
invoice XOMA for all Products tendered. Invoices shall be accompanied by the
commercial bills of lading.

         4.2 CRBS shall ship the Products in accordance with the Delivery
Schedule attached hereto as Exhibit D. For purposes of this Agreement, a timely
shipment shall be a shipment received by XOMA not later than two (2) weeks after
the agreed upon delivery date, subject to allowances for special delays set
forth in Section 7.

         4.3 XOMA shall give notice to CRBS as to the acceptance or rejection of
Product within thirty (30) days of receipt of Product or a representative
sample. The warranty on the Product under this Agreement shall survive such
acceptance.

5.0      WARRANTY; QUALITY ASSURANCE

         5.1 CRBS warrants that the Product is produced from XOMA's cell lines
as provided to CRBS and manufactured according to the Statement of Work. Upon
notification by XOMA that the Product is not acceptable, CRBS shall replace the
Product or remit to XOMA an amount equal to the price actually paid by XOMA to
CRBS for the unacceptable Product. Any modification of the Product by XOMA shall
void this warranty. The foregoing warranty shall be subject to XOMA maintaining
the Product in accordance with CRBS's instructions. THIS WARRANTY IS IN LIEU OF,
AND CRBS SPECIFICALLY DISCLAIMS AND EXCLUDES ALL OTHER WARRANTIES, EXPRESS,
IMPLIED OR STATUTORY, INCLUDING THE WARRANTIES OF MERCHANTABILITY, FITNESS

                                       -4-
<PAGE>
FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF A PATENT, TRADEMARK OR OTHER
INTELLECTUAL PROPERTY RIGHT. CRBS shall not, under any circumstances, be liable
for any special, indirect, consequential or incidental damages arising out of or
in connection with the Product.

         5.2 CRBS shall maintain a manufacturing and quality assurance program
that meets all applicable FDA/GMP requirements.

         5.3 CRBS agrees to notify XOMA within 48 hours of learning of the
failure of any batch of Products to meet the specifications set forth in
Statement of Work.

         5.4 XOMA shall have the right during normal business hours to audit
CRBS's facility for the purpose of observing production and quality control and
ensuring that CRBS's activities comply with FDA regulatory GMP requirements,
upon at least 24-hour advance notice. XOMA acknowledges that all information
learned from said audit, whether received in writing, orally or by observation,
is confidential and proprietary pursuant to a Secrecy Agreement between XOMA and
CRBS dated as of December 8, 1988 (the "Secrecy Agreement").

         5.5 In the event XOMA concludes following an audit pursuant to Section
5.4 that CRBS has been or is presently engaging in activities which reasonably
appear to XOMA to amount to a material violation of FDA/GMP requirements, then
CRBS shall either correct such violation or commence reasonable corrective
action pursuant to a corrective action plan deemed appropriate by XOMA within 30
days.

6.0      TERMINATION

         6.1 Either party shall have the right to terminate this Agreement
during the Initial Term or any Additional Term if:

                  6.1.1 the other party fails to remedy or to commence
reasonable corrective action to remedy any default in the performance of any
material condition or obligation under this Agreement within thirty (30) days of
written notice thereof, or

                  6.1.2 the other party files a petition in bankruptcy, or
enters into an arrangement with its creditors, or applies for and consents to
the appointment of a receiver or trustee, or makes an assignment for the benefit
of creditors, or suffers or permits the entry of an order adjudicating it to be
bankrupt or insolvent.

         6.2 The failure of either party to terminate this Agreement by reason
of the breach of any of its material provisions by the

                                       -5-

<PAGE>


other party shall not be construed as a waiver of the rights or remedies
available for any subsequent breach of the terms and provisions of this
Agreement.

7.0      FORCE MAJEURE

         7.1 Neither party shall be responsible for any failure to comply with
the terms of this Agreement, except for failure to make timely payments
hereunder, where such failure is due to force majeure, which shall include,
without limitation, fire, flood, explosion, strike, labor disputes, labor
shortages, picketing, lockout, transportation embargo or failures or delays in
transportation, strikes or labor disputes affecting supplies, or acts of God,
civil riot or insurrection, acts of the Federal Government or any agency
thereof, or judicial action. The time for performance where delay is excusable
hereunder shall be extended by a period of time equal to the time lost by reason
of the excused delay, provided that all reasonable efforts are taken by a party
to overcome the delay.

8.0      RECORDS INSPECTION; SAMPLE RETENTION

         8.1 All records relating to the manufacture of Products shall be
retained for a period of not less than five (5) years from the date of
manufacture of ascites or six (6) months from the expiration of the final
released Product, whichever is later. Prior to the destruction of any record,
written notice shall be provided to XOMA and XOMA shall have the right to
request and retain said record.

         8.2 CRBS shall retain repository samples for a period of not less than
two (2) years from the date of expiration of each batch of the Products. All
such samples shall be available for inspection and testing by XOMA upon
reasonable notice.

9.0      INDEMNITY

         9.1 XOMA will defend, at its own expense, any claim made or any suit or
proceeding brought against CRBS so far as it is based on the allegation that the
Product infringes a patent. XOMA will pay any costs, damages and attorney's fees
finally awarded against CRBS in such actions that are attributable to such
claim, provided that (a) CRBS promptly notifies XOMA in writing of such claim,
(b) CRBS gives XOMA such information and assistance as may be necessary to
defend or settle the claim and CRBS otherwise cooperates fully in such defense,
(c) XOMA is given the sole authority to defend or settle the claim at XOMA's
expense, (d) XOMA is afforded the opportunity to participate in the negotiation
of, and the right to approve or disapprove, any settlement of the claim, and (e)
CRBS complies with the terms of any court order or settlement entered with
respect to the claim.

                                       -6-

<PAGE>


In no event shall CRBS have any liability for any infringement of patents
resulting from (a) CRBS's compliance with XOMA's specifications or instructions,
or (b) XOMA's modification of the Product. The foregoing states the entire
liability of CRBS for patent infringement for the Product.

         9.2 XOMA hereby agrees to indemnify and hold harmless CRBS and its
officers and directors from and against any and all cost, damages, expenses and
attorney's fees incurred by CRBS as a result of any claims of third parties
based on or arising out of or based upon any acts or omissions, breach or
alleged breach of XOMA's agreements, obligations and warranties hereunder, and
CRBS hereby agrees to indemnify and hold harmless XOMA, and its officers and
directors from and against any and all cost, damages, expenses and attorneys'
fees incurred by XOMA as a result of any claims of third parties (other than
patent infringement claims as described in Section 9.1) based on or arising out
of or based upon any acts or omissions, breach or alleged breach of CRBS's
agreements, obligations and warranties hereunder.

10.0     TRADE NAMES AND TRADEMARKS

         10.1 XOMA hereby acknowledges that it does not have, and shall not
acquire, any interest in any of CRBS's trademarks or trade names appearing on
the labels or packaging materials for the Products unless otherwise expressly
agreed.

11.0     CONFIDENTIALITY

         11.1 The parties hereby acknowledge that any and all information,
knowledge, technology and trade secrets relating to the production, processing
and testing of Products are subject to the Secrecy Agreement and that the
obligations thereunder shall survive termination of this Agreement.

12.0     NOTICES

         12.1 Any and all notices permitted or required to be given hereunder
shall be sent by registered or certified mail, postage and fees paid, with
return receipt requested, addressed as follows:

         CRBS:

                  Charles River Biotechnical Services, Inc.
                  251 Ballardvale Street
                  Wilmington, Massachusetts 01887

                  Attention: James C. Foster
                                     President

                                       -7-

<PAGE>


         XOMA:

                  XOMA Corporation
                  2910 Seventh Street
                  Berkeley, CA 94710

                  Attention: Steven C. Mendell
                             Chairman and Chief Executive Officer

Notice shall be deemed given as of the date of mailing.

13.0     ASSIGNMENT

         13.1 Neither party shall assign this Agreement in whole or in part
without prior written consent of the other, except that no consent shall be
required to an assignment of this Agreement to a successor corporation in a
merger or acquisition. Once assigned, all of the provisions of this Agreement
and all rights and obligations of the parties hereunder shall be binding upon
and inure to the benefit of and be enforceable by the successors and assigns of
CRBS and XOMA.

14.0     ENTIRE AGREEMENT

         14.1 This Agreement, including the Statement of Work and the Purchase
Order, and the Secrecy Agreement, together constitute the entire Agreement
between the parties. Any and all amendments, or releases from any provisions
hereof and of the Statement of Work, Purchase Order and Secrecy Agreement must
be in writing, signed by both parties and specifically state that it is an
amendment or release.

15.0     INDEPENDENT CONTRACTOR

         15.1 In all activities under this Agreement, CRBS shall act as and be
deemed an independent contractor with no authorization to in any way obligate or
bind XOMA. This Agreement shall not be deemed held or construed as creating a
copartnership between XOMA and CRBS for any purpose whatsoever.

16.0     GOVERNING LAW

         16.1 The rights and obligations of the parties to this Agreement shall
be construed in the event of a dispute in accordance with the laws of the
Commonwealth of Massachusetts where CRBS is the defending party, and in
accordance with the laws of the State of California where XOMA is the defending
party.

                                       -8-

<PAGE>


17.0     SEVERABILITY

         17.1 If any term or provision of this Agreement shall be held invalid
or unenforceable, the remaining terms hereof shall not be affected, but shall be
valid and enforced to the fullest extent permitted by law.

18.0     HEADINGS

         18.1 The headings used in this Agreement are intended for guidance only
and shall not be considered part of the written understanding between the
parties hereto.

19.0     RIGHTS AND REMEDIES

         19.1 All rights and remedies, whether conferred hereby or by any other
instrument or by law shall be cumulative, any may be exercised singularly or
concurrently.

20.0     GOVERNMENT APPROVALS; EXPORT

         20.1 Each party represents and warrants to the other party that any and
all governmental approvals and/or licenses necessary for the satisfactory
performance of such party's obligations hereunder have been duly obtained.

         20.2 No United States Government Procurement Regulations shall be
binding on either party unless specifically agreed to in writing prior to
incorporation in this Agreement.

         20.3 XOMA acknowledges that the Product may be subject to certain
export controls, laws and regulations of the United States government, and
accordingly XOMA agrees not to export the Product outside the United States
without the prior consent of CRBS.

                      [Signature page immediately follows.]

                                       -9-

<PAGE>


IN WITNESS WHEREOF, XOMA and CRBS have caused this Agreement to be executed by
their duly authorized officers as of the day and year first above written.

                    CHARLES RIVER BIOTECHNICAL SERVICES, INC.

                     By:  /s/James C. Foster
                     James C. Foster
                     President

                     XOMA CORPORATION

                     By:  /s/Steven C. Mendell
                     Steven C. Mendell
                     Chairman and Chief Executive Officer

                                      -10-


<PAGE>


                                                                       Exhibit A

                              STATEMENT OF WORK TO
                  CHARLES RIVER BIOTECHNICAL SERVICES, INC. FOR
                      ASCITES PRODUCTION WITH [*] CELL LINE

1.   General

     Production procedures are to be performed in compliance with CGMP's.

2.   Cell Culture

     XOMA will supply a [*] cell line to be used [*] for each lot. The medium
     [*] described in the [*] production batch record number [*]. An inoculum of
     [*] will be prepared as described in production batch record [*].

     [*]

3.   Ascites Production

     All ascites collection from mice must be carried out in [*].

     [*]

     [*] Only [*] may be used. [*]

     [*] at least [*] prior to being used for production.

     [*]

     [*]

     [*]. Subsequent operations are performed following the procedure outlined
     in [*].

     [*]

     [*]

     [*]

4.   Testing and Specifications

     To be accepted by XOMA, the [*] ascites must meet the specifications
     described in the paragraphs below.

     [*]

     [*]

     [*]

                                        1


<PAGE>


                                                                       Exhibit A
                                                                          Page 2

         [*]
         [*]
         [*]
         [*]
         [*]
         [*]
         [*]
         [*]

5.   Shipment

     [*] ascites and samples are to be shipped to XOMA and other destinations
     indentified in the production batch record, [*] via overnight carrier.

6.   Reporting Requirements

     Copies of all batch records and QC data are to be sent to XOMA at the same
time as the ascites.

7.   Attachments

         1)       [*] Assessment Profile

         2)       Ascites [*] Test Requirements

XOMA CORPORATION

By:  /s/Nevada Blair                                  Date:  2/21/89
         Nevada Blair
         Production Planning, Inventory Control

CHARLES RIVER BIOTECHNICAL SERVICES, INC.

By:  /s/  Robert J. Judge                             Date: 2/22/89
         Robert J. Judge
         Vice President, Operations


                                        2


<PAGE>


                                                                       Exhibit A
                                                                          Page 3

                                  Attachment 1
                             CRBS Statement of Work
                                       [*]

                             [*] Assessment Profile

         Agent                                            Method

         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]
         [*]                                              [*]


                                        3


<PAGE>


                                                                       Exhibit A
                                                                          Page 4
                                  Attachment 2
                             CRBS Statement of Work
                                       [*]

                              [*] Test Requirements
         Agent                                             Method

         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]
         [*]                                               [*]


                                        4


<PAGE>


                                                                       Exhibit A
                                                                          Page 5

                              STATEMENT OF WORK TO
                  CHARLES RIVER BIOTECHNICAL SERVICES, INC. FOR
                      ASCITES PRODUCTION WITH [*] CELL LINE

1.   General

     Production procedures are to be performed in compliance with CGMP's.

2.   Cell Culture

     XOMA will supply a [*] cell line to be used [*] for each lot. The medium
     [*] is described in the [*] production batch record number [*]. An inoculum
     of [*] cells will be prepared as described in production batch record [*].

     [*]

3.   Ascites Production

     All ascites collection from mice must be carried out [*]

     [*] Only

     [*] may be used.

     [*] at least

     [*] prior to being used for production.

     [*]

     [*] Subsequent operations are performed following the procedure outlined

     [*]

4.   Testing and Specifications

     To be accepted by XOMA, the pooled [*] must meet the specifications
described in the paragraphs below. [*]


<PAGE>



                                                                       Exhibit A
                                                                          Page 6

     [*]

5.   Shipment

     Bulk ascites and samples are to be shipped to XOMA and other destinations
     identified in the production batch reocrd, [*] via overnight carrier.

6.   Reporting Requirements

     Copies of all batch records and QC data are to be sent to XOMA at the same
time as the ascites.

7.   Attachments

     1) [*] Assessment Profile

     2) Ascites [*] Test Requirements

XOMA CORPORATION

By:      /s/ Nevada Blair                   Date: 2-21-89
         Nevada Blair
         Production Planning, Inventory Control

CHARLES RIVER BIOTECHNICAL SERVICES, INC.

By:      /s/ Robert J. Judge                         Date: 2-21-89
         Robert J. Judge
         Vice President, Operations

                                        2


<PAGE>


                                                                       Exhibit A
                                                                          Page 7

                                  Attachment 1
                             CRBS Statement of Work
                                       [*]

                             [*] Assessment Profile


         Agent                                          Method

         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [* ]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]

                                        3


<PAGE>


                                                                       Exhibit A
                                                                          Page 8
                                  Attachment 2
                             CRBS Statement of Work
                                       [*]

                              [*] Test Requirements

         Agent                                          Method

         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]
         [*]                                            [*]

                                        4


<PAGE>


                                                                       Exhibit B

                                                  PURCHASE ORDER
Bill to: XOMA Corporation                            NO. 12/13/88
         2910 Seventh Street                         DATE     Shipping Point
         Berkeley, CA. 94710                                  FOB     Overnight
         Attn: Accts. Payable                                 VIA Net 30
                                                                           TERMS

TO:      Charles River Biotechnical SHIP          TO:XOMA Corporation
         251 Ballardvale Street                      890 Heinz Street
         Wilmington, MA 01887                        Berkeley, Ca. 97410
         Attn: Jack Wheeler                          Attn: Receiving

PLEASE SHIP THE FOLLOWING:          DATE REQUIRED:

ORDERED   REC'D   DESCRIPTION               PRICE            AMOUNT

[*]       [*]     Cell line [*] ascites     [*] ea.          [*]
[*]       [*]     Cell line [*] ascites     [*] ea.          [*]

                                                                Subtotal: [*]

                                                                Est Frt:  [*]

                                                                          [*]

          The above volumes refer to delivered ascites of which Xoma will
          guarantee to take [*]. Xoma and Charles River Biotechnical will at
          this time refer to the terms and conditions discussed on [*] at the
          Chicago Airport Hilton. This purchase order is for one year from the
          first shipment by Charles River Biotechnical. Delivery dates will be
          established by Nevada Blair at a future date and work will be
          performed according to previously received Statements of Work. Any
          increase or decrease in the above volumes must be prefaced by [*] days
          notice. Any total volume increase greater than [*] mice are subject to
          negotiation.

