ADVANCED TISSUE SCIENCES INC
8-K, 1998-01-27
BIOLOGICAL PRODUCTS, (NO DIAGNOSTIC SUBSTANCES)
Previous: MENTORTECH INC, DEF 14A, 1998-01-27
Next: SEAFIELD CAPITAL CORP, 8-K, 1998-01-27



                                       


                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549


                                   FORM 8-K

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


                                CURRENT REPORT

  Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934


                               JANUARY 14, 1998
                                Date of Report
                       (Date of earliest event reported)


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


                        ADVANCED TISSUE SCIENCES, INC.
            (Exact name of registrant as specified in its charter)



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

         Delaware                      0-016607                 14-1701513
         --------                      --------                 ----------
(State or other jurisdiction of      (Commission             (I.R.S. Employer
 incorporation or organization)       File No.)             Identification No.)


10933 North Torrey Pines Road, La Jolla, California               92037
- ---------------------------------------------------               -----
     (Address of principal executive offices)                   (Zip Code)


      Registrant's telephone number, including area code:  (619) 450-5730




<PAGE>

Item  5.    Other  Events

On January 14, 1998, Advanced Tissue Sciences, Inc. (the "Company" or
"Advanced Tissue Sciences") entered into a binding letter of intent (the
"Heads of Agreement") to expand its fifty-fifty joint venture with Smith &
Nephew plc ("Smith & Nephew") to include venous ulcers, pressure sores, burns
and other skin wounds.  The joint venture (the "Dermagraft Joint Venture") was
originally formed in April 1996 for the worldwide commercialization of
Dermagraft(R), the Company's tissue engineered dermal skin replacement, for 
the treatment of diabetic foot ulcers.  The Heads of Agreement expands the
Dermagraft Joint Venture to include the worldwide development and marketing of
Dermagraft for the treatment of venous ulcers and pressure sores and the
marketing of Dermagraft-TC(TM) outside the United States.  The Company 
retains the exclusive right, and will continue to market, Dermagraft-TC as a 
temporary covering for full and partial thickness burns, while the Dermagraft 
Joint Venture has the right to market Dermagraft-TC for other skin wounds, in 
the United States.

Under the Heads of Agreement, Smith & Nephew has purchased $20 million, or
1,533,115 newly-issued shares, of the Company's Common Stock at approximately
$13.05 per share.  In addition to the equity investment, Smith & Nephew will
pay the Company $15 million upon the earlier of (i) U.S. Food and Drug
Administration ("FDA") approval for the marketing of Dermagraft in the
treatment of diabetic foot ulcers or (ii) January 4, 1999.  In addition to the
milestones under the joint venture agreement completed in 1996, the Company
could also receive up to $76 million on the achievement of certain milestones
related to product approvals and payor reimbursement, and based on worldwide
product sales.  Including the $20 million equity investment and a $10 million
up front fee paid to the Company by Smith & Nephew when the Dermagraft Joint
Venture was formed in 1996, payments to the Company by Smith & Nephew in
connection with the joint venture could potentially total up to $181 million
subject to the achievement of certain milestones.  No assurance can be given 
that the Dermagraft Joint Venture or the Company will receive FDA approvals 
or successfully commercialize products which are the subject of the 
Dermagraft Joint Venture or that adequate levels of payor reimbursement for 
such products will be available.  Accordingly, no assurance can be given that 
the Company will receive any or all of the milestone payments referred to 
above.

Advanced Tissue Sciences and Smith & Nephew will continue to share equally in
the expenses and revenues of the Dermagraft Joint Venture except, as provided
in the Heads of Agreement, Advanced Tissue Sciences will fund the first $6
million of expenses for conducting clinical trials and for regulatory support
of Dermagraft and Dermagraft-TC in the treatment of ulcers and pressure sores.
The Company will also continue to manufacture and sell Dermagraft, and now
Dermagraft-TC, to the Dermagraft Joint Venture at cost.

The Heads of Agreement and the related Common Stock Purchase Agreement dated
January 14, 1998 between the Company and Smith & Nephew are attached hereto as
exhibits and incorporated herein by reference.  The foregoing is qualified in
its entirety by reference to such exhibits.



Item  7.    Exhibits
            --------

 Exhibit
  Number                    Description
 -------                    -----------

  10.1      Heads of Agreement Dated January 14, 1998 between Advanced Tissue
            Sciences, Inc. and Smith & Nephew plc

  10.2      Common Stock Purchase Agreement, Dated January 14, 1998, between
            Advanced Tissue Sciences, Inc. and Smith & Nephew SNATS, Inc.