          E.D.A. As scheduled

          Note: Any additions or deletions to this purchase order are invalid
          without the approval of B. Kirby @ Xoma.

DATE RECEIVED AND DISPOSITION

                          ORDERED BY /s/ Bruce E. Kirby
                                         Bruce E. Kirby


<PAGE>


Exhibit B
Page 2

<TABLE>
                                                 XOMA CORPORATION
                                            Estimated Delivery Schedule
                                                   March 1, 1989

<CAPTION>
                PRODUCT: [*]                                                  PRODUCT: [*]
                                    Shipment                                                     Shipment
Volume (liters)                     To XOMA                   Volume (liters)                    To XOMA
<S>                                 <C>                       <C>                                <C>
[*]                                 [*]
[*]                                 [*]                       [*]                                [*]
[*]                                 [*]                       [*]                                [*]
[*]                                 [*]                       [*]                                [*]
[*]                                 [*]                       [*]                                [*]
[*]                                 [*]                       [*]                                [*]
[*]                                 [*]                       [*]                                [*]
[*]liters                                                     [*]liters
</TABLE>



<PAGE>


                                                                       Exhibit C

                                PRICING SCHEDULE


                                  CELL LINE [*]
                      Assumes yield of [*] post filtration

         [*]                 Liters                             Price/Liter

         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]


                                  CELL LINE [*]
                      Assumes yield of [*] post filtration

         [*]                 Liters                             Price/Liter

         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]
         [*]                 [*]                                [*]

[*]


<PAGE>


                                                                     EXHIBIT C-1

XOMA
CORPORATION
2910 SEVENTH STREET
BERKELEY, CA 94710
415/644-1170
TELEX: 856-697

March 6, 1989

Mr. John H. Wheeler
Vice President, Sales and Marketing
Charles River Biotechnical Services, Inc.
251 Ballardvale Street
Wilmington, MA  01887

Dear Jack:

After Charles River Biotechnical Services, Raleigh, North Carolina does [*] lots
of cell line [*], we will agree upon the yield per mouse and utilize the
attached page for the appropriate pricing level.

Sincerely,

Clarence L. Dellio
Vice President
Operations

Signed: /s/ John H. Wheeler                          Date: 3-7-89
                  John H. Wheeler
                  Vice President
                  Marketing & Sales

Signed: /s/ Clarence L. Dellio              Date: 3-7-89
                  Clarence L. Dellio
                  Vice President
                  Operations


<PAGE>



                              CELL LINE DESIGNATION
                                       [*]
             Assumes the following yields per mouse post filtration

[*]       [*]                                                  [*]
[*]       Liters           Price           Liters           Price

          [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]


[*]       [*]                              [*]
[*]       Liters           Price           Liters           Price

          [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]
[*]       [*]              [*]             [*]              [*]




[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission

                               AMENDMENT AGREEMENT

     THIS AMENDMENT AGREEMENT ("Amendment Agreement"), made as of this 17th day
of October, 1991, by and between CHARLES RIVER LABORATORIES, INC., a Delaware
corporation with its principal offices located at 251 Ballardvale Street,
Wilmington, Massachusetts 01887 ("CRL"), and XOMA CORPORATION, a Delaware
corporation with its principal offices located at 2910 Seventh Street, Berkeley,
California 94710 ("XOMA").

                               Background/Purpose

     XOMA and CRL entered into a Supply Agreement dated as of December 8, 1988
(as amended to date, the "Supply Agreement"), for the production by CRL of
murine ascites fluid ("Ascitic Fluid") from two cell lines owned by XOMA: N024
(or E5) for septic shock (the "E5 Product") and N020 (or H65) for graft-vs-host
reactions (together with the E5 Product, the "Products"). [*] the parties hereby
agree to amend the Supply Agreement in the manner set forth below.

     1. Nullification of Previous Amendment Agreement. By their execution of
this Amendment Agreement, CRL and XOMA hereby agree that the Amendment Agreement
dated as of March 1, 1991, between CRL and XOMA (the "Expansion Amendment"),
relating to the reservation of expansion space at CRL's ascites manufacturing
facilities in Raleigh, North Carolina (the "Raleigh Facility") and the
reimbursement of fixed facility and operating expenses by XOMA, shall be a
nullity as of December 31, 1991 and shall be of no further force or effect on or
after such date. The nullification of the Expansion Amendment shall not,
however, relieve either party of any duties or obligations thereunder,
including, without limitation, the obligation to pay any expenses, fees or
reimbursement amounts which were incurred pursuant to the Expansion Amendment on
or before December 31, 1991. In the event of a conflict between the terms of
this Amendment Agreement and the terms of the Expansion Amendment, the terms of
this Amendment Agreement shall prevail.

                                       -1-


<PAGE>


     2. Amendment of Existing Purchase Order. Pursuant to Section 14.1 of the
Supply Agreement, the Supply Agreement and Purchase Order #31100-2 currently
outstanding thereunder for calendar year 1991 (the "Existing Purchase Order")
are each hereby amended by substituting for the Existing Purchase Order the
purchase order attached hereto as Exhibit A (the "Modified 1991 Purchase
Order"). XOMA hereby acknowledges that it understands the terms of the Modified
1991 Purchase Order and agrees (i) to execute and deliver the Modified 1991
Purchase Order simultaneous with the execution of this Amendment Agreement and
(ii) that the Modified 1991 Purchase Order shall take effect upon execution and
shall supersede in all respects the Existing Purchase Order. CRL and XOMA
acknowledge and agree that the Modified 1991 Purchase Order, when read in
conjunction with Section 7 of this Amendment Agreement, requires XOMA to
guarantee payment to CRL of an aggregate of [*] for Ascitic Fluid produced by
CRL during calendar year 1991.

     3. 1992 Purchase Order. CRL and XOMA hereby agree that, during calendar
year 1992, CRL will deliver the quantities of Ascitic Fluid set forth on Exhibit
B hereto in accordance with the schedule set forth therein, which will result in
CRL delivering to XOMA a quantity of Ascitic Fluid sufficient to require XOMA to
pay CRL aggregate payments of at least [ * ] (the "1992 Minimum Payment") during
such calendar year. Ascitic Fluid which is available for delivery on a specified
date, but segregated and not shipped pursuant to Section 6 of this Amendment
Agreement, shall be deemed "delivered" for purposes of this Amendment Agreement.
Attached hereto as Exhibit C is a form of purchase order (the "1992 Purchase
Order"), which Purchase Order sets forth the specific terms necessary to ensure
that CRL receives not less than the 1992 Minimum Payment in connection with the
sale of Ascitic Fluid to XOMA in calendar year 1992. XOMA hereby acknowledges
that it has read and understands the terms of the 1992 Purchase Order and agrees
to execute and deliver the 1992 Purchase Order simultaneous with the execution
of this Amendment Agreement.

     4. Availability of Production Space. Effective January l, 1992, CRL hereby
agrees [*]

                                       -2-


<PAGE>


[*]. The reservation of the Reserved Space and, if necessary, the Expansion
Space shall be at no additional charge to XOMA, but XOMA shall under no
circumstances be relieved of its obligation to pay CRL, in accordance with the
terms of the 1992 Purchase Order, for any additional quantities of Ascitic Fluid
ordered by XOMA in excess of the amount required to ensure the 1992 Minimum
Payment. In its effort to meet any of XOMA's additional production requirements
for Ascitic Fluid, CRL will not be required to accelerate its production process
or increase the concentration of animals located in the Reserved Space or the
Expansion Space in a manner which CRL determines, in its reasonable business
judgment following consultation with XOMA, would likely impair CRL's ability to
maintain applicable health and safety standards including, without limitation,
health and safety standards applicable to the production of Ascitic Fluid, the
operation of the Facility, the well-being of persons in the facility or any
other health and safety standards imposed by law.

     5. Maintenance of Core Staff. CRL hereby agrees to maintain a core staff of
trained production, quality assurance and other key personnel at the Raleigh
Facility sufficient to (i) ensure the timely delivery of the 1992 Minimum
Requirement and (ii) meet any reasonable requests from XOMA for the production
of additional quantities of Ascitic Fluid in compliance with "Good Manufacturing
Procedures" as set forth in CRL's License Applications to the FDA.

     6. Segregation of E5 Product. If requested by XOMA, CRL will, subject to
reasonable space limitations, segregate but not ship E5 Product which is already
tested for, and has passed, release specifications (the "Segregated Inventory").
Title to and risk of loss of the Segregated Inventory shall pass to XOMA upon
segregation of the Segregated Inventory. When such Segregated Inventory is
subsequently shipped, CRL agrees to insure such Segregated Inventory during
shipment in accordance with CRL's customary practice of insuring Ascitic Fluid
in transit.

     7. Guarantee. XOMA shall be obligated to purchase [*] Products (i) to be
supplied by CRL in calendar year 1991 and (ii) delivered in calendar year 1992
which are necessary to ensure that XOMA will pay the 1992 Minimum Payment, as
specified in the Modified 1991 Purchase Order and 1992 Purchase Order,
respectively, and CRL shall be obligated to produce and deliver said guaranteed
amount. XOMA shall be obligated to purchase [*] to be supplied by CRL in
calendar year 1992 in excess of the amount

                                       -3-


<PAGE>


necessary to ensure that XOMA will pay the 1992 Minimum Payment and CRL shall be
obligated to produce and deliver such excess amount.

     8. Extension of Supply Agreement. Pursuant to Section 1.2 of the Supply
Agreement, the Supply Agreement shall be extended through December 31, 1992, to
include coverage of the deliveries scheduled for calendar year 1992.

     9. Other Terms. All other terms and conditions of the Supply Agreement
shall remain in full force and effect, except to the extent that modification is
necessary to reflect the nullification of the Expansion Amendment as of December
31, 1991 and the agreements set forth herein.

     10. Long-Term Agreement. The parties agree that, following FDA approval of
the E5 Product, the current supply arrangement evidenced by the Supply Agreement
will be extended for an additional period of not less than [*], and also
modified so as to [*].

     11. Notwithstanding anything to the contrary in the Supply Agreement, all
notices to be delivered to XOMA shall be directed to the attention of XOMA's
Legal Department.

     IN WITNESS WHEREOF, CRL and XOMA have caused this Amendment Agreement to be
executed by their duly authorized officers as of the day and year first above
written.

                                   CHARLES RIVER LABORATORIES, INC.

                                   By:  /s/ James C. Foster  10/21/91
                                            James C. Foster
                                            President and Chief Operating
                                            Officer

                                   XOMA CORPORATION

                                   By:  /s/ Clarence L. Dellio  10/17/91
                                            Clarence L. Dellio
                                            Senior Vice President

                                       -4-


<PAGE>


Facsimile of XOMA Purchase Order follows:

                                                                  Exhibit A
                                                        XOMA PURCHASE ORDER
                                                            31100 *REPRINT*
Ship to  XOMA II Receiving Dock
         XOMA Corporation
         890 Heinz Street
         Berkeley, CA  94710  x2021

Vendor   Charles River Biotechnical
         251 Ballardvale Street
         Wilmington, MA  01887
Phone    617 657-6500

Requestor         B. Dellio
Order date        10/17/91
Vendor Code       2222
Terms             Net 30
Ship via          O/N
F.O.B.            FACT
Freight           PPD
Taxable           NO
P.O. Type         REG
Account Number    See Below
Confirm to        J. Wheeler


ITEM              PART NUMBER/DESCRIPTION                     DELIVERY DATE

1                 101209                                      12/31/91
                  Ascites, E5, Purchased
                  ACCOUNT:  1200-100
2                 101204                                      CLOSED
                  Ascites, H65, Purchased
                  ACCOUNT:  1200-100
3                 101209                                      CLOSED
                  Ascites, E5, Purchased
                  ACCOUNT:  1200-100
4                 101204                                      04/10/91
                  Ascites, H65, Purchased
                  ACCOUNT:  1200-100
5                 MISC- 5-31100                               CLOSED
                  EDIM Adjustment
                  ACCOUNT:  1-5235-210


         AMENDMENT TO PURCHASE ORDER 31100-2
         XOMA guarantees to purchase 100% of PO#31100-4 requirements. Deliveries
         to be made in accordance with the attached delivery schedule. Terms and
         conditions of this purchase per supply agreement dated February 27,
         1989, as amended from time to time.

TOTAL ORDER $9,412,115.80

/s/Paul Bouchard
Authorized Agent
<PAGE>
EXHIBIT "B1"
XOMA PRODUCTION

[*]
<PAGE>
EXHIBIT "B2"
XOMA PRODUCTION

[*]
<PAGE>
Facsimile of XOMA Purchase Order follows:
                                    Exhibit C
                               XOMA PURCHASE ORDER
                                 35753 *REPRINT*
Ship to  XOMA II Receiving Dock
         XOMA Corporation
         890 Heinz Street
         Berkeley, CA  94710  x2021

Bill to  XOMA II Receiving Dock
         XOMA Corporation
         890 Heinz Street
         Berkeley, CA  94710  x2021

Vendor   Charles River Biotechnical
         251 Ballardvale Street
         Wilmington, MA  01887
Phone    617 657-6500

Requestor         B. Dellio
Order date        10/17/91
Vendor Code       2222
Terms             Net 30
Ship via          O/N
F.O.B.            FACT
Freight           PPD
Taxable           NO
P.O. Type         REG
Account Number    1200-100
Confirm to        J. Wheeler

ITEM              PART NUMBER/DESCRIPTION
1                 101209
                  Ascites, E5, Purchased

         Any incremental quantities ordered by XOMA shall result in a
         negotiation of a new, lower price based on volume for the full year.
         XOMA guarantees to purchase 100% of PO#35753 requirements in 1992. Any
         incremental quantities of E5 or H65 ascites purchases will be
         guaranteed at 50% level. Deliveries to be made in accordance with the
         attached delivery schedule. Additional terms and conditions supply
         agreement dated February 27, 1989.

TOTAL ORDER $2,964,144.00

/s/Paul Bouchard
Authorized Agent






This Exhibit contains material that has been omitted and confidential treatment
has been requested therefor. All such omitted material has been filed separately
pursuant to Rule 406. The omitted material throughout this Exhibit is indicated
by an "*".

                                    AGREEMENT

This Agreement is made as of the 31 day of August 1988 by and between XOMA
CORPORATION ("XOMA") a Delaware Corporation with its principal place of business
located at 2910 Seventh street, Berkeley, California, 94700, USA and SANOFI, a
French Corporation, with its principal place of business located 40, Avenue
George V, 75008 - Paris, France.

                                   WITNESSETH:

WHEREAS, Sanofi is a pharmaceutical company which has great experience in the
immunology field and which is a pioneer in the immunotoxins field, and is the
owner of various patents for Immunotoxins, and

WHEREAS, Xoma is a corporation which has performed innovative work in that field
and has already developed, among other things, H65 RTA a product currently used
in vivo bone marrow treatment, and

WHEREAS, Xoma is desirous of obtaining a license under Sanofi's patents referred
to above, and

WHEREAS, Sanofi has accepted to license said patents to Xoma under the terms and
conditions contained herein, and

WHEREAS, the purpose of this Agreement is to define Xoma's and Sanofi's rights
and obligations with respect to the granted rights.

NOW, THEREFORE, in consideration of the above stated premises and the promises
contained herein, it has been agreed as follows between Xoma and Sanofi.

<PAGE>
                                       -2-


ARTICLE 1 - DEFINITIONS

The following terms as used in this Agreement shall have the following meanings
unless otherwise indicated:

1.      Party or Parties shall mean respectively either Xoma or Sanofi as the
        context requires, or both Xoma and Sanofi.

2.      Affiliate(s) shall mean either a corporation or other business entity
        which, directly or indirectly, controls or is controlled by one of the
        Parties, or a company in which majority of the capital is owned by one
        of the Parties.

3.      Immunotoxin shall mean any preparation containing an antibody or
        fragment to which ricin A chain or any derivative is conjugated.

4.      Product shall mean any pharmaceutical preparation or formulation that
        includes an Immunotoxin.

5.      Selected Indications shall mean any preventive or curative therapeutic
        human treatment in any field except ophthalmology.

6.      Date of Commercialization shall mean the date after government general
        marketing approval has been given in a Country when any Product is first
        offered for sale by Xoma or one of its Affiliates in that Country.

7.      Net Sales shall mean the invoiced sales to a non Affiliate Party after
        the Date of Commercialization and after deducting:

        (a)     customary trade discounts; reasonable quantity and cash
                discounts;

        (b)     freight, delivery and insurance if included in the price;

        (c)     value added, sales, use or turnover taxes, and exercise taxes or
                customs duties included in the invoiced amount;

        (d)     rebates allowed to the purchaser of the Product pursuant to
                government regulations under any national health insurance
                program.

        (e)     returns

8.       Territory shall mean the whole world

<PAGE>
                                       -3-


9.      Patents shall mean all pending and issued patents filed by Sanofi or its
        Affiliates as of the date hereof relating to Immunotoxins. Exhibits 1
        and 2 sets forth, to the best of Sanofi's knowledge, a complete list
        thereof. The term Patents shall include any extensions, amendments,
        continuations, continuations in-part, foreign equivalents, divisional
        and reissue applications and reissue patents thereof, having claims
        directed to an Immunotoxin or directed to a method of making or using
        it.

10. Patents rights shall mean all rights derived from a Patent.

ARTICLE 2 - SUBJECT MATTER OF THE AGREEMENT:

Sanofi hereby grants to Xoma for the term of this Agreement a semi-exclusive
license under the Patents to use, develop, manufacture, sell and otherwise to
commercialize Products in the Territory for the Selected Indications.

Semi-exclusive means that Sanofi retains its rights under the Patents to develop
its own Products in its discretion and using the means it will elect to apply to
that development, to market its own Products through its subsidiaries, but
Sanofi will not give a license to a third party under any of the Patents for the
Selected Indications in the Territory except in one case: Sanofi may market its
own Products through a third party but in that case Xoma will be granted a right
of first refusal to the commercialization of such Products with respect to any
third parties.

The license to Xoma includes the right to sublicense to both affiliates and non
affiliates in whole or in part any of the rights licensed to it under this
Agreement provided that any sublicense granted by Xoma shall substantially
conform to the provisions of this Agreement. Xoma shall inform Sanofi before
negotiating any sublicense with a non affiliate for the sole purpose of
providing Sanofi with this information. Xoma shall also promptly inform Sanofi
when Xoma concludes an agreement with another.

ARTICLE 3 - TERM:

This Agreement shall enter into effect as of the date of its execution. For each
Product, in each country of commercialization, Xoma retains a royalty free right
to commercialize the Product after the end of the period of commercialization
which is subject to royalties according to article 4 of this Agreement.

<PAGE>
                                       -4-


ARTICLE 4 - ROYALTIES:

a)      So long as an issued Patent is in force in a country and covers a
        Product, whenever Xoma manufactures or sells the Product for a Selected
        Indication by itself or through an Affiliate to a non-affiliated third
        party it shall pay Sanofi a [*] royalty of Xoma's Net Sales for that
        country. If instead Xoma merely licenses a non-affiliated third party to
        commercialize the Product for a Selected Indication in such country , it
        shall pay Sanofi [*] of the net royalties it receives.

b)      Royalties payable by Xoma shall be reduced by any amounts reasonably
        paid (including license and legal fees) to third parties in connection
        with any claim that Xoma's sale of Products covered by the Patents
        infringes the rights of another in a manner within the scope of the
        Patents.

c)      If Sanofi licenses a third party to market Sanofi's own Products in a
        country in the Territory and Xoma does not exercise its right of first
        refusal and if the Sanofi Products are competitive with Xoma Products
        then being marketed or then under research and development by Xoma, then
        the royalty rate hereunder in those countries in which the Sanofi
        Products are introduced shall be reduced [*].

d)      Xoma agrees to pay Sanofi the total minimum annual royalties set forth
        below, which royalties shall be a credit against the royalty obligations
        incurred for any Products during the applicable year. The minimum
        royalties shall begin in the first fiscal year which is at least 12
        months after the Date of Commercialization of the first Product:

         Year 1                             25,000 $
         Years 2-3                          40,000 $
         Years 4-7                          50,000 $

ARTICLE 5 - PAYMENT OF ROYALTIES:

(i) Royalty payments made by Xoma to Sanofi shall be made at Sanofi's office
referred to above or such other place as Sanofi may designate in writing, within
ninety (90) days after the close of each sixmonth period.
Payment will continue on a semi-annual basis.

Each payment shall be accompanied by a true and complete statement of Product
sold by country, during the relevant period, showing the manner the royalties
were computed. Xoma shall maintain a special accounting procedure incorporating
all entries required for the accurate assessment of trading transactions made by
itself, its subsidiaries and licensees. This special account shall be made
available to Sanofi annually and in confidence until four years from the year of
compilation. <PAGE>
                                       -6-


(ii) All royalties made in countries other than the United States shall accrue
in the currency of the country in which the sales are made. Xoma shall convert
payments hereunder into U.S. dollars as long as permissible under local law, at
the exchange rate used by Xoma, in accordance with generally accepted accounting
principles for purposes of its certified financial statements.

Xoma will use its best efforts to secure U.S. dollar transfers in respect of
such royalty payments. In the event U.S. dollars are for any reason legally not
available for transfer, Xoma may discharge its royalty payment obligations by
depositing said royalty payments to the credit of Sanofi, or its nominee, in any
recognized banking institution to be designated by Sanofi in the country in
which the sales are made and in the currency of that country.


ARTICLE 6 - COMMERCIALIZATION - MAINTENANCE OF PATENTS:

a)       Xoma will use its commercially reasonable best efforts to develop and
         to commercialize as promptly and as efficiently as possible after the
         necessary governmental approvals have been obtained.

b)       Sanofi agrees to maintain the Patents in each country in which they are
         filed and to pursue diligently the issuance of any Patents filed but
         not yet issued. Sanofi will consult with Xoma on Patents not yet
         issued, or the extension, reissuance or amendment of the Patents and
         will give Xoma the opportunity, at its expense to advise in the scope
         and pursuit thereof.

c)      If either party learns of an infringement of, or other challenge to, the
        Patents by a third party, they shall consult on the proper course of
        action. If Sanofi elects not to defend, Xoma may do so and off-set
        royalties owed by any reasonable costs incurred. Benefits from any
        defense conducted by Xoma shall be split equally after costs are
        reimbursed. If Sanofi and Xoma agree to settle the matter or if for any
        other reason Sanofi is properly compelled to license others under the
        Patents, Xoma's royalty shall be reduced to 1% below the rate paid by
        the third party on competitive Products. If the infringement is not
        pursued by Sanofi or Xoma, Xoma's royalty on competitive Products in
        Japan, the United States and any European country shall be terminated
        when sales of the infringing entity equal 20% of Xoma's or its licensees
        sales in such country and shall be reduced by half in any other country
        in which that situation arises.

ARTICLE 7 - CONFIDENTIALITY:

Subject as herein provided, it is expressly agreed that any confidential
information, where applicable, received by either party under this Agreement is
submitted for use only in strict confidence and that during the term of this
Agreement and for a period of 5 years thereafter, the receiving party shall not
disclose any such confidential information to any third party without the
other's prior written consent; disclosure shall be exempt from this article to
extent that either party is able to prove that:

(a)     at the time of the communication the receiving Party previously had the
        information as evidenced by written documents;


<PAGE>

                                       -7-

(b)     the information is publicly divulged through no fault of the receiving
        party;

(c)     the information is supplied to receiving party by a third party who is
        under no obligation to the disclosing party to maintain such information
        in confidence; or

(d)     the information is developed by or for the receiving party independently
        of the disclosure made under this Agreement.

All such information shall be disclosed in writing and designated confidential
or, if disclosed orally, shall be confirmed in writing and designated
confidential within thirty (30) days of disclosure.

Each party shall make all necessary arrangements to cause its Affiliates and
their employees to comply with this obligation of secrecy.

ARTICLE 8 - RIGHT OF FIRST REFUSAL:

The right of first refusal given to Xoma for the commercialization of Sanofi's
Product will be exercized by Xoma on the following conditions:

Upon approval to commence Phase III efficacy human clinical trials or after
receipt of approval for general commercialization, Sanofi shall inform Xoma by
registered mail of Sanofi's intention to license a third party to market one of
Sanofi's own Products, in some portion of the Territory, the terms of the
proposed license and the identity of the licensee. Within 60 days of receipt of
this letter, Xoma shall respond whether it agrees to act as Sanofi's licensee
for that Product on terms which in material respects are equivalent to the
financial terms described by Sanofi. In its response, Xoma must set forth its
reasonable basis for believing it can effectively serve as Sanofi's licensee for
this Product. Sanofi and Xoma wish to cooperate in this regard and agree to use
their good faith, commercially reasonable best efforts to establish Xoma as the
licensee. If Sanofi nonetheless concludes in good faith that Xoma cannot
effectively perform the licensee responsibility or if Xoma does not exercise its
first refusal right, Sanofi may elect to conclude within 180 days of Xoma's
response an agreement with the original party on the specified terms. Sanofi
cannot materially change any of these terms in a manner adverse to it without
first so notifying Xoma and giving it the opportunity, for 30 days after receipt
of such information, to reconsider its decision. If Sanofi does not conclude its
agreement within such 180 days period (or 90 days after any Xoma opportunity for
reconsideration) Xoma's right of first refusal shall be reviewed on the same
terms as provided above.

If Xoma exercises its right of first refusal and becomes licensee of that Sanofi
Product, Sanofi agrees it will not market, directly or through another in that
part of the Territory a Product which addresses the same disease unless such
other Product demonstrates substantially improved performance from the Product
then marketed by Xoma.

<PAGE>

                                       -8-

Notwithstanding the foregoing, the Parties may mutually agree that it is
desirable for Sanofi to discuss possible licensing arrangements with Xoma prior
to entering discussions with others. The Parties will review this when the case
arises.

ARTICLE 9:

This Agreement does not preclude Xoma and Sanofi to conclude case by case
specified agreements related to, for example, research services or production of
Sanofi's own Products.

ARTICLE 10:

If, in the future, Sanofi for the commercialization of one of its Products needs
to have the license of one or several of Xoma's patents, Xoma will use its best
efforts to negotiate with Sanofi at that time in good faith.

ARTICLE 11:

Upon execution of the present Agreement, the legal proceedings between Sanofi
and Xoma will be terminated without prejudice.

ARTICLE 12 - TERMINATION:

12.1    In addition to pursuing all other remedies, either Party may terminate
        this Agreement on notice to the other Party if the other Party
        materially breaches any material obligation or representation under this
        Agreement and does not cure such breach and provide notice thereof to
        the other Party (i) within ninety days after written notice to the
        breaching Party setting forth, in reasonable detail, the nature of the
        alleged breach or (ii) if the alleged breach is contested in good faith,
        within 30 days of the resolution of such dispute in accordance with this
        Agreement.

12.2    This Agreement shall be terminated by operation of law in the event of
        suspension of activities because of the bankruptcy of Sanofi and/or
        Xoma.

12.3    Upon termination of this Agreement, its Articles 4 and 5 with respect to
        prior sales and 7 shall survive.

ARTICLE 13 - MISCELLANEOUS:

13.1    No agency

        The status of the Parties under this Agreement shall be that of
        independent contractors and neither Party shall be deemed or construed
        to be an employee, agent, partner or legal representative of the other
        Party for any purpose whatsoever. Neither Party shall have the right or
        authority to assume or otherwise create any obligation or
        responsibility, express or implied, on behalf or in the name of the
        other Party or to bind the other Party in any manner or thing
        whatsoever.
<PAGE>

                                       -9-

13.2    Entire Agreement

        This Agreement embodies the entire understanding of the Parties as it
        relates to the subject matter hereof, and this Agreement supersedes any
        prior agreements or understandings between the Parties with respect to
        such subject matter. No amendment or modification of this Agreement
        shall be valid and binding upon the Parties unless in writing and signed
        on behalf of each Party by its duly authorized officers.

13.3    Waiver

        Should either Party fail to enforce any provision of this Agreement, or
        fail to exercise, or waive, any right in respect thereto, such failure
        or waiver shall not be construed as constituting a waiver or continuing
        waiver of its rights to enforce such provision or right or any other
        provision or right.

13.4    Assignment

        This Agreement shall be binding upon and inure to the benefit of the
        Parties hereto and their respective heirs, successors and assigns;
        provided, however, that except as provided herein neither Party shall
        assign any of its rights or privileges hereunder without the prior
        written consent of the other Party, except to an Affiliate or to a
        successor in interest (or its equivalent) or in case of acquisition or
        merger of Xoma.

13.5    Notices

        Any notice, payment or report required or permitted under this Agreement
        shall be delivered by hand or by registered or certified mail to the
        following addresses:

         (a)  if to Xoma:
                                Xoma Corporation
                             att. Steven C. Mendell
                      Chairman and Chief Executive Officer
                               2910 Seventh Street
                          Berkeley - CA 94710 - U.S.A.

         (b) if to Sanofi:
                                     Sanofi
                               Att. Michel de Haas
                       Vice-President and General Counsel
                               40, Avenue George V
                             75008 - Paris - FRANCE
<PAGE>

                                      -10-

or to such other person or address as shall hereafter furnished by written
notice to the other Party.

13.6     Force majeure

         Each party shall be excused for failures and delays in performance
         caused by war, governmental proclamations, ordinances or regulations,
         or strikes, lockouts, floods, fires, explosions or other catastrophes
         beyond the reasonable control and without the fault of such Party. This
         provision shall not, however, release such Party from using its
         reasonable best efforts to avoid or remove all such causes, and such
         Party shall continue performance hereunder with the utmost dispatch
         whenever such causes are removed. Any Party claiming such excuse for
         failure or delay in performance shall give prompt notice thereof to the
         other Party, and neither Party shall be required to perform hereunder
         during the period of such excused failure or delay in performance
         except as otherwise provided herein.

13.7     Invalidity

         If any provision of this Agreement, or the application thereof to any
         situation or circumstance, shall be invalid or unenforceable, the
         remainder of this Agreement or the application of such provision to
         situations or circumstances other than those as to which it is invalid
         or unenforceable, shall not be affected; and each remaining provision
         of this Agreement shall be valid and enforceable to the fullest extent
         permitted by applicable laws. In the event of such partial invalidity,
         the Parties shall seek in good faith to agree on replacing any such
         legally invalid provisions by provisions which, in effect, will, from
         an economic viewpoint, most nearly and fairly approach the effect of
         the invalid provision.