<PAGE>


                                  SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.




                                         ADVANCED TISSUE SCIENCES, INC.


Date:  January 27, 1998                  By:  /s/ Arthur J. Benvenuto
                                            --------------------------
                                            Arthur J. Benvenuto
                                            Chairman and Chief Executive  
                                            Officer

<PAGE>


                                 EXHIBIT INDEX


 Exhibit
 Number                     Description                                 Page
 -------                    -----------                                 ----

  10.1       Heads of Agreement Dated January 14, 1998 between 
             Advanced Tissue Sciences, Inc. and Smith & Nephew plc

  10.2       Common Stock Purchase Agreement, Dated January 14, 
             1998, between Advanced Tissue Sciences, Inc. and 
             Smith & Nephew SNATS, Inc.







                                                                Exhibit 10.1


                              HEADS OF AGREEMENT
                       Expanded Dermagraft Joint Venture


     This Agreement is entered into effective as of January 14, 1998, by and
between Advanced Tissue Sciences, Inc., a Delaware corporation ("ATS"), and
Smith & Nephew plc, a company organized under the laws of the United Kingdom
("S&N"), together with their respective Affiliates (ATS Dermagraft, Inc., a
California corporation, and Smith & Nephew SNATS, Inc., a Delaware
corporation), with respect to the following facts:


                                   RECITALS

     A.  ATS and S&N, through their Affiliates, have entered into certain
agreements, dated as of April 29, 1996, as follows:

         1.  Agreement of General Partnership of Dermagraft U.S., a Delaware
general partnership (the "U.S. Partnership Agreement").

         2.  Agreement of General Partnership of Dermagraft International, a
Delaware general partnership (the "International Partnership Agreement").

         3.  U.S. License Agreement (the "U.S. License Agreement").

         4.  International License Agreement (the "International License
Agreement").

         5.  U.K. License Agreement (the "U.K. License Agreement").

         6.  DermEquip, L.L.C. Agreements.

For convenience of reference, the above-referenced agreements collectively
shall be referred to as the "Dermagraft Agreements".

     B.  Certain capitalized terms used in this Agreement are defined to have
the meaning as specified on Exhibit A attached hereto and made a part hereof.
Other capitalized terms used in this Agreement are defined in the Dermagraft
Agreements.

     C.  The Dermagraft Agreements involve the development, manufacture,
marketing and sale of Dermagraft  for the treatment of diabetic foot ulcers
(the "Subject Product").

     D.  As further described in this Agreement, ATS and S&N desire to expand
the scope of the Dermagraft Agreements (i) to add Subject Wound Care
Applications for Dermagraft (in 


<PAGE>


addition to diabetic foot ulcers), (ii) to include the ATS product known as 
Dermagraft-TC (TM) for Subject Wound Care Applications, and (iii) to add Future
Products.

     E.  The parties intend this Agreement to be binding and enforceable on
the parties in accordance with the terms of this Agreement.  The parties
understand and intend that amendments to or restatements of the Dermagraft
Agreements will be prepared subsequently for approval and signature by both
parties and their Affiliates, in order to further implement the parties'
agreements as set forth in this Agreement.


     WHEREFORE, the parties hereto mutually agree to the following principal
terms and agreements:

     1.     S&N Purchase of ATS Stock.
            -------------------------
            a.   S&N (directly or through an Affiliate) hereby agrees to 
purchase from ATS, and ATS hereby agrees to sell to S&N (directly or through 
an Affiliate), approximately 1,538,461 shares of ATS common stock (the 
"Shares") [assuming $13.00 per share price], for an aggregate cash purchase 
price of $20 million, payable in cash within three (3) business days after 
the signing by both ATS and S&N of this Agreement.  The exact number of the 
Shares shall be determined by dividing into $20 million the average of the 
last reported sale price per share of the ATS common stock on the Nasdaq 
National Market for the nine trading days ending on the date of this 
Agreement, using the last sale price for each of said nine days for determining
the average per share price.  ATS and S&N each warrants and agrees for itself 
and its Affiliates and directors and senior executives that they have not 
bought, sold or otherwise traded any ATS shares since December 22, 1997 to the 
date hereof, and that they have not done anything else outside the ordinary 
course of business for the purpose of affecting said closing sale prices for 
said nine trading days.