13.8     Xoma indemnifies and holds harmless Sanofi and its agents, servants,
         and employees from and against any and all claims, demands, suits, or
         actions of any character presented or brought by third parties for
         injuries or death to persons and damages to property caused by or
         arising out of the testing, manufacture, sale or use by products by
         Xoma covered by the Patents, including any defects in such subject
         matter. This indemnity shall include, but not be limited to, court
         costs, attorneys' fees, costs of investigations and cost of defense
         associated with such demands, claims suits or actions. Sanofi shall
         promptly notify Xoma of any such claim which comes to its attention.
<PAGE>

                                      -11-

ARTICLE 14 - APPLICABLE LAW - ARBITRATION

This Agreement and matters in connection with the performance hereof shall be
construed, interpreted, applied and governed in all respects in accordance with
the laws of New York. Any disputes arising in connection with this Agreement
shall be finally settled under the Rules of Conciliation and Arbitration of the
International Chamber of Commerce in New York by one arbitrator mutually
agreeable to Xoma and Sanofi or by three arbitrators, one selected by each Party
and the third selected by these two. The prevailing party, as designated by the
arbitrator shall bear the other party's legal fees and costs of arbitration.

ARTICLE 15 - DISCLOSURE

The Parties agree to keep the terms hereof confidential. This Agreement will not
be filed with any governmental entity by any Party unless legally required and
then only after it has provided the other Party with a 10 days opportunity to
review the need for filing. Any filing will be made with requests for
confidentiality to the extent permitted by law.

IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be executed
in three originals by their duly authorized representatives on the date first
written above.

XOMA CORPORATION                            SANOFI


/s/ Richard C. Spalding                     /s/ Michel de Haas
- ------------------------------              --------------------------
By: Richard C. SPALDING                     By: Michel de HAAS
     Attorney in fact                       Vice-President
For: Steven C. MENDELL                      and General Counsel
     Chairman and
     Chief Executive Officer

<PAGE>

                          EXHIBIT 1 : LICENSED PATENTS

Ref.                       FILING NUMBER             PUBLICATION NUMBER

30 167 C                   78 27838                  27557 C
                           + 79 24655                44529 D
30 208 C                   81 07596                  95455 E

30 229 C                   81 21836                  54424 L

339 C                      83 13604                  85 082852


<PAGE>

                                   EXHIBIT - 2

                  EXTENSIONS OF THE LICENSED PATENTS INDICATED
                                       IN
                                   EXHIBIT - 1

<PAGE>

REFERENCE:  30167C
ASSIGNEE(S):  SANOFI
INVENTOR(S):  VOISIN GA JANSEN FK GROS P
<TABLE>
<CAPTION>

                                          FILING          APPLICATION             GRANTING       GRANTING
COUNTRY                                   DATE            NUMBER                  DATE           NUMBER
<S>                                       <C>             <C>                     <C>            <C>

CANADA                                    790926          336,385                 850611         1188681
FRANCE                                    791003          79 24655                830801         79 24655
FRANCE                                    780928          78 27838                830426         78 27838
GERMAN FEDERAL REPUBLIC                   790927          29 39 165.9             0
ITALY                                     790928          26118 A/79              0
JAPAN                                     790928          54-125257               0
NETHERLANDS                               790928          7907251                 0
SPAIN                                     790928          484591                  801216         484591
SWEDEN                                    790926          7907994-3               861211         7907994-3
SWITZERLAND                               790926          8644/79-7               850131         647411
UNITED KINGDOM                            790928          7933670                 840104         2 034 324
UNITED STATES                             790927          79,441                  820720         4,340,535
</TABLE>

EUROPEAN PATENT DESIGNATED COUNTRY
PATENT COOPERATION TREATY (PCT) DESIGNATED COUNTRY


<PAGE>


REFERENCE:  30208C
ASSIGNEE(S):  SANOFI
INVENTOR(S):  JANSEN FK GROS P

<TABLE>
<CAPTION>
                                          FILING          APPLICATION             GRANTING       GRANTING
COUNTRY                                   DATE            NUMBER                  DATE           NUMBER
<S>                                       <C>             <C>                     <C>            <C>
AFRICAN UNION                             820413          57657                   830331         7069
ARGENTINA                                 820412          289.058                 830228         228.394
AUSTRALIA                                 820408          82510/82                870319         556,641
AUSTRIA                                   0                                       0
BELGIUM                                   0                                       0
CANADA                                    820407          400,606                 851015         1195248
CZECHOSLOVAKIA                            820409          2564-82                 0
DENMARK                                   820414          82.1674                 0
EGYPT                                     820414          205/82                  0
EUROPEAN PATENT                           820409          82400651.4              860129         0063988
FINLAND                                   820414          821304                  0
FRANCE                                    0                                       0
FRANCE                                    810415          81 07596                851014         81 07596
GERMAN DEMOCRATIC
REPUBLIC                                  820414          60694                   831214         204849
GERMAN FEDERAL REPUBLIC                   0                                       0
GREECE                                    820409          67862                   820506         69199
HUNGARY                                   820414          1135/82                 850826         188314
INDONESIA                                 820415          8624                    0
IRELAND                                   820406          815/82                  0
ISRAEL                                    820406          65441                   851231         65441
ITALY                                     850522          67710/BE/85             0
JAPAN                                     820415          57-061857               0
LIECHTENSTEIN                             0                                       0
LUXEMBOURG                                0                                       0
MOROCCO                                   820401          19633                   821231         19429
NETHERLANDS                               0                                       0
NEW ZEALAND                               820414          200302                  850909         200302
NORWAY                                    820413          82/1198                 870114         154905
PANAMA                                    820623                                  0
PHILIPPINES                               820415          27142                   870508         20846
POLAND                                    820415          P 235981                0
PORTUGAL                                  820413          74741                   831109         74741
REP. OF CHINA (TAIWAN)                    820426          7111360                 830516         18422
SOUTH AFRICA                              820414          82/2528                 830223         82/2528
SOUTH KOREA                               820415          1664/1982               0
SPAIN                                     820414          511433                  821204         511433
SWEDEN                                    0                                       0
SWITZERLAND                               0                                       0
TUNISIA                                   820413          14828                   830130         14828
</TABLE>

EUROPEAN PATENT DESIGNATED COUNTRY
PATENT COOPERATION TREATY (PCT) DESIGNATED COUNTRY

<PAGE>

REFERENCE:  30208C
ASSIGNEE(S):  SANOFI
INVENTOR(S):  JANSEN FK GROS P

<TABLE>
<CAPTION>
                                          FILING          APPLICATION             GRANTING       GRANTING
COUNTRY                                   DATE            NUMBER                  DATE           NUMBER
<S>                                       <C>             <C>                     <C>            <C>
UNITED KINGDOM                            0                                       0
UNITED STATES                             820414          368,434                 831108         4,414,148
USSR                                      820414          3427002/13              0
VENEZUELA                                 820414          660                     0
YUGOSLAVIA                                820414          P-830/82                0
</TABLE>

EUROPEAN PATENT DESIGNATED COUNTRY
PATENT COOPERATION TREATY (PCT) DESIGNATED COUNTRY

<PAGE>

REFERENCE:  30229C
ASSIGNEE(S):  SANOFI
INVENTOR(S):  CASELLAS P GROS P JANSEN F

<TABLE>
<CAPTION>
                                          FILING          APPLICATION             GRANTING       GRANTING
COUNTRY                                   DATE            NUMBER                  DATE           NUMBER
<S>                                       <C>             <C>                     <C>            <C>
AUSTRALIA                                 821110          90334/82                0
AUSTRIA                                   0                                       0
BELGIUM                                   0                                       0
CANADA                                    821103          414,789                 860812         1209472
EUROPEAN PATENT                           821115          82402078.8              0
FRANCE                                    0                                       0
FRANCE                                    811120          81 21836                851014         81 21836
GERMAN FEDERAL REPUBLIC                   0                                       0
ITALY                                     0                                       0
JAPAN                                     821120          57-202905               0
LIECHTENSTEIN                             0                                       0
LUXEMBOURG                                0                                       0
NETHERLANDS                               0                                       0
NEW ZEALAND                               821119          202563                  860924         202563
SOUTH AFRICA                              821103          82/8048                 830831         82/8048
SWEDEN                                    0                                       0
SWITZERLAND                               0                                       0
UNITED KINGDOM                            0                                       0
UNITED STATES                             821101          438,037                 870217         4,643,895
UNITED STATES                             861107          928,863                 0
</TABLE>

EUROPEAN PATENT DESIGNATED COUNTRY
PATENT COOPERATION TREATY (PCT) DESIGNATED COUNTRY

<PAGE>

REFERENCE:  339O
ASSIGNEE(S):  SANOFI
INVENTOR(S):  JANSEN F GROS P

<TABLE>
<CAPTION>
                                          FILING          APPLICATION             GRANTING       GRANTING
COUNTRY                                   DATE            NUMBER                  DATE           NUMBER
<S>                                       <C>             <C>                     <C>            <C>
BELGIUM                                   0                                       0
EUROPEAN PATENT                           840821          84401694.9              880107         0140728
FRANCE                                    0                                       0
FRANCE                                    830823          83 13604                851125         83 13604
GERMAN FEDERAL REPUBLIC                   0                                       0
ITALY                                     0               67176/BE/88             0
JAPAN                                     840823          59-175800               0
LIECHTENSTEIN                             0                                       0
LUXEMBOURG                                0                                       0
NETHERLANDS                               0                                       0
SWEDEN                                    0                                       0
SWITZERLAND                               0                                       0
UNITED KINGDOM                            0                                       0
UNITED STATES                             840817          641,582                 0
UNITED STATES                             880115          144,126                 0
</TABLE>

EUROPEAN PATENT DESIGNATED COUNTRY
PATENT COOPERATION TREATY (PCT) DESIGNATED COUNTRY














[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission.

                              AMENDED AND RESTATED
                         RESEARCH AND LICENSE AGREEMENT
                                     BETWEEN
                                XOMA CORPORATION
                                       AND
                               NEW YORK UNIVERSITY

<PAGE>


                                    NYU/XOMA
                              AMENDED AND RESTATED
                         RESEARCH AND LICENSE AGREEMENT

<TABLE>
<CAPTION>
                                                      I N D E X
<S>                        <C>                                                                   <C>
Section l.                 Definitions                                                           page 3

Section 2.                 Effective Date                                                        page 10

Section 3.                 Performance of the NYU Research Project                               page 10

Section 4.                 Funding of the NYU Research Protect                                   page 12

Section 5.                 Title                                                                 page 13

Section 6.                 Patents and Patent Applications                                       page 14

Section 7.                 Grant of License                                                      page 16

Section 8.                 Development and Commercialization                                     page 18

Section 9.                 Payments for License                                                  page 20

Section 10.                Method of Payment                                                     page 27

Section 11.                Publication                                                           page 28

Section 12.                Infringement of NYU Patent                                            page 29

Section 13.                Term and Termination                                                  page 33

Section 14.                CORPORATION's Contingent
                           Right to Royalties                                                    page 34

Section 15.                CORPORATION's Indemnification                                         page 35

Section 16.                Security for Indemnification                                          page 36

Section 17.                Confidential Information                                              page 40

Section 18.                Representations and Covenants                                         page 41

Section 19.                No Assignment                                                         page 42

Section 20.                Use of Name                                                           page 43

Section 21.                Miscellaneous                                                         page 44
</TABLE>

         Appendix I - Pre-Existing Inventions

         Appendix II - Research Project

         Appendix III - Development Plan

         Appendix IV - Schedule of Research Payments

<PAGE>

                                    NYU/XOMA
                         RESEARCH AND LICENSE AGREEMENT

     This Agreement, dated as of September 1, 1993, is by and between:

     NEW YORK UNIVERSITY a corporation organized and existing under the laws of
the State of New York and having a place of business at 70 Washington Square
South, New York, New York 10012 (hereinafter "NYU")

                                      AND

     XOMA Corporation a corporation organized and existing under the laws of the
State of Delaware having its principal office at 2910 Seventh Street, Berkeley,
California 94710 (hereinafter "CORPORATION").

                                   WITNESSETH:

     WHEREAS, CORPORATION and NYU are parties to that certain Agreement dated
August 6, 1990 ("the Original Agreement") and each of them desires to amend and
restate the Original Agreement in its entirety;

     NOW, THEREFORE, in consideration of the mutual promises and agreements
contained herein, CORPORATION and NUY mutually covenant and agree that the terms
of the Original Agreement shall be cancelled and that, effective August 6, 1990
("the Effective Date") the following recitals and terms shall be substituted
therefore:

                                       -1-
<PAGE>
                                    RECITALS

     WHEREAS, Drs. Peter Elsbach and Jerrold Weiss of NYU (hereinafter "the NYU
Scientists") have made certain inventions relating to Bactericidal/Permeability
Increasing Protein (hereinafter "the BPI Pre-Existing Inventions"), and also
certain inventions relating to 15KD proteins purified from mammalian
polymorphonuclear leukocytes and having anti-bacterial or lipopolysaccharide
neutralizing properties ("the P15 Pre-Existing Inventions") all as more
particularly described in pending U.S. patent application and counterpart
foreign patent applications owned by NYU, identified, respectively, in annexed
Appendix I and Appendix II forming an integral part hereof;

     WHEREAS, NYU is willing to perform the NYU Research Project (as hereinafter
defined);

     WHEREAS,  CORPORATION  is prepared to sponsor the NYU Research  Project (as
hereinafter defined) at the facilities of NYU;

     WHEREAS, subject to the terms and conditions hereinafter set forth, NYU is
willing to grant to CORPORATION and CORPORATION is willing to accept from NYU a
license to use and practice the Research Technology (as hereinafter defined) for
the manufacturing and marketing of the Licensed Products (as hereinafter
defined);

     NOW,  THEREFORE,  IT IS HEREBY  DECLARED AND AGREED  BETWEEN THE PARTIES AS
FOLLOWS:

                                       -2-
<PAGE>
1.   Definitions.

     Whenever used in this Agreement, the following terms shall have the
     following meanings:

     a.   "Affiliate" shall mean any company or other legal entity which
          controls, or is controlled by, or is under common control with, a
          sublicensee of CORPORATION; control means the holding of fifty and one
          tenth percent (50.1%) or more of (i) the capital and/or (ii) the
          voting rights and/or (iii) the right to elect or appoint directors or
          such lower maximum amount allowed by the law governing the ownership
          of said organization.

     b.   "Agreement Year" shall mean any consecutive period of twelve months
          commencing on the Effective Date or an annual anniversary of the
          Effective Date.

     c.   "BPI"  shall  mean   Bactericidal/Permeability   Increasing   protein,
          purified from mammalian polymorphonuclear leukocytes.

     d.   "BPI Biological Material" shall mean the cDNA encoding for human BPI
          that NYU has in its possession on the Effective Date.

     e.   "BPI Products" shall mean:





                                       [*]

                                       -3-
<PAGE>
                                       [*]
                                       -4-
<PAGE>
                                       [*]

     f.   "BPI Combination Product" shall mean a product comprising a BPI
          Product(s) and at least one other ingredient which is therapeutically
          or prophylactically active.

     g.   "CORPORATION Entity" shall mean any company or other legal entity
          which controls, or is controlled by, or is under common control with,
          CORPORATION; control means the holding of fifty and one tenth percent
          (50.1%) or more of (i) the capital and/or (ii) the voting rights
          and/or (iii) the right to elect or appoint directors or such lower
          maximum amount allowed by the law governing the ownership of said
          organization.

     h.   "CORPORATION PATENTS" shall mean all United States and foreign patents
          and reissues, renewals and extensions thereof, and patent
          applications, and any divisions, continuations, in whole or in part
          therefor, which name only employee(s) of CORPORATION and not any NYU
          employee as an inventor(s) thereon and relate to the BPI Products, as
          defined herein.

     i.   "Development Plan" shall mean the preclinical plan and estimated time
          frame for clinical program, through final approval by the United
          States Food and Drug Administration ("FDA") for the BPI Products, as
          set forth in Appendix III, attached hereto and made an integral part
          hereof.