            b.   Promptly after the receipt by ATS of said $20 million cash 
purchase price, ATS shall cause to be issued to S&N (or its Affiliate) a share
certificate evidencing the Shares.  The Shares will not be registered with the
U.S. Securities and Exchange Commission ("SEC"), and the Shares will be
subject to applicable securities law restrictions on the transfer and sale of
the Shares.

            c.   S&N (or its Affiliate) represents that it is purchasing the 
Shares for its own investment account.  S&N (or its Affiliate) agrees that it 
will not sell the Shares prior to the "Permitted Sale Date", which shall be 
the earlier of (i) a Material Default by ATS or its Affiliates under the 
Dermagraft Agreements, (ii) thirty (30) months after the date hereof, or 
(iii) the occurrence of one or more of the specific material changes 
specified on Exhibit B attached hereto, and then only after dissemination to 
the public of information regarding such occurrence(s).  After the Permitted 
Sale Date, S&N (or its Affiliate) will be entitled to sell on the public market 
any or all of the Shares only after the Shares have been registered with the 
SEC, provided that after the Permitted Sale Date, and after two business days 
prior written notice to ATS, the Shares may be sold by S&N (or its Affiliate) 
pursuant to SEC Rule 144, in lieu of 

                                  -2-

<PAGE>

being sold pursuant to a registration statement.  S&N (or its Affiliate) shall 
have one customary "demand registration right" pursuant to which ATS shall use 
diligent efforts to register the Shares and keep the registration statement 
effective until the Shares have been sold by S&N (or its Affiliate), and S&N 
(or its Affiliate) shall have customary "piggy back registration rights", 
subject to the customary underwriter's cut-back provision based upon market 
demands for ATS Shares.  At such time as S&N (or its Affiliate) is permitted 
to sell some of the Shares, S&N (or its Affiliate) shall coordinate any 
public market sale through an underwriting firm which is reasonably 
acceptable to ATS.

            d.   S&N hereby acknowledges (i) that it is an "accredited 
investor" within the meaning of Regulation D under the Securities Act of 1933, 
and (ii) that it has such knowledge and experience in financial and business 
matters that it is capable of evaluating, and that it has had the opportunity 
to evaluate, the merits and risks of its investment in the Shares.

            e.   ATS hereby represents and warrants that its most recent 
Annual Report on Form 10-K and most recent Quarterly Report on Form 10-Q as 
filed with the SEC do not, as of their respective filing dates, contain any 
untrue statement of material fact or omit to state a material fact required 
to be stated therein or necessary to make the statements therein not 
misleading.  S&N acknowledges receipt of a copy of ATS' most recent annual 
report and quarterly report filed by ATS with the SEC.

            f.   ATS and S&N will enter into a customary Stock Purchase 
Agreement to evidence this sale and purchase of the Shares.

     2.     Expanded Field of Use.  The Dermagraft Agreements shall be
            ---------------------
modified to accomplish an expansion of the field of use for the ATS Technology
to include uses for the treatment of the Subject Wound Care Applications.

     3.     Expanded Products.
            -----------------
            a.   The Dermagraft Agreements shall be modified to accomplish an
expansion of the products covered by the Dermagraft Agreements (to expand
beyond the Dermagraft product) to include the Dermagraft-TC product for use
for treatment of the Subject Wound Care Applications.  The product name for
the Dermagraft-TC product shall be changed worldwide by mutual agreement to a
different name (e.g., "TransCyte").

            b.   Additionally, the Dermagraft Agreements shall be modified to 
accomplish an expansion of the products covered by the Dermagraft Agreements 
to include all Future Products for which the U.S. Partnership (and/or the 
International Partnership) pays all of the future costs to develop, and ATS 
shall not be entitled to receive any additional milestone payments for the 
addition of such Future Products.  The U.S. Partnership and the International 
Partnership shall have the first priority right to develop and commercially 
exploit each proposed Future Product.

                                 -3-

<PAGE>


            c.   With respect to any Excluded Product for which ATS pays the 
costs of development, ATS shall be entitled to receive additional milestone 
payments if such Excluded Product is later added to the Dermagraft Agreements.
Additionally, ATS (and its Affiliates) shall comply with the provisions in
Section 8.6.2(c) of the U.S. Partnership Agreement if the Excluded Product is
also a Competitive Product.