                                       -5-
<PAGE>
     j.   "JOINT  Patents" shall mean all United States and foreign  patents and
          reissues,  renewals and extensions thereof,  and patent  applications,
          and any divisions,  continuations, in whole or in part therefor, which
          name at least one employee of CORPORATION  and one employee or student
          of NYU as inventors  thereon and which  disclose and claim  inventions
          which are based on, use or comprise  biological  material  provided to
          CORPORATION  by NYU or disclosed in the NYU Patents or which relate to
          the BPI Products.

     k.   "License" shall mean the exclusive worldwide license to practice the
          Research Technology for the development, manufacture, use and sale of
          the Licensed Products.

     l.   "Licensed Product" shall mean (aa) any BPI Product; or (bb) any BPI
          Combination Product; or (cc) any P15 Product (as hereinafter defined);
          or (dd) any P15 Combination Product (as hereinafter defined). The
          production, use or sale of which is covered by a claim of any
          unexpired NYU Patent and/or JOINT Patent and/or CORPORATION Patent
          which has not been disclaimed or held invalid by a court of competent
          jurisdiction from which no appeal can be taken.

     m.   "Net Sales" shall mean the total amount invoiced in connection with
          sales of the Licensed Products, in any arm's length transaction, after
          deduction of all the following to the extent applicable to such sales;

                                       -6-
<PAGE>
          i)   all  trade,  case and  quantity  credits,  discounts,  refunds or
               rebates;

          ii)  allowances or credits for returns;

          iii) sales commissions; and iv) sales taxes (including value added
               tax), provided that in respect of sales which are not "at arm's
               length" sales, the Net Sales shall be deemed to be the total
               sales price invoiced at the time of such sales for sales of
               Licensed Products which are "at arm's length" sales after the
               aforementioned deductions.


     n.   "NYU Know-How" shall mean the BPI and P15 Pre-Existing  Inventions and
          any information and materials,  including the BPI Biological  Material
          and the  P15  Biological  Material  and  also,  but  not  limited  to,
          pharmaceutical,   chemical,   biological  and  biochemical   products,
          information,  trade  secrets,  know-how,  technical and  non-technical
          data,  methods  and  processes  and  any  drawings,  plans,  diagrams,
          specifications  and/or other documents  containing  such  information,
          discovered,  developed  or acquired  by, or on behalf of,  students or
          employees of NYU during the Research Period (as  hereinafter  defined)
          and in the course of the NYU Research Project.

     o.   "NYU Patents" shall mean all United States and foreign patents and
          reissues, renewals and extensions thereof, and patent applications,
          and any divisions, continuations, in whole or in part, therefor:

                                       -7-
<PAGE>
                    (1) which claim Pre-Existing Inventions and which are
               identified on annexed Appendix I; or

                    (2) which claim inventions that are made by students or
               employees of NYU during the term and in the course of the NYU
               Research Project.

     p.   "NYU Research Project" shall mean the investigations during the
          Research Period (as hereinafter defined) into the field of BPI and P15
          (as hereinafter defined) under the supervision of the NYU Scientists
          at NYU in accordance with the research program, described in annexed
          Appendix III, which forms an integral part hereof.

     q.   "PLA" shall mean 15KD proteins purified from mammalian
          polymorphonuclear leukocytes and having anti-bacterial or
          lipopolysaccharide neutralizing properties.

     r.   "P15 Products" shall mean:

                                      [*]

                                       -8-
<PAGE>
                           [*]
                  s. "P15 Biological Material" shall mean the encoding for
                  mammalian P15s that NYU had in its possession on September 1,
                  1993. t. "P15 Combination Product" shall mean a product
                  comprising a P15 Product(s) and at least one other ingredient
                  which is therapeutically or prophylactically active.

                                       -9-
<PAGE>
     u.   "PLA" shall mean a product license application filed with the FDA with
          respect to any BPI Product or P15 Product.

     v.   "Research Period" shall mean the six (6) year period commencing upon
          the Effective Date and any extension thereof as to which NYU and
          CORPORATION shall mutually agree in writing.

     w.   "Research Technology" shall mean all NYU Patents and NYU Know-How and
          NYU's interest in JOINT Patents.

2.   Effective Date.

     This Agreement shall be effective as of August 6, 1990 (the "Effective
     Date") and shall remain in full force and effect until it expires or is
     terminated in accordance with Section 13 or Sections 8.e. or 9.f. hereof.

3.   Performance of the NYU Research Project.

     a.   In consideration of the sums to be paid to NYU as set forth in Section
          4 below,  NYU  undertakes  to perform the NYU Research  Project at NYU
          under the  supervision  of the NYU  Scientists  during  the three year
          period  commencing on the Effective Date,  (hereinafter  "the Research
          Period").  If,  during the Research  Period all of the NYU  Scientists
          shall cease to  supervise  the NYU  Research  Project,  then NYU shall
          provide notice to CORPORATION of such occurrence and shall endeavor to
          find from  among  the  scientists  of NYU a  scientist  or  scientists
          acceptable  to  CORPORATION  to continue  the  supervision  of the NYU
          Research  Project in place of the NYU Scientists.  If NYU is unable to
          find such a scientist

                                      -10-
<PAGE>
          acceptable to CORPORATION, which acceptance shall not unreasonably be
          withheld, within three months after such notice to CORPORATION,
          CORPORATION shall have the option to terminate its funding of the NYU,
          Research Project. CORPORATION shall promptly advise NYU in writing if
          CORPORATION so elects. Such termination of funding pursuant to this
          Section 3.a. shall not terminate this Agreement or the License granted
          herein. Nothing herein contained, however, shall be deemed to impose
          an obligation on NYU to find a replacement for the NYU Scientists.

     b.   Nothing contained in this Agreement shall be construed as a warranty
          on the part of NYU that any results or inventions will be achieved by
          the NYU Research Project, or that the Research Technology and/or any
          other results or inventions achieved by the NYV Research Protect, if
          any, are or will be commercially exploitable and furthermore, NYU
          makes no warranties whatsoever as to the commercial or scientific
          value of the Research Technology.

     c.   Within sixty (60) days after each six months of the Research Period,
          NYU shall prepare a written report summarizing the results of the work
          conducted on the NYU Research Project during the preceding period. 

     d.   NYU will have full authority and responsibility for the NYU Research
          Project. All students and employees of NYU who work on the NYU
          Research Project will do so as employees or students of NYU, and not
          as employees of CORPORATION.

                                      -11-
<PAGE>
     e.   Within seven (7) days after the Effective Date, NYV shall deliver to
          CORPORATION a sample of the Biological Material. CORPORATION shall use
          such Biological Material solely for performance of the CORPORATION's
          research and development obligations pursuant to Section 8 hereof, and
          CORPORATION shall not distribute or disclose the Biological Material
          to any person or entity outside CORPORATION without the prior written
          permission of NYU.

4. Funding of the NYU Research Project.

     a.   As compensation to NYU for work performed on the NYU Research  Project
          during the Research Period,  CORPORATION  shall pay NYU a total of [*]
          payable in accordance with the Schedule  annexed hereto as Appendix V,
          which is an integral part of this Agreement.  NYU acknowledges that as
          of September 1, 1993,  CORPORATION has paid NYU [*] of such amount. 

     b.   Nothing in this Agreement shall be interpreted to prohibit NYU (or
          the NYU Scientists) from obtaining additional financing or research
          grants for the NYU Research Project from government agencies, which
          grants or financing may render all or part of the NYU Research Project
          and the results thereof subject to the patent rights of the U.S.
          government and its agencies, as set forth in Title 35 U.S.C. ss.200 et
          seq., and from non-commercial third parties, provided, however, that
          such grants 



                                      -12-
<PAGE>

          shall not give such non-commercial third parties any rights to the
          results, use and/or commercialization of such research.

5.   Title.

     a.   Subject to the License  granted to  CORPORATION  hereunder  and to the
          rights of the United  States  Government  pursuant  to Title 35 of the
          U.S.C. ss.200 et. sec. and 15 CFR ss.368 et. seq., it is hereby agreed
          that all right, title and interest, in and to the Research Technology,
          and in and to any drawings, plans, diagrams, specifications, and other
          documents  containing any of the Research Technology shall vest solely
          in NYU. At the request of NYU, CORPORATION shall take all steps as may
          be necessary to give full effect to said right,  title and interest of
          NYU including, but not limited to, the execution of any documents that
          may be  required to record such  right,  title and  interest  with the
          appropriate  agency or government  office.  If CORPORATION  determines
          that a waiver is necessary  with  respect to the Research  Technology,
          from the United States Government, CORPORATION shall so notify NYU and
          NYU shall assist  CORPORATION in applying for such waiver.

     b.   Title to JOINT Patents shall vest jointly in NYU and CORPORATION,
          except as otherwise provided herein.

     c.   NYU and CORPORATION acknowledge that there is a possibility Genentech
          or an assignee thereof might claim certain rights to and/or interest
          in the BPI Pre-Existing Inventions.

                                      -13-
<PAGE>
6.   Patents and Patent Applications.

     a.   CORPORATION has paid NYU the sum of U.S. [*] being the amount of all
          costs and fees incurred by NYU up to the Effective Date in connection
          with the patent applications identified in Appendix I hereto. Within
          thirty (3) days of final execution of this Agreement, CORPORATION
          shall pay NYU the sum of [*], being the amount of all costs and fees
          incurred by NYU after the Effective Date and with respect to the
          patent applications identified in Appendix II hereof.

     b.   NYU shall promptly disclose to CORPORATION in writing all inventions
          which comprise potential NYU Patents or JOINT Patents. CORPORATION
          shall promptly disclose to NYU in writing all inventions which
          comprise potential JOINT Patents or CORPORATION Patents.

     c.   At the initiative of CORPORATION or NYU, the parties shall consult
          with each other regarding the filing of patent applications in respect
          of any inventions which comprise potential NYU Patents or JOINT
          Patents, including but without limitation, the timing of the filing of
          such applications, the jurisdiction within which foreign counterparts
          of such applications should be filed and other details pertaining to
          the prosecution and maintenance of patent rights.

     d.   NYU and CORPORATION will negotiate in good faith to select patent
          counsel mutually acceptable to NYU and CORPORATION.

                                      -14-
<PAGE>
          NYU and CORPORATION will file, prosecute and maintain through such
          patent counsel and in countries selected by NYU and CORPORATION,
          patent applications on any inventions which comprise potential JOINT
          Patents. NYU and CORPORATION shall each be solely responsible for the
          filing, prosecution and maintenance of NYU Patents and CORPORATION
          Patents respectively.

     e.   NYU and CORPORATION shall assist, and cause their respective employees
          and consultants to assist each other, in assembling inventorship
          information and data for the filing and prosecution of patent
          applications on inventions which comprise potential NYU Patents or
          JOINT Patents.

     f.   All NYU Patents and JOINT Patents shall be filed, prosecuted and
          maintained at the expense of CORPORATION.

     g.   If at any time during the term of this Agreement  CORPORATION  decides
          that it is  undesirable as to one or more  countries,  to prosecute or
          maintain  any  potential  or  issued  NYU  Patents  or JOINT  Patents,
          CORPORATION  shall give prompt written notice thereof to NYU, and upon
          receipt  of  such  notice  CORPORATION  shall  be  released  from  its
          obligation to bear all of the expense to be incurred  thereafter as to
          such   countries  in   conjunction   with  such  patent(s)  or  patent
          application(s), and NYU shall have the right to prosecute and maintain
          such patents at NYU's sole expense.

     h.   Nothing herein contained shall be deemed to be a warranty by NYU that

                                      -15-
<PAGE>
               i) NYU can or will be able to obtain any patent or patents on any
          patent application or applications in the NYU Patents or any portion
          thereof, or that any of the NYU Patents will afford adequate or
          commercially worthwhile protection, or

               ii) that the manufacture, use, or sale of any element of the
          Research Technology or any Licensed Product will not infringe any
          patent(s) of a third party.

7.   Grant of License.

     a.   Subject to the terms and conditions hereinafter set forth, and subject
          to any rights of the United States Government pursuant to Title 35 of
          the United States Code ss.200 et seq., NYU hereby grants to
          CORPORATION and CORPORATION hereby accepts from NYU the License.

     b.   The period of the License shall be determined on a  country-by-country
          basis and on a Licensed Product-by-Licensed Product basis and shall be
          for the longer of (i) fifteen (15) years after first  commercial  sale
          after regulatory  approval in such country of the respective  Licensed
          Product by CORPORATION, or CORPORATION's  sublicensees,  or (ii) until
          the last to expire of the NYU  Patents  or the JOINT  Patents  in such
          country,  and, thereafter,  in the case of (i) or (ii),  CORPORATION's
          license

                                      -16-
<PAGE>
          hereunder with respect to the Licensed Product shall be a fully
          paid-up irrevocable license without payment of additional royalties.
          The CORPORATION shall inform NYU in writing of the date of first
          commercial sale after regulatory approval of each Licensed Product in
          each such country as soon as practicable after the making of such
          commercial sale.

     c.   CORPORATION  shall be entitled to grant  sublicenses under the License
          on terms and  conditions in compliance and not  inconsistent  with the
          terms and conditions of this Agreement (i) to a CORPORATION  Entity or
          (ii) to other third parties for  consideration  and in an  arms-length
          transaction.  All  sublicenses  shall only be  granted by  CORPORATION
          under a written  agreement,  a copy of which,  with certain  financial
          terms  deleted,  shall be submitted by  CORPORATION  to NYU as soon as
          practicable  after the signing  thereof.  Each  sublicense  granted by
          CORPORATION  hereunder  shall be subject and  subordinate to the terms
          and  conditions of this Agreement and shall contain  (inter-alia)  the
          following provisions:

               (1) the sublicense shall expire automatically on the termination
          of the License; provided, however that upon such termination, the
          sublicensee shall have the right to enter into a licensing agreement
          with NYU upon the same terms and conditions as in this Agreement.

               (2) the sublicense  shall not be assignable,  in whole or in part
          except to an Affiliate of the sublicensee;

                                      -17-
<PAGE>
               (3) the sublicensee shall not grant further sublicenses except to
          an Affiliate of the sublicensee; and

               (4) both during the term of the sublicense and thereafter the
          sublicensee shall be bound by a secrecy obligation similar to that
          imposed on CORPORATION in Section 17 below, and that the sublicensee
          shall bind its employees, both during the terms of their employment
          and thereafter, with a similar undertaking of secrecy.

               (5) the sublicense agreement shall include the text of Section 15
          and 16 of this Agreement and shall state that NYU is an intended third
          party beneficiary of such sublicense agreement for purposes of
          enforcing such indemnification and insurance provisions.

8.   Development and Commercialization.

     a.   CORPORATION  undertakes to use  reasonable  diligence to carry out the
          Development Plan, including but not limited to, the performance of all
          efficacy,  pharmaceutical,  safety,  toxicological and clinical tests,
          trials and  studies  and all other  activities  necessary  in order to
          obtain the approval of the FDA for the production, use and sale of the
          Licensed Products, all as set forth in the Development Plan and within
          all timetables set forth therein.  CORPORATION  further  undertakes to
          exercise  due  diligence  and to employ its  reasonable  diligence  to
          obtain or to

                                      -18-
<PAGE>
          cause its sublicensees to obtain, the appropriate approvals of the
          health authorities for the production, use and sale of the Licensed
          Products, in each of the other countries of the world in which
          CORPORATION or its sublicensees intend to produce, use, and/or sell
          Licensed Products.

     b.   Provided that applicable laws, rules and regulations  require that the
          performance  of  the  tests,  trials,  studies  and  other  activities
          specified in  subsection  a. above shall be carried out in  accordance
          with FDA Good Laboratory  Practices and in a manner  acceptable to the
          relevant health  authorities,  CORPORATION shall carry out such tests,
          trials,  studies  and other  activities  in  accordance  with FDA Good
          Laboratory Practices and in a manner acceptable to the relevant health
          authorities.  Furthermore,  the Licensed Products shall be produced in
          accordance with FDA Good Manufacturing  Practice ("GMP") procedures in
          a facility  which has been certified by the FDA as complying with GMP,
          provided that applicable laws, rules and regulations so require.

     c.   CORPORATION undertakes to begin the regular commercial production,
          use, and sale of the Licensed Products in good faith in accordance
          with the Development Plan and to continue diligently thereafter to
          commercialize the Licensed Products.

     d.   CORPORATION shall provide NYU with written reports on all activities
          and actions undertaken by CORPORATION to develop and commercialize the
          Licensed Products; such reports shall be made

                                      -19-
<PAGE>
          within sixty (60) days after each six (6) months of the duration of
          this Agreement, commencing six months after the Effective Date.

     e.   If CORPORATION  shall not commercialize the Licensed Products within a
          reasonable  time frame,  unless such delay is  necessitated  by FDA or
          other regulatory  agencies or unless NYU and CORPORATION have mutually
          agreed  to  amend  the   Development   Plan   because  of   unforeseen
          circumstances,   NYU  shall   notify   CORPORATION   in   writing   of
          CORPORATION's  failure to  commercialize  and shall allow  CORPORATION
          sixty (60) days to cure its failure to  commercialize.  If CORPORATION
          falls to cure such delay to NYU's reasonable  satisfaction,  NYU shall
          have the right,  upon written notice to  CORPORATION,  solely at NYU's
          discretion,  either to  terminate  this  Agreement  or to convert  the
          License granted herein to a non-exclusive license.

     f.   CORPORATION shall deliver to NYU a sample of each BPI Product
          developed by CORPORATION promptly after its development. NYU shall use
          such samples only for research purposes and shall not give them to
          others, unless and until such BPI Products are in the public domain or
          unless authorized by CORPORATION in writing.

9.   Payments for License.

     a.   In consideration for the grant of the License  hereunder,  CORPORATION
          shall pay to NYU

                                      -20-

<PAGE>


          (1)  A non-refundable, non-creditable license issue fee of [*] payable
               as follows: [*] on the date that is twenty-four months after the
               Effective Date or upon CORPORATION's first filing of an
               Investigational New Drug ("IND") in the United States with
               respect to the Licensed Products, whichever is earlier; and

          (2)  Non-refundable, milestone payments as follows: [*], which amount
               shall not be creditable against further royalties otherwise
               payable to NYU; and, on [*] of which amount shall be creditable
               against future royalties otherwise payable to NYU; and

          (3)  a royalty of [*] of the Net Sales of any Licensed Product sold by
               CORPORATION or its sublicensees (including CORPORATION Entity)
               for as long as CORPORATION maintains the License except as
               follows in i) and ii) below:

                    (i) If a Licensed Product described in Section 1.1.(aa) or
               (bb) is covered solely by an NYU Patent having

                                      -21-
<PAGE>
               claims directed to the cDNA as described in subparagraph l.e.(iv)
               then the royalty owed by CORPORATION shall be reduced by [*].

                    (ii) If a Licensed Product described in Section 1.1.(aa) or
               (bb) is covered solely by an NYU Patent having claims directed to
               the cDNA as described in subparagraph l.e.(i)(4) and a third
               party is producing and selling a BPI Product by a manufacturing
               process using means other than such claimed cDNA then CORPORATION
               shall have no royalty obligation with respect to such Licensed
               Product.

          (4)  a royalty of [*] of the Net Sales of any Licensed Product
               described in Section 1.1.(cc) or (dd) and sold by COPORATION or
               its sublicensees (including CORPORATION Entity) for as long as
               CORPORATION maintains the License except as follows in i) and ii)
               below:

               (i)  If a Licensed Product in Section 1.1.(cc) or (dd) is covered
                    solely by a CORPORATION Patent having claims directed to the
                    cDNA as described in Section 1.r.(i)(4) then the royalty
                    owed by the CORPORATION to NYU shall be reduced by [*].

               (ii) If a Licensed Product in Section 1.1.(cc) or (dd) is covered
                    solely by an NYU Patent having claims directed to the cDNA
                    as described in Section 1.r.(i)(4) and a third party is
                    producing and selling a P15 Product by a manufacturing
                    process using means other than such

                                      -22-
<PAGE>
                    claimed cDNA then CORPORATION shall have [*] with respect to
                    such Licensed Product.

          (5)  If any Licensed Product is covered solely by a CORPORATION Patent
               then the royalty owed by the CORPORATION to NYU with respect to
               such Licensed Product shall be [*] of the Net Sales of such
               Licensed Product sold by CORPORATION or its sublicensees
               (including CORPORATION Entity) for as long as CORPORATION
               maintains the License.

     b.   For the purpose of computing the royalties due to NYU  hereunder,  the
          year shall be divided  into two parts  ending on June 30 and  December
          31.  CORPORATION  shall,  within  forty-five (45) days from the end of
          each  December and June in each  calendar  year during the term of the
          License,  submit to NYU a full and  detailed  report of  royalties  or
          payments due NYU under the terms of this  Agreement  for the preceding
          half year  (hereinafter  "the  Part-Year  Report"),  setting forth the
          following:

          i)   gross sales of Licensed Products and Combination Products,  i.e.,
               the amount invoiced prior to any deductions,

          ii)  the deductions  permitted under  subsection 1.m. hereof to arrive
               at Net Sales, and

          iii) the royalty computations and subject of payment.

          In determining Net Sales of Combination Products, Net Sales will be
          multiplied by the percent value of BPI Product and/or the P15

                                      -23-
<PAGE>
          Product contained in the Combination Product. Such percent value being
          the quotient obtained by dividing the costs of manufacturing the BPI
          Product and/or the P15 Product by the sum of the cost of the
          manufacturing of the BPI Product and/or the P15 Product plus other
          biologically active ingredients. All such costs of manufacturing shall
          be calculated in accordance with generally accepted accounting
          practices and audited by an independent certified public accountant.
          If no royalties are due, a statement shall be sent to NYU stating such
          fact. The full amount of any royalties or other payments due to NYU
          for the preceding part of the year shall accompany each such report on
          royalties and payments. CORPORATION shall keep and shall cause its
          sublicensees to keep for a period of at least three (3) years after
          the date of entry, full, accurate and complete books and records
          consistent with sound business and accounting practices and in such
          form and in such detail as to enable the determination of the amounts
          due to NYU from CORPORATION pursuant to the terms of this Agreement.

     c.   On reasonable notice and during regular business hours, NYU shall have
          the right to have the books of accounts, records and other relevant
          documentation of CORPORATION or of Corporation Entity inspected by
          independent auditors as set forth herein. If NYU desires to perform
          such audit, NYU shall notify CORPORATION. Within fourteen (14) days
          after receipt of such notice, CORPORATION shall designate one of the
          "Big-6" accounting firms which does not have CORPORATION as a client

                                      -24-
<PAGE>
          and shall notify NYU of CORPORATION's designation and NYU shall engage
          such accounting firm to perform such audit on NYU's behalf. If
          CORPORATION falls to notify NYU of such designated accounting firm
          within such fourteen day period, NYU shall have the right to select
          and engage any accounting firm to perform such audit on NYU's behalf.
          If errors of five percent (5%) or more in NYU's favor are discovered
          as a result of such examination, CORPORATION shall reimburse NYU for
          the expense of such examination. CORPORATION shall undertake to have
          sublicensees of CORPORATION provide audited reports to NYU; if any
          sublicensee does not provide such reports to NYU, CORPORATION shall
          have conducted, at no expense to NYU, an audit of such sublicensee's
          records with respect to the production, marketing and sale of Licensed
          Products and Combination Products every two years, commencing two
          years after the effective date of such sublicensee's agreement with
          CORPORATION.

     d.   If a patent license from a third party is necessary for the
          manufacture or sale of a Licensed Product or Combination Product,
          CORPORATION shall be entitled to deduct from royalties which would
          otherwise be due to NYU under Section 9.a.(3) and/or 9.a.(4) hereof,
          the amount of royalties which CORPORATION must pay to such third party
          for such license. This deduction, however, shall not exceed [*] of the
          royalties otherwise due under this Agreement.

                                      -25-
<PAGE>
     e.   [*]

     f.   In the event that NYU exercises its right to convert the License
          granted herein to a non-exclusive license pursuant to Sections 8.e. or
          9.f., the parties shall negotiate in good faith a reduction of the
          royalties stated in Sections 9.a.(3), 9.a.(4) and 9.e., at a rate
          commensurate with a non-exclusive license effective prospectively from
          the date such negotiated reduction is reduced to writing and signed by
          both parties.

                                      -26-
<PAGE>
     g.   In  the  event  the  License   granted   herein  is   converted  to  a
          non-exclusive  license  pursuant  to  Section  9.e.  and NYU  grants a
          nonexclusive  license to practice the Research  Technology  to a third
          party,  NYU  shall  advise  CORPORATION  as to those  terms  which are
          different in such other license  agreement(s),  whereupon  CORPORATION
          may determine whether such terms are more favorable than those granted
          to CORPORATION.  CORPORATION shall, at its election,  be entitled upon
          written notice to NYU to have this Agreement amended to substitute all
          terms of such more  favorable  license for all terms of this Agreement
          as of the date upon  which  such more  favorable  license  shall  have
          become effective.  Such amendment shall, as to royalty,  apply only to
          prospective royalties.

10. Method of Payment.

     a.   Royalties and any other payments due to NYU hereunder shall be paid to
          NYU in United States dollars. Any royalties and such payments that
          accrue in a foreign currency shall be converted into United States
          dollars based on the closing buying rate of the Morgan Guaranty Trust
          Company of New York applicable to transactions under exchange
          regulations for the particular currency on the last business day of
          the accounting period for which payment is due.

     b.   CORPORATION shall be responsible for payment to NYU of all royalties
          due on sale, transfer or disposition of Licensed Products by the
          sublicensees of CORPORATION.

                                      -27-

<PAGE>


11.  Publication.

     a.   Prior to  submission of  publication  of a manuscript  describing  the
          results  of any  aspect of the NYU  Research  Project,  NYU shall send
          CORPORATION a copy of the manuscript to be submitted,  and shall allow
          CORPORATION  sixty  (60) days from the date of  receipt  to  determine
          whether the  manuscript  contains such subject matter for which patent
          protection  should be sought prior to publication of such  manuscript,
          for the purpose of protecting an invention  made by the NYU Scientists
          during the course  and  within the term of the NYU  Research  Protect.
          Should  CORPORATION  believe  the  subject  matter  of the  manuscript
          contains a patentable invention, then prior to the expiration of sixty
          (60) days from the receipt date of such  manuscript to  CORPORATION by
          NYU,  CORPORATION  shall  give  written  notification  to  NYU  of its
          determination that such manuscript  contains patentable subject matter
          for which patent protection should be sought.

     b.   After the expiration of sixty (60) days from the date of receipt such
          manuscript to CORPORATION, unless NYU has received the written notice
          specified above from CORPORATION, NYU shall be free to submit such
          manuscript for publication to publish the disclosed research results
          in any manner consistent with academic standards.

     c.   Upon  receipt  of such  written  notice  from  CORPORATION,  NYU  will
          thereafter delay submission of the manuscript for an

                                      -28-
<PAGE>
          additional period of up to ninety (90) days to permit preparation and
          filing of U.S. patent application by NYU on the subject matter to be
          disclosed in such manuscript. After expiration of such 90-day period,
          or the filing of a patent application on each such invention,
          whichever shall occur first, NYU shall be free to submit the
          manuscript and to publish the disclosed results.

12.  Infringement of NYU Patent.

     a.   In the event a party to this Agreement acquires information that a
          third party is infringing one or more of the NYU Patents and/or the
          JOINT Patents and CORPORATION Patents, the party acquiring such
          information shall promptly notify the other party to the Agreement in
          writing of such infringement.

     b.   In the event of an  infringement  of the NYU Patents  and/or the JOINT
          Patents,  CORPORATION  shall be  privileged  but not required to bring
          suit against the  infringer,  and to join NYU as a party  plaintiff in
          such suit. Should CORPORATION elect to bring suit against an infringer
          and NYU is joined as a party  plaintiff  in any such  suit,  NYU shall
          have the right to approve  the  counsel  selected  by  CORPORATION  to
          represent  CORPORATION.  The  expenses  of  such  suit or  suits  that
          CORPORATION elects to bring, including any expenses of NYU incurred in
          conjunction  with  the  prosecution  of such  suit  or the  settlement
          thereof,  shall be paid for entirely by  CORPORATION  and  CORPORATION
          shall hold NYU

                                      -29-
<PAGE>
          free, clear and harmless from and against any and all costs of such
          litigation, including attorneys' fees. CORPORATION shall not
          compromise or settle such litigation in which NYU is joined as a party
          plaintiff without the prior written consent of NYU which shall not be
          unreasonably withheld.

     c.   In the event CORPORATION  exercises the right to sue herein conferred,
          it shall  have the  right to first  reimburse  itself  out of any sums
          recovered  in such  suit or in  settlement  thereof  for all costs and
          expenses of every kind and character,  including reasonable attorneys'
          fees, necessarily involved in the prosecution of any such suit, and if
          after such  reimbursement,  any funds shall remain from said recovery,
          CORPORATION shall promptly pay to NYU an amount equal to fifty percent
          (50%) of such remainder and  CORPORATION  shall be entitled to receive
          and  retain  the  balance  of  the  remainder  of  such  recovery.  If
          CORPORATION  is not fully  reimbursed  for the costs and  expenses  of
          litigation  from said  recovery,  CORPORATION  shall have the right to
          deduct from  royalties  otherwise due to NYU, an amount equal to fifty
          percent  (50%) of such  unreimbursed  costs  and  expenses,  provided,
          however,  that such deduction  when combined with any other  deduction
          against  royalties  permitted under this  Agreement,  shall not at any
          time exceed fifty  percent  (50%) of the  royalties  payable to NYU on
          each payment date.

     d.   If CORPORATION does not bring suit against said infringer  pursuant to
          Section 12.b. herein, or has not commenced

                                      -30-
<PAGE>
          negotiations with said infringer for discontinuance of said
          infringement, within 90 days after receipt of such notice, NYU shall
          have the right, but shall not be obligated, to bring suit for such
          infringement and to join CORPORATION as a party plaintiff, in which
          event NYU shall hold CORPORATION free, clear and harmless from and
          against any and all costs and expenses of such litigation, including
          attorneys' fees. If CORPORATION has commenced negotiations with an
          alleged infringer of the NYU Patent and/or the JOINT Patents for
          discontinuance of such infringement within such 90-day period,
          CORPORATION shall have an additional ninety (90) days from the
          termination of such initial 90-day period to conclude its negotiations
          before NYU shall bring suit for such infringement. In the event NYU
          brings suit for infringement of the NYU Patents and/or the JOINT
          Patents, NYU shall have the right to first reimburse itself out of any
          sums recovered in such suit or settlement thereof for all costs and
          expenses of every kind and character, including reasonable attorneys'
          fees necessarily involved in the prosecution of such suit, and if
          after such reimbursement, any funds shall remain from said recovery,
          NYU shall promptly pay to CORPORATION an amount equal to fifty percent
          (50%) of such remainder and NYU shall be entitled to receive and
          retain the balance of the remainder of such recovery.

     e.   Each party shall always have the right to be represented by counsel of
          its own selection in any suit for infringement of

                                      -31-
<PAGE>
          the NYU Patents and/or the JOINT Patents instituted by the other party
          to this Agreement under the terms hereof. The expense of such counsel
          shall be borne by the party initiating such infringement suit.

     f.   CORPORATION  agrees to cooperate fully with NYU at the request of NYU,
          including,  by  giving  testimony  and  producing  documents  lawfully
          requested in the course of a suit  prosecuted by NYU for  infringement
          of the NYU Patents and/or the JOINT Patents provided NYU shall pay all
          reasonable   expenses   (including   attorneys'   fees)   incurred  by
          CORPORATION in connection with such  cooperation.  NYU shall cooperate
          and shall  endeavor  to cause the NYU  Scientists  to  cooperate  with
          CORPORATION  in  the   prosecution  of  a  suit  by  CORPORATION   for
          infringement  of the NYU Patents  and/or the JOINT  Patents,  provided
          that  CORPORATION  shall  pay  all  reasonable   expenses   (including
          attorneys' fees) involved in such cooperation.

     g.   In the event that there is  infringement of the NYU Patents and/or the
          JOINT  Patents on a commercial  scale and neither NYU nor  CORPORATION
          desire to  prosecute  an action for  infringement  and an  independent
          patent attorney  selected upon mutual agreement of NYU and CORPORATION
          recommends  that an action for  infringement  not be brought,  NYU and
          CORPORATION shall negotiate in good faith a reduction to the royalties
          stated  in  Sections  9.a.(3)  and  9.f.,  which  reduction  shall  be
          effective  prospectively,  from the date such negotiated  reduction is
          reduced to writing and signed by both parties.