     4.     Marketing and Sales.
            -------------------
            a.   Pursuant to the Dermagraft Agreements, and as part of the 
business of the U.S. Partnership and the International Partnership, 
Affiliates of S&N have exclusive responsibilities and rights for marketing and 
selling the Subject Product (Dermagraft used for diabetic foot ulcers) on a 
worldwide basis.  The same shall be true for the expanded fields of use for 
Dermagraft as set forth in Section 2 hereof for the Subject Wound Care 
Applications, and for the Future Products which are added to the Dermagraft 
Agreements.  The same shall also be true for the Dermagraft-TC product which 
is being added to the Dermagraft Agreements pursuant to Section 3 hereof, for 
the Subject Wound Care Applications, except as specified in Section 4b 
hereof.  All of such marketing and selling activities shall be conducted in 
accordance with, and subject to, the terms of the Dermagraft Agreements, as 
amended.

            b.   ATS (or its designated Affiliates) shall retain the exclusive 
right to market and distribute the Dermagraft-TC product for partial and full 
thickness burns in the United States.  Until changes are made pursuant to 
Section 10 hereof, the Dermagraft-TC product shall be manufactured by ATS (or 
its Affiliate) and then sold and supplied to the International Partnership 
and/or the U.S. Partnership, at a transfer price that reflects the full cost 
of manufacture.  Once changes are made pursuant to Section 10 hereof for the 
U.S. Partnership (and/or the International Partnership) to acquire 
manufacturing equipment and facilities from ATS, then the U.S. Partnership 
(and/or the International Partnership) shall manufacture the Dermagraft-TC 
product, and other fibroblast-based products, to be sold and supplied to ATS 
(or its Affiliates) at a transfer price that reflects, at a minimum, the full 
cost of manufacture.

     5.     Milestones.  S&N (or an Affiliate of S&N) will pay or cause to be
            ----------
paid to ATS (or an Affiliate of ATS if so designated by ATS) either directly
or through the Dermagraft Partnerships created by the U.S. Partnership
Agreement and the International Partnership Agreement, the following milestone
payments:

            a.   $15 million cash on the earlier of (i) January 4, 1999, or 
(ii) within five days after S&N receives documentary confirmation from ATS 
that a PMA approval has been granted for selling Dermagraft for diabetic foot 
ulcers in the United States.

            b.   $3 million cash within five days after S&N receives 
documentary confirmation from ATS that a PMA approval has been granted for 
selling Dermagraft for venous ulcers in the United States.

            c.   $3 million cash within five days after S&N receives 
documentary confirmation from ATS of Medicare Coverage for the use of 
Dermagraft for venous ulcers.

                                 -4-

<PAGE>


            d.   $5 million cash within five days after S&N receives 
documentary confirmation from ATS that a PMA approval has been granted for 
selling Dermagraft for pressure ulcers consistent with the patient population 
covered by the protocol of the clinical trial (which shall include a majority 
of patients with full thickness, stage III pressure ulcers).
 
            e.   $5 million cash within five days after S&N receives 
documentary confirmation from ATS of Medicare Coverage for the use of 
Dermagraft for pressure ulcers.

            f.   $10 million cash within thirty days after S&N receives 
documentary confirmation from ATS that the net sales of Dermagraft-TC for 
pressure ulcers for any consecutive twelve-month period has reached $50 
million.

            g.   The existing milestone payments schedule set forth in the 
Dermagraft Agreements provide, in general, for a $10 million milestone 
payment when worldwide annual sales within any consecutive twelve-month period 
(a "12-Month Period") of the Subject Product reach $100 million, and for an 
additional $10 million milestone payment each time such sales for a 12-Month 
Period are increased by another $100 million, for up to $50 million of 
milestone payments when $500 million of worldwide sales for a 12-Month Period 
are achieved.  Said milestone payment schedule shall be modified to provide 
that when the worldwide sales for a 12-Month Period for the Subject Product 
and the Expanded Products reach $50 million, then a $5 million milestone 
payment shall be made, with an additional $5 million milestone payment each 
time worldwide sales for a 12-Month Period are increased by another $50 
million for the Subject Product and the Expanded Products, up to a maximum of 
$100 million of milestone payments when the worldwide sales for a 12-Month 
Period of the Subject Product and the Expanded Products have reached $1 
billion.  The calculation of said worldwide sales for a 12-Month Period shall 
include the aggregate, combined total Net Sales (as defined in the Dermagraft 
Agreements) of the aggregate of the Subject Product and the Expanded 
Products, made worldwide to third parties and/or to end users, by the U.S. 
Partnership, the International Partnership, S&N and their Affiliates and 
sublicensees, during any twelve consecutive months, but excluding ATS sales 
in the United States for Dermagraft-TC as specified in Section 4(b) hereof.  
At the election of S&N, the required milestone payments may be allocated and 
paid by S&N (and its Affiliates) via the U.S. Partnership and the 
International Partnership.

            h.   The existing milestone payments in the Dermagraft Agreements 
(i) for $5 million for a PMA approval for Dermagraft for diabetic foot 
ulcers, and (ii) for $5 million for Medicare Coverage for Dermagraft for 
diabetic foot ulcers, shall remain in effect and be payable as stated in the 
Dermagraft Agreements.

     6.     Funding Expenses for Clinical Trials.  With respect to the
            ------------------------------------
expenses for conducting clinical trials and related regulatory support for the
use of Dermagraft and/or Dermagraft-TC, for the treatment of venous ulcers and
pressure ulcers indications, ATS (or its Affiliates) shall provide the cash
funds and bear the expense to pay the first $6 million of these expenses
incurred from and after January 1, 1998.  Said $6 million of expenses shall be
specially allocated to ATS as an expense for accounting and tax reporting
purposes.  In calculating said expenses, all reasonable and preagreed direct
and indirect costs shall be included and aggregated, 

                                 -5-

<PAGE>


including general overhead costs reasonably and appropriately allocated for 
conducting and supporting said clinical trials and related regulatory 
support.  All additional such expenses beyond the initial $6 million for 
conducting said clinical trials shall be borne by the U.S. Partnership and 
the International Partnership, with the Affiliates of ATS and S&N each bearing 
a one-half share through said partnerships.

     7.     First Negotiation Rights.
            ------------------------
            a.   The parties acknowledge that gene therapy/delivery 
applications for the Dermagraft product and/or the Dermagraft-TC product 
constitute Excluded Applications and are not covered by this Agreement or the 
Dermagraft Agreements.  ATS hereby grants to S&N a first right of negotiation
with respect to any commercial or technical exploitation (including a sale, 
partial sale, or partnering arrangement) which ATS (or its Affiliates or 
sublicensees) may develop or pursue with respect to gene therapy/delivery 
applications for the ATS Technology applicable for any Wound Care Applications 
(except for Excluded Products).  S&N shall have a ninety-day right of first 
negotiation with respect thereto, commencing upon S&N receiving a written 
notice (the "First Rights Notice") from ATS specifying in general terms (i) 
the nature of the transaction, (ii) the structure of transaction and (iii) 
the financial terms which ATS is willing to consider.  This first right of 
negotiation shall be for S&N to negotiate to pursue said gene 
therapy/delivery applications in a venture with ATS (and not independent of 
ATS) in a manner similar to the Dermagraft Agreements, or in such other 
manner as may be mutually approved by both parties.

            b.   ATS shall not enter into any such commercial or technical 
exploitation agreement with a third party for gene therapy/delivery 
applications for the ATS Technology applicable for any Wound Care Applications 
(except for Excluded Products) on terms more favorable to the third party than 
were the terms specified by ATS in the most recent First Rights Notice given 
to S&N.

     c.     ATS shall not give the First Rights Notice to S&N and ATS shall 
not enter into any third party agreement as referenced in Section 7(b) hereof
until after thirty (30) months following the date hereof.

     8.     Competitive Products.  The definition of "Competitive Product" in
            --------------------
the Dermagraft Agreements (e.g., at Section 8.6.2(c) of the U.S. and
International Partnership Agreements) and this Agreement shall be revised to
read as follows with respect to the Expanded Products only (the definition
with respect to the Subject Product shall not change):

     "Competitive product" for Expanded Products shall mean a 
     product (excluding Existing S&N Products) which is likely 
     to be in competition with the Expanded Products, and 
     "competition" for this purpose shall mean a biologically 
     active product, excluding growth factors, growth factor 
     substitutes, cytokines, enzymes, enzyme inhibitors, agents 
     for gene therapy, established or new synthetic chemical 
     entities, bio-materials and bio-material composites, and
     also excluding any "Updated Existing S&N 

                                 -6-

<PAGE>

     Products" (as defined on Exhibit A-1 attached hereto), used 
     in the treatment of the Subject Wound Care Applications
     (excluding diabetic foot ulcers)."