                                      -32-
<PAGE>
13.  Term and Termination.

     a.   Unless terminated pursuant to this Section 13 or Sections 8.e. or 9.f.
          hereof, this Agreement shall expire on the expiration of the period of
          the License as set forth in Section 7.b. above.

     b.   Six months after the Effective Date, CORPORATION shall have the right
          to terminate this Agreement at any time upon six month's prior written
          notice to NYU

     c.   At any time  prior to  expiration  either  party  may  terminate  this
          Agreement  forthwith for cause by giving  written  notice to the other
          party.  Cause for  termination  of this  Agreement  shall be deemed to
          exist if either NYU or CORPORATION  materially breaches or defaults in
          the  performance  or  observance  of  any of the  provisions  of  this
          Agreement  and such breach or default is not cured  within  sixty (60)
          days or, in the case of  failure  to pay any  amounts  due  hereunder,
          thirty (30) days (unless otherwise  specified herein) after the giving
          of notice by the other party specifying such breach or default,  or if
          either  NYU  or  CORPORATION  discontinues  its  business  or  becomes
          insolvent or bankrupt.

     d.   Upon termination of this Agreement for any reason prior to expiration
          as set forth in Section 13.a. hereof, all rights in and to the
          Research Technology shall revert to NYU, and CORPORATION shall not be
          entitled to make any further use whatsoever of the Research Technology
          and shall not make, use or sell BPI Products and P15 Products.

                                      -33-
<PAGE>
     e.   Upon termination of this Agreement for any reason prior to expiration
          of the License as set forth in Section 13.a., CORPORATION shall
          promptly grant to NYU, without consideration, an exclusive license,
          with the right to sublicense, all of the right, title and interest of
          CORPORATION in and to any JOINT Patents and CORPORATION Patents and
          the provisions of Section 14 shall apply.

     f.   Any amount payable hereunder by one of the parties to the other, which
          has not been paid by its due date of payment  shall bear interest from
          its due date of payment until the date of actual payment,  at the rate
          of two percent  (2%) per annum in excess of the Prime Rate  prevailing
          at the  Citibank,  Inc.,  New York,  New York,  during  the  period of
          arrears  and  such  amount  and the  interest  thereon  may be set off
          against  any  amount  due,  whether  in  terms  of this  Agreement  or
          otherwise, to the party in default by any non-defaulting party.

     g.   Termination of this Agreement shall not relieve the parties of any
          obligation occurring prior to such termination.

     h.   Sections 1, 9, 13, 14, 15, 16, 17.b., and 17.c. hereof shall survive
          and remain in full force and effect after any termination,
          cancellation or expiration of this Agreement.

     14.  CORPORATION's Contingent Right to Royalties.

     Upon termination of this Agreement pursuant to Section 13., the following
provisions shall apply:

                                      -34-
<PAGE>
     a.   NYU and CORPORATION shall continue to file, prosecute and maintain the
          JOINT Patents and NYU and CORPORATION shall share the expenses
          associated with such filing, prosecution and maintenance of such
          patent. NYU shall not abandon NYU Patents and CORPORATION shall not
          abandon CORPORATION Patents without first providing notice and an
          opportunity to the other party to assume prosecution or maintenance of
          such patents.

     b.   NYU shall have the right, but shall not be obligated, to license one
          or more third parties the JOINT Patents and CORPORATION Patents,
          subject to CORPORATION's rights as defined below.

     c.   With respect to any JOINT Patent and/or CORPORATION Patent which NYU
          licenses to a third party, CORPORATION shall be entitled to receive
          [*] of any royalties or other consideration received by NYU and
          attributable to the JOINT Patents and CORPORATION Patent from such
          third party in consideration of a license to practice such Patents.

15. CORPORATION's Indemnification.

     a.   CORPORATION shall, at all times during the term of this Agreement and
          thereafter, defend, indemnify and hold harmless NYU and its trustees,
          officers, agents, employees, faculty and students from and against any
          and all liability, loss, damages and expenses (including attorneys'
          fees), they may suffer as the result of claims, demands, costs or
          judgments which may be made or

                                      -35-
<PAGE>
          instituted against them or any of them arising out of the manufacture,
          distribution, use, testing, sale or other disposition by CORPORATION
          or any Corporation Entity, distributor, customer, sublicensee or
          representative of CORPORATION or anyone in privity therewith, of any
          BPI Products, or any method or process licensed by NYU to CORPORATION
          hereunder or out of any representation made by CORPORATION pursuant to
          Section 19 of this Agreement. CORPORATION's obligation to defend,
          indemnify and hold harmless shall include, but not be limited to,
          claims, demands, costs or judgments, whether for money damages or
          equitable relief by reason of: alleged personal injury (including
          death) to any person; alleged property damage; alleged infringement of
          any United States or foreign patent, copyright or other proprietary
          rights. b. NYU agrees to notify CORPORATION as soon as NYU becomes
          aware of a claim or action for which indemnification may be sought
          pursuant to this Section 15. At NYU's request, CORPORATION shall
          provide attorneys to defend against any claim or action with respect
          to the subject of indemnity contained herein, whether or not such
          claims are rightfully brought or filed.

16.  Security for Indemnification.

     a.   CORPORATION shall not sell any BPI products nor manufacture, have
          manufactured, market or distribute, any BPI Products for commercial
          sale, nor grant any rights to

                                      -36-
<PAGE>
          a third party to sell BPI Products or to make, have made, distribute
          or market any BPI Products for commercial sale unless CORPORATION
          shall have first:

          i)   provided NYU with a certificate of insurance proving the
               CORPORATION or such third party has in force, during the term of
               this Agreement, a policy of insurance acceptable to NYU which:

               (a)  is drawn in an amount not less than five million dollars
                    ($5,000,000) for each occurrence as a combined single limit
                    for bodily injury including personal injury and death and
                    property damage; and

               (b)  is endorsed to name NYU, CORPORATION, CORPORATION's
                    sublicensees and their respective partners, trustees,
                    officers, directors, employees, agents and students as
                    additional insureds under such policy of insurance with
                    respect to CORPORATION's obligations to indemnify pursuant
                    to Section 15; and

               (c)  which contains a stipulation that the required coverage will
                    not be reduced, materially altered or cancelled without
                    first giving sixty (60) days prior written notice to NYU's
                    Director of Insurance at NYU; or

                                      -37-
<PAGE>
          ii)  provided NYU written evidence acceptable to NYU (at the
               individual full discretion of NYU) that CORPORATION has
               sufficient financial resources to support meaningfully the
               indemnification obligations undertaken in Section 15; or

          iii) provided NYU with CORPORATION's warranty and representation (and
               upon request by NYU, evidence acceptable to NYU) that
               CORPORATION's net worth (excluding intangible assets) during the
               term of this Agreement is in excess of five million dollars
               ($5,000,000), as determined in accordance with accounting
               principles generally accepted in the United States and
               consistently applied; or

          iv)  provided NYU, with a written guarantee and undertaking in form
               satisfactory, on a reasonable basis, to NYU by a party having
               sufficient financial resources to support the indemnification
               obligations undertaken in Section 15. Such party shall be
               required to execute in form satisfactory, on a reasonable basis,
               to NYU a guarantee and undertaking to:

               (a)  provide  defense  and  indemnification  to NYU  pursuant  to
                    Section 15 hereof;

               (b)  maintain  at all times  required  by  Section  16.b.  hereof
                    sufficient  insurance or  self-insurance  to  indemnify  NYU
                    pursuant to Section 15;

               (c)  upon written

                                      -38-
<PAGE>
                    request of NYU provide evidence satisfactory, on a
                    reasonable basis, to NYU that such party maintains such
                    insurance or self-insurance, and (d) appoint an agent for
                    service of process in the United States and consent to
                    jurisdiction in the federal and state courts of New York.
                    With respect to such third parties in each instance, NYU and
                    CORPORATION shall negotiate in good faith to determine the
                    nature and extent of the financial resources necessary to
                    constitute "sufficient financial resources" for purposes of
                    this Section 16.a.(iv).

     b.   Unless waived in writing by NYU, CORPORATION agrees that the liability
          insurance policy or policies referred to in Section 16.a. above shall
          be maintained in force for so long as this Agreement remains in force
          and for six (6) years thereafter or as long as CORPORATION or such
          third party shall make, use or sell BPI Products, and for six (6)
          years thereafter, whichever shall be longer. Neither CORPORATION nor
          any third party shall terminate, reduce the face value of, or
          otherwise materially modify such insurance coverage during the
          aforementioned period of time, unless equal or greater coverage is
          provided under another policy in compliance with the foregoing
          provisions and without a gap in coverage.

                                      -39-
<PAGE>
17.  Confidential Information.

     a.   Except as otherwise provided in Section 11 above and in Section 17.c.
          below, NYU shall maintain any and all of the Research Technology and
          the JOINT Patents in confidence and shall not release or disclose any
          tangible or intangible component thereof to any third party without
          first receiving the prior written consent of CORPORATION to said
          release or disclosure.

     b.   Except as provided in Section 17.c. below CORPORATION shall maintain
          any and all of the Research Technology and the JOINT Patents in
          confidence and shall not release or disclose any tangible or
          intangible component thereof to any third party without first
          receiving the prior written consent of NYU to said release or
          disclosure.

     c.   The obligations of confidentiality  set forth in Sections 17.a. and b.
          shall not apply to any  component of the Research  Technology  and the
          JOINT  Patents  which  is  part  of the  public  domain  prior  to the
          Effective Date of this Agreement or which becomes a part of the public
          domain  not  due  to  some  unauthorized  act  by or  omission  of the
          receiving party after the Effective Date of this Agreement or which is
          disclosed to the receiving party by a third party who has the right to
          make such disclosure.

     d.   The provisions of Section 17.b. notwithstanding, CORPORATION may
          disclose the Research Technology and the JOINT Patents to third
          parties who need to know the same in order to secure Regulatory
          Approval for the sale of Licensed Products.

                                      -40-
<PAGE>
18.  Representation and Covenants.

     a. CORPORATION hereby represents and warrants to NYU as follows:

          i)   CORPORATION is a corporation duly organized, validly existing and
               in good standing under the laws of the State of Delaware.
               CORPORATION has been granted all requisite power and authority to
               carry on its business and to own and operate its properties and
               assets. The execution, delivery and performance of this Agreement
               have been duly authorized by the Board of Directors of
               CORPORATION.

          ii)  There is no pending or threatened litigation involving
               CORPORATION which would have any effect on this Agreement or on
               CORPORATION's ability to perform its obligations hereunder; and

          iii) There is no indenture, contract, or agreement to which
               CORPORATION is a party or by which CORPORATION is bound which
               prohibits or would prohibit the execution and delivery by
               CORPORATION of this Agreement or the performance or observance by
               CORPORATION of any term or condition of this Agreement.

     b. NYU hereby represents and warrants to CORPORATION as follows:

               i) Subject to Sections  4.c. and 5.c.  above,  NYU has the entire
          right,  title and  interest  in and to the NYU Patents  identified  on
          Appendix I;

               ii) NYU does not own or control any patent or patent application
          which covers the making, using or selling

                                      -41-
<PAGE>
          of BPI Product and/or Combination  Product other than as identified on
          Appendix I;

               iii) NYU has not granted any rights to third parties (including
          Genentech, Inc.) in and to the Pre-Existing Inventions, or the BPI
          Products. NYU has obtained from Dr. Peter Elsbach his representation
          that he has not entered into or is not presently a party to an
          agreement with any third party, including Genentech, Inc. relating to
          BPI.

               iv) NYU is a corporation duly organized, validly existing and in
          good standing under the laws of the State of New York. NYU has been
          granted all requisite power and authority to carry on its business and
          to own and operate its properties and assets. The execution, delivery
          and performance of this Agreement have been duly authorized by the
          Board of Trustees of NYU.

19.  No Assignment.

     CORPORATION shall not have the right to assign, delegate or transfer at any
     time to any party, in whole or in part, any or all of the rights, duties
     and interest herein granted without first obtaining the written consent of
     NYU to such assignment, except that CORPORATION shall have the right to
     assign this Agreement subject to all the terms and conditions set forth
     herein to a person or entity which acquires control of CORPORATION.

                                      -42-
<PAGE>
20. Use of Name.

     Without the prior written consent of NYU, CORPORATION shall not use the
     name of NYU or of any NYU staff member, employee or student, or any
     adaptation thereof;

     i)   in any advertising, promotional or sales literature;

     ii)  in connection with any public or private offering or in conjunction
          with any application for regulatory approval, unless disclosure is
          otherwise required by law, in which case CORPORATION may make factual
          statements concerning the Agreement or file copies of the Agreement
          after providing NYU with an opportunity to comment and reasonable time
          within which to do so on such statement in draft.

          Except as provided herein, neither NYU or CORPORATION will issue
          public announcements about this Agreement or the status or existence
          of the NYU Research Project without prior written approval of the
          other party.