     9.     Failure to Commercialize.  In addition to any other rights of ATS
            ------------------------
under any of the Dermagraft Agreements, in the event that S&N (or its
Affiliates) fails to use commercially reasonable efforts to pursue the
material components of the Business Plan for the U.S. Partnership and the
International Partnership, and such failure materially adversely affects the
business of the Partnerships, and which failure shall continue for a period of
six (6) months after written notice thereof from ATS, then ATS and S&N shall
mutually implement a cessation of the U.S. Partnership and the International
Partnership in accordance with Section 12.4.4 of the respective partnership
agreements (Mutual Cessation of Operations).

     10.    Business Reorganization.  In order to more efficiently operate
            -----------------------
and manage the expanded business of the International Partnership and the U.S.
Partnership with respect to the Expanded Products, as contemplated by this
Agreement, the parties shall pursue good faith discussions and analysis for
establishing revised organizational, operational, management, and facilities
structures, with a goal of having the business operations of the U.S.
Partnership and the International Partnership become closer to a "free
standing" business unit by no later than July 1, 1999.  In this regard, the
parties shall consider transferring for value the facilities and equipment
used for the manufacture of the Dermagraft product and the Dermagraft-TC
product into said free standing business unit.

     11.    Press Release.  Promptly following the execution of this Agreement
            -------------
by the parties, ATS and S&N shall each issue a press release substantially 
in the form as approved by both ATS and S&N.

     12.    Implementing Documents.  The parties will pursue good faith
            ----------------------
negotiations and analysis to enter into amendments to the existing Dermagraft
Agreements, in order to implement and to carry out the purposes and intentions
of this Agreement.  In the meantime, any conflict or inconsistencies between
the terms of this Agreement and the terms of the Dermagraft Agreements shall
be controlled by the terms of this Agreement.

     13.    Governing Law.  This Agreement shall be construed and enforced in
            -------------
accordance with the laws of the State of Delaware.

     14.    Arbitration.  Any disputes arising with respect to this Agreement
            -----------
shall be resolved through binding arbitration by a single, qualified
arbitrator selected from a list of three candidates furnished by the President
of the Health Industry Manufacturing Association ("HIMA").  If the President
of HIMA is unwilling or unable to provide a list of candidates, the candidates
shall be proposed by the American Arbitration Association ("AAA"), Chicago,
Illinois, from its Complex Dispute Panel.  The arbitration proceedings shall
be conducted in accordance with the then current Commercial Rules of
Arbitration of the AAA, or in accordance with such other rules or procedures
as the arbitrator may specify.  If the parties do not promptly select an
arbitrator, the 

                                 -7-

<PAGE>


arbitrator shall be selected by AAA.  The arbitration shall take place in
Chicago, Illinois, U.S.A.  Each party shall bear all of its own arbitration
expenses, plus one-half of the arbitrator's fee.

     IN WITNESS WHEREOF, the parties have executed and delivered this
Agreement as of the date set forth above.

                         ADVANCED TISSUE SCIENCES, INC.

                              By: ____________________________________


                         SMITH & NEPHEW plc

                              By: ____________________________________


                         ATS DERMAGRAFT, INC.

                              By: ____________________________________


                         SMITH & NEPHEW SNATS, INC.

                              By: ____________________________________


                                 -8-

<PAGE>

                                  EXHIBIT  A
                                  Definitions


     "12-Month Period" means a period of any twelve consecutive months.

     "Affiliate" means (i) any entity directly or indirectly controlling, 
controlled by, or under common control with another entity, (ii) any person 
or entity owning or controlling 50% or more of the outstanding voting 
securities of an entity, or (iii) any officer, director or partner of an 
entity.  "Control" means the possession of the power to direct or cause the 
direction of the management and the policies of an entity, whether through 
the ownership of a majority of the outstanding voting securities or by contract
or otherwise.

     "ATS Technology" means ATS patented technology and related technology,
know-how, methods, procedures and licenses for developing and selling cell
based and/or tissue engineered, three-dimensional tissues on biocompatible
matrices, to the extent said technology is useful for the Subject Wound Care
Applications.  The patent rights from which the ATS Technology is derived are
listed on Exhibit B attached to the U.S. License Agreement.  The ATS
Technology shall include all U.S. divisions, continuations, reissues and
extensions which are derived from the patents and patent applications
pertaining to the technology, patents and applications listed on said Exhibit
B.  The ATS Technology available for use pursuant to this Agreement is limited
to the Subject Wound Care Applications.