                                      -43-
<PAGE>
21. Miscellaneous.

     a.   In carrying out this Agreement the parties shall comply with all
          local, state and federal laws and regulations including but not
          limited to, the provisions of Title 35 United States Code ss.200 et
          seq. and 15 CFR ss.368 et seq.

     b.   If any provision of this Agreement is determined to be invalid or
          void, the remaining provisions shall remain in effect.

     c.   This Agreement shall be governed and interpreted in all respects under
          the laws of the State of  Illinois.  Any  dispute  arising  under this
          Agreement   between  the  parties   requiring   resolution   by  legal
          proceedings  shall be resolved in an action in the state  courts or in
          the federal courts;  if CORPORATION  initiates the legal  proceedings,
          they shall be commenced within the State of New York; if NYU initiates
          the legal  proceedings,  they shall be  commenced  within the State of
          California;  the defendant in either such proceeding shall be entitled
          to bring a  counterclaim  and  join  other  parties  as a part of that
          proceeding.  d. All  payments or notices  required or  permitted to be
          given  under this  Agreement  shall be given in  writing  and shall be
          effective  when either  personally  delivered  or  deposited,  postage
          prepaid, in the United States registered or certified mail,  addressed
          as follows:

                           To NYU:  New York University Medical Center
                                    550 First Avenue
                                    New York, NY 10016
                                    Attention: Isaac T. Kohlberg
                                               Vice President for
                                               Industrial Liaison

                                      -44-
<PAGE>
                                       and

                                     Office of Legal Counsel
                                     New York University
                                     Bobst Library - 11th Floor
                                     70 Washington Square South
                                     New York, NY 10012
                                     Attention: Annette B. Johnson, Esq.
                            Associate General Counsel

                           To CORPORATION:  XOMA CORPORATION
                                            2910 Seventh Street
                                            Berkeley, CA 94710
                                            Attention: Office of the
                                                       Chief Executive Officer

                                       and

                                            XOMA CORPORATION
                                            2910 Seventh Street
                                            Berkeley, CA 94710
                                            Attention: Corporate Secretary

                  or such other address or addresses as either party may
                  hereafter specify by written notice to the other. Such notices
                  and communications shall be deemed to have been received by
                  the addressee on the date of delivery or fourteen (14) days
                  after having been sent by registered mail.

     e.   This Agreement (and the annexed Appendices) constitute the entire
          Agreement between the parties and no variation, modification or waiver
          of any of the terms or conditions hereof shall be deemed valid unless
          made in writing and signed by both parties hereto. This Agreement
          supersedes any and all prior agreements or understandings, whether
          oral or written, between CORPORATION and NYU.

     f.   No waiver by either party of any non-performance or violation by the
          other party of any of the covenants, obligations or agreements of such
          other party hereunder shall be deemed to be a waiver of any subsequent
          violation or non-performance of the same or any other covenant,
          agreement or obligation, nor shall forbearance by any party be deemed
          to be a waiver by such party of its rights or remedies with respect to
          such violation or non-performance.

     g.   The descriptive headings contained in this Agreement are included for
          convenience and reference only and shall not be held to expand, modify
          or aid in the interpretation, construction or meaning of this
          Agreement.

                                      -45-

<PAGE>



     h.   It is not the intent of the parties to create a partnership or joint
          venture or to assume partnership responsibility or liability. The
          obligations of the parties shall be limited to those set out herein
          and such obligations shall be several and not joint.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement the
date and year first above written.

                                NEW YORK UNIVERSITY

                                By: /s/Isaac T. Kohlberg
                                       Isaac T. Kohlberg
                                    Title:   Vice President for
                                             Industrial Liaison
                                Date:    Sept 21st, 1993

                                XOMA CORPORATION

                                By:  /s/Christopher J. Margolin
                                        Christopher J. Margolin
                                     Title:   Vice President and
                                              General Counsel
                                Date:    September 21, 1993

                                      -46-
<PAGE>
                                                                      APPENDIX I


<PAGE>


<TABLE>
<CAPTION>
         Title                                         Serial No.          Date           Priority            Status
<S>      <C>                                           <C>                 <C>            <C>                 <C>
         U.S. Applications

I.       Biologically Active                           07/084,335          8/11/97        None                Abandoned in
         Bactericidal/Permeability                                                                            favor of Ser.
         Increasing Protein                                                                                   No. 07/228,335
         Fragments

II.      Biologically Active                           07/228,035          8/5/88         Ser. No.            Abandoned in
         Bactericidal/Permeability                                                        07/084,335          favor of Ser.
         Increasing Protein                                                                                   No. 07/762,730
         Fragments (C-I-P of Ser.
         No. 084,335)

III.     Biologically Active                           07/762,730          9/17/91        Ser. Nos.           Pending
         Bactericidal/Permeability                                                        07/084,335
         Increasing Protein                                                               and
         Fragments (Continuation                                                          07/228,035
         of Ser. No. 228,035)

IV.      DNA Encoding                                  07/805,031          12/11/91       Ser. Nos.           Issued 3/30/93
         Bactericidal/Permeability                                                        07/084,335          as U.S. Patent
         Increasing Proteins                                                              07/228,035          No. 5,198,541
         (Divisional of Ser. No.                                                          07/762,730
         762,730)

V.       Biologically Active                           07/801,814          12/4/91        Ser. Nos.           Pending
         Bactericidal/Permeability                                                        07/084,335
         Increasing Protein                                                               07/228,035
         Fragments (C-I-P of Ser.                                                         07/762,730
         No. 762,730)

VI.      DNA Encoding                                  08/007,837          1/22/93        Ser. Nos.           Pending
         Bactericidal/Permeability                                                        07/084,335
         Increasing Proteins                                                              07/228,035
         (Continuation of Ser. No.                                                        07/762,730
         805,814)                                                                         07/801,814

         Foreign Applications

         Canada                                        07/574,398          8/11/87        Ser. Nos.           Pending
                                                                                          07/084,335
                                                                                          07/228,035

         PCT National and Regional Phase

         European Patent                               88907884.6          2/9/90         Ser. Nos.           Pending
                                                                                          07/804,335
                                                                                          07/228,035

         Japan                                         507146/88           8/9/88         Ser. Nos.           Pending
                                                                                          07/804,335
                                                                                          07/228,035
</TABLE>
<PAGE>
                                                            APPENDIX I (Cont'd.)

<TABLE>
<CAPTION>
         Title                                         Serial No.          Date           Priority            Status
<S>      <C>                                           <C>                 <C>            <C>                 <C>
         U.S. Applications

I.       Biologically Active                           07/621,473          12/3/90        Ser. Nos.           Abandoned in
         Bactericidal/Permeability                                                        07/084,335          favor of Ser.
         Increasing Protein                                                               07,228,035          No. 754,204
         Fragments (C-I-P of Ser.                                                         07/502,560
         No. 228,035 and
         502,560)

II.      Biologically Active                           07/754,204          8/26/91        Ser. Nos.           Pending
         Bactericidal/Permeability                                                        07/084,335
         Increasing Protein                                                               07/228,035
         Fragments (C-I-P of Ser.                                                         07/502,560
         No. 621,473)                                                                     07/621,473

         PCT National and Regional Phase

         European Patent                               92902215.0          6/3/93         Ser. Nos.           Pending
           France                                                                         07/804,335
           Germany                                                                        07/228,035
           United Kingdom                                                                 07/506,560
</TABLE>
<PAGE>
                                                                     APPENDIX II

<TABLE>
<CAPTION>
         Title                                         Serial No.          Date           Priority            Status
<S>      <C>                                           <C>                 <C>            <C>                 <C>
         U.S. Applications

I.       Polypeptides that                             07/502,560          3/30/90                            Abandoned in
         Potentiate                                                                                           favor of
         Bactericidal/Permeability                                                                            Ser. No.
         Increasing Protein and                                                                               07/767,551
         Methods for Treating
         Bacterial Infections

II.      Polypeptides that                             07/767,551          9/26/91        Ser. No.            Abandoned in
         Potentiate                                                                       07/502,560          favor of
         Bactericidal/Permeability                                                                            Ser. No.
         Increasing Protein and                                                                               07/905,066
         Methods for Treating
         Bacterial Infections
         (Continuation of Ser. No.
         07/502,560)

III.     Polypeptides that                             07/905,066          6/24/92        Ser. Nos.           Abandoned in
         Potentiate                                                                       07/502,560          favor of
         Bactericidal/Permeability                                                        07/767,551          Ser. No.
         Increasing Protein and                                                                               08/023,760
         Methods for Treating
         Bacterial Infections
         (C-I-P of Ser. No.
         07/767,551)

IV.      Polypeptides that                             08/023,760          2/26/93        Ser. Nos.           Pending
         Potentiate                                                                       07/502,560
         Bactericidal/Permeability                                                        07/767,551
         Increasing Protein and                                                           07/905,066
         Methods for Treating
         Bacterial Infections
         (C-I-P of Ser. No.
         07/905,066)
</TABLE>


<PAGE>


                                                                  APPENDIX III-A

               Amended and Restated Research and License Agreement
                  Elsbach/Weiss Research Project for Years 1-3

Objectives:

         [*]
                                        1
<PAGE>

         [*]

                                        2
<PAGE>

         [*]
                                        3
<PAGE>
                                                                  APPENDIX III-B

                      NYU RESEARCH PROJECT - FOR YEARS 4-6

         [*]

                                        4
<PAGE>

         [*]
                                        5
<PAGE>

         [*]
                                        6
<PAGE>

         [*]
                                        7
<PAGE>

         [*]
                                        8
<PAGE>

         [*]
                                        9


<PAGE>
                                                                     APPENDIX IV

               Amended and Restated Research and License Agreement
                                Development Plan

         [*]

                                       10
<PAGE>

         [*]
                                       11
<PAGE>
                                                                      Appendix V

                                    NYU/XOMA
               AMENDED AND RESTATED RESEARCH AND LICENSE AGREEMENT
                            RESEARCH PAYMENT SCHEDULE

     XOMA shall pay NYU for work performed on the NYU Research Project during
the fourth through six years of the Research Period the total of [*] in six
installments of [*] each.

     The first such payment shall be due within fifteen (15) days after the
signature of this Agreement by the last party to sign ("the Execution Date").
Subsequent payments shall be made every six months after the Execution Date
until the total of [*] is paid.

     XOMA may retain [*] of each payment until XOMA receives the written six
month research report provided in accordance with Section 3.c.








AMD\NYU.210

[*] indicates that a confidential portion of the text of this agreement has been
omitted and filed separately with the Securities and Exchange Commission

                      THIRD AMENDMENT TO LICENSE AGREEMENT

     This Third Amendment to License Agreement (hereinafter the "Amendment "),
is made and effective on June 12, 1997, by and between XOMA CORPORATION, a
corporation organized and existing under the laws of the State of Delaware and
having a place of business at 2910 Seventh Street, Berkeley, California 94710
(hereinafter "CORPORATION"), and NEW YORK UNIVERSITY, a corporation organized
and existing under the laws of the State of New York and having a place of
business at 70 Washington Square South, New York, New York, 10012 (hereinafter
"NYU").

     WHEREAS, CORPORATION and NYU have entered into a certain agreement (the
"Agreement") made and effective as of August 6, 1990 (the "Effective Date"), as
amended and restated on September 1, 1993, pursuant to which, inter alia,
CORPORATION undertook to sponsor the NYU Research Project (as such term is
defined in the Agreement) and NYU granted to CORPORATION the License (as such
term is defined in the Agreement); and

     WHEREAS, CORPORATION and NYU wish to amend and extend the Agreement under
certain terms as specified herein;

     NOW, THEREFORE, in consideration of the premises and the covenants,
conditions and promises set forth below, the parties hereto hereby agree as
follows:

1.   Except as expressly provided for herein, all terms and conditions of the
     Agreement shall remain in full force and effect.

2.   Terms which are defined in the Agreement shall have the same meanings when
     used in this Amendment, unless a different definition is given herein.

3.   The second line of Subsection 1.d. of the Agreement shall be, and hereby
     is, amended to read as follows:

     BPI that NYU had in its possession on the Effective Date

4.   The first line of Subsection 1.e.i) of the Agreement shall be, and hereby
     is, amended to read as follows:

     any product for therapeutic or prophylactic use.

5.   The first line of Subsection 1.r.i) shall be, and hereby is, amended to
     read as follows:

     any product for therapeutic or prophylactic use.

6.   Section  1.v.  of the  Agreement  shall be, and  hereby is,  amended in its
     entirety so that, as amended, said Section 1.v. shall read as follows:


<PAGE>


     v. "Research Period" shall mean the eight (8) year period commencing upon
     the Effective Date and any extension thereof as to which NYU and
     CORPORATION shall mutually agree in writing.

7.   Section  4.a.  of the  Agreement  shall be, and  hereby is,  amended in its
     entirety so that, as amended, said Section 4.a. shall read as follows:

     a. As compensation to NYU for work performed on the NYU Research Project
     during the Research Period, CORPORATION shall pay NYU (i) the sum of [*]
     payable in accordance with the Schedule annexed to the Agreement as
     Appendix V, which forms an integral part thereof; NYU acknowledges that as
     of June 12, 1997, CORPORATION has paid NYU this amount in full; and (ii)
     the sum of [*] in two equal, consecutive, semi-annual installments, the
     first of which shall be due on or before August 31, 1997.

8.   The ninth line of Subsection 9.a.(l) of the Agreement shall be, and hereby
     is, amended by adding a comma and the following language after the word
     earlier and before the semicolon:

     [*]

9.   The ninth line of Subsection 9.a.(2) of the Agreement shall be, and hereby
     is, amended by adding the following language after the word and:

     [*]

10.  The third line of Subsection 9.a.(3) of the Agreement shall be, and hereby
     is, amended by adding the following language after the word Entity):

     [*]

                                        2


<PAGE>


     [*]

11.  The third line of Subsection 9.a.(4) of the Agreement shall be, and hereby
     is, amended by adding the following language after the word Entity):

     [*]

12.  The sixth line of Subsection 9.a.(5) of the Agreement shall be, and hereby
     is, amended by adding the following language after the word Entity):

     [*]

13.  The second line of Subsection 9.e. of the Agreement shall be, and hereby
     is, amended by the addition of the following language after the word
     "Product" and the deletion of the comma after such word:

     for any human diagnostic, prophylactic or therapeutic use

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
follows:

NEW YORK UNIVERSITY                                  XOMA CORPORATION

By:      /s/ Isaac T. Kohlberg              By:      /s/Christopher J. Margolin
         Isaac T. Kohlberg                           Christopher J. Margolin
         Associate Dean and Vice                     Vice President, General
         President for Industrial                    Counsel and Secretary
         Liaison

Date: 6/20/97                                        Date: 6/17/97




                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS


     As independent public accountants, we hereby consent to the incorporation
of our reports included in this Form 10-K into the Company's previously filed
Registration Statements on Form S-3 (File Nos. 333-02493, -07263, -34907 and
33-59379) and on Form S-8 (33-39155).

San Francisco, California                              ARTHUR ANDERSEN LLP
March 18, 1998





                                       44

<TABLE> <S> <C>


<ARTICLE>                                       5
       
<S>                                                                                                  <C>
<PERIOD-TYPE>                                                                                       YEAR
<FISCAL-YEAR-END>                                                                           Dec-31-1997
<PERIOD-END>                                                                                Dec-31-1997
<CASH>                                                                                            37,225
<SECURITIES>                                                                                      17,921
<RECEIVABLES>                                                                                          0
<ALLOWANCES>                                                                                           0
<INVENTORY>                                                                                            0
<CURRENT-ASSETS>                                                                                  55,639
<PP&E>                                                                                            30,478
<DEPRECIATION>                                                                                    25,914
<TOTAL-ASSETS>                                                                                    64,776
<CURRENT-LIABILITIES>                                                                              8,763
<BONDS>                                                                                                0
<COMMON>                                                                                              20
                                                                                  0
                                                                                            0
<OTHER-SE>                                                                                        31,220
<TOTAL-LIABILITY-AND-EQUITY>                                                                      64,776
<SALES>                                                                                                0
<TOTAL-REVENUES>                                                                                  18,383
<CGS>                                                                                                  0
<TOTAL-COSTS>                                                                                          0
<OTHER-EXPENSES>                                                                                  35,552
<LOSS-PROVISION>                                                                                       0
<INTEREST-EXPENSE>                                                                                1,101
<INCOME-PRETAX>                                                                                  (15,765)
<INCOME-TAX>                                                                                           0
<INCOME-CONTINUING>                                                                              (15,765)
<DISCONTINUED>                                                                                         0
<EXTRAORDINARY>                                                                                        0
<CHANGES>                                                                                              0
<NET-INCOME>                                                                                     (15,765)
<EPS-PRIMARY>                                                                                      (0.44)
<EPS-DILUTED>                                                                                      (0.44)
        


</TABLE>


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