     "Dermagraft(R)" means the ATS dermal tissue replacement product which is
formulated through the ATS Technology.

     "Dermagraft Agreements" means the agreements described in Recital A above.

     "Dermagraft-TC(TM)" means the ATS human fibroblast-derived temporary skin
substitute product which is formulated through the ATS Technology.

     "Excluded Applications" means the use of ATS Technology (including 
Dermagraft and/or Dermagraft-TC) for (i) injectible collagen, (ii) gene 
therapy/delivery, (iii) dental applications, (iv) cosmetic surgery for the 
enhancement of normal tissue (but not the treatment of skin tissue defects or 
post-surgical or post-trauma skin tissue rehabilitation), and (iv) ostomy 
applications.

     "Excluded Products" means Future Products for which both the U.S. Partner-
ship and the International Partnership decides to decline to pay the future 
costs to develop, and ATS then pays the costs to develop.

     "Expanded Products" means (i) the Dermagraft product used for treatment
of all Subject Wound Care Applications, except for diabetic foot ulcers, and
(ii) the Dermagraft-TC product used for treatment of all Subject Wound Care
Applications, and (iii) Future Products.

                                 -9-

<PAGE>

     "First Rights Notice" is defined in Section 7 hereof.

     "Future Products" means all products (beyond the Dermagraft product and
the Dermagraft-TC product) developed from the ATS Technology for use in the
Subject Wound Care Applications, including products already in the course of
development as of the date hereof (other than Excluded Products).

     "Medicare Coverage" means that the product is reimbursable by the United
States Medicare program, following the general concepts as specified in the
Dermagraft Agreements to the extent applicable.

     "Permitted Sale Date" is defined in Section 1(c) hereof.

     "PMA" means a Pre-Market Approval application submitted to the United 
States Food and Drug Administration.

     "SEC" is defined in Section 1(b) hereof.

     "Subject Product" means Dermagraft used for the treatment of diabetic 
foot ulcers.

     "Subject Wound Care Applications" means all Wound Care Applications 
except for the Excluded Applications and the Excluded Products.

     "Wound Care Applications" means applications of the ATS Technology 
(e.g., Dermagraft, Dermagraft-TC and Future Products) for the medical care and
treatment of skin tissue wounds on humans.  Without limiting the generality of
the foregoing, Wound Care Applications includes diabetic ulcers, pressure
ulcers, venous ulcers, burns (partial thickness and full thickness), cosmetic
surgery for skin tissue defects or post-surgical or post-trauma skin tissue
rehabilitation (but not cosmetic surgery for the enhancement of normal skin
tissue (e.g., chemical peels and laser resurfacing) and ostomy applications.

                                 -10-


<PAGE>

                                  EXHIBIT A-1
                                  (Section 8)

                         Updated Existing S&N Products


     1.  Those Existing S&N Products as defined in the U.S. Partnership
Agreement at Section 8.6.2(c).

     2.  Those products which S&N and its Affiliates (i) currently are selling
as of January 14, 1998, as more fully described on Schedule 1 to be delivered
to ATS within the next 30 days, or (ii) as of January 14, 1998, have been the
subject of an active research and development project, as demonstrated by
historical laboratory, clinical, developmental, financial or other records of
S&N and its Affiliates.

                                 -11-


<PAGE>

                                  EXHIBIT  B

                        Definition of Material Changes
                                 (Section 1c)


     1.  ATS publicly announces a proposed merger of ATS with another company,
pursuant to which the former shareholders of ATS will own less than 75% of the
combined voting equity of the merged entity.

     2.  ATS sells its voting equity stock to a party such that the party (and
its Affiliates) owns more than 25% of all of the ATS voting equity stock.

     3.  ATS sells a component or components of the ATS business over a
rolling 12-month period for consideration in excess of 33% of the total ATS
market capitalization at the time of the public announcement of the sale.  (A
licensing transaction for a strategic alliance in which ATS will continue to
be involved is not a sale for purposes of this section.)

     4.  The termination of either Arthur J. Benvenuto or Gail K. Naughton as
executives of ATS, without a mutually acceptable replacement executive being
hired by ATS, with S&N's acceptance (or disapproval) to be given based upon
S&N's good faith and reasonable discretion.

     5.  The share price for ATS common stock falls below $6.00 for two
consecutive days, as shown on last reported sale for the day on the Nasdaq
National Market.

     6.  The ATS Board of Directors decides, and makes a public announcement
of said decision, to make a fundamental change in the business of ATS such
that ATS' focus is no longer principally in the area of human tissue
engineered products.











                                 COMMON STOCK
                              PURCHASE AGREEMENT


                        ADVANCED TISSUE SCIENCES, INC.
                                      AND
                          SMITH & NEPHEW SNATS, INC.


                               JANUARY 14, 1998


<PAGE>


                               TABLE OF CONTENTS
                               -----------------
                                                                       Page
                                                                       ----
SECTION 1.   Purchase and Sale of Stock                                  1
     1.1   Sale and Purchase of the Shares                               1
     1.2   Closing                                                       1

SECTION 2.   Representations and Warranties of the Company               1
     2.1   SEC Filings                                                   1
     2.2   Absence of Certain Changes                                    2
     2.3   Organization, Good Standing and Qualification                 2
     2.4   Authorization                                                 2
     2.5   Capitalization                                                2
     2.6   Valid Issuance of Stock                                       3
     2.7   Governmental Consents                                         3
     2.8   Litigation, etc.                                              3
     2.9   Subsidiaries                                                  3
    2.10   No Conflict with Other Instruments                            3
    2.11   Patents, Trademarks and Regulatory Approvals                  3

SECTION 3.   Purchaser Representations and Warranties                    4
     3.1   Authorization                                                 4
     3.2   Purchase Entirely for Own Account                             4
     3.3   Disclosure of Information                                     5
     3.4   Investment Experience                                         5
     3.5   Restricted Securities                                         5
     3.6   Further Limitations on Disposition                            5
     3.7   Legends                                                       5

SECTION 4.   Registration Rights                                         6
           Definitions                                                   6
     4.1   Demand Rights                                                 6
           (a)  Registration                                             6
           (b)  Underwriting                                             6
           (c)  Limitations                                              7
     4.2   PiggyBack Rights                                              7
          (a)   Notice of Registration                                   7
          (b)   Underwriting                                             8
     4.3  Obligations of the Company                                     8
     4.4  Furnish Information                                           10
     4.5  Expenses of Company Registration                              10
     4.6  Indemnification                                               10
     4.7  Reports Under Securities Exchange Act of 1934                 12
     4.8  Assignment of Registration Rights                             12
     4.9  Amendment of Registration Rights                              12
     4.10 Termination of Registration Rights                            12

                                   i

<PAGE>

                               TABLE OF CONTENTS
                               -----------------
                                                                       Page
                                                                       ----

SECTION 5.  Covenants                                                   13
     5.1  Limitation on Sale of Stock                                   13
     5.2  Permitted Transfer                                            13

SECTION 6.   Miscellaneous                                              13
     6.1  Survival of Warranties                                        13
     6.2  Successors and Assigns                                        13
     6.3  Governing Law                                                 13
     6.4  Counterparts                                                  13
     6.5  Titles and Subtitles                                          14
     6.6  Assignment                                                    14
     6.7  Notices                                                       14
     6.8  Finder's Fee                                                  15
     6.9  Expenses                                                      15
     6.10 Amendments and Waivers                                        15
     6.11 Severability                                                  15
     6.12 Aggregation of Stock                                          16





          EXHIBIT A
              Schedule of Exceptions (Section 2)
          EXHIBIT B
              Definition of Material Changes (Section 5.1)

                                   ii

<PAGE>


                             INDEX TO DEFINITIONS
                             --------------------
                                                                     Section
                                                                     -------
     Act                                                               1.2

     Affiliate                                                         4.8

     Agreement                                                        Intro.

     Effective Date                                                   Intro.

     Closing                                                           1.2

     Company                                                          Intro.

     Dermagraft Agreements                                             5.1

     Exchange Act                                                     4.6(a)

     Heads of Agreement                                                5.1

     Holder                                                             4

     Non-participating Holders                                        4.2(b)

     Permitted Sale Date                                               5.1

     Purchase Price                                                    1.1

     Purchaser                                                        Intro.

     Register, Registered, and Registration                             4

     Registrable Securities                                             4

     Registration Expenses                                             4.5

     Schedule of Exceptions                                     2 & Exhibit A

     SEC                                                               1.2

     SEC Filings                                                        2

     Subject Wound Care Applications                                  2.11

     Stock                                                             1.1

     Violation                                                       4.6(a)

                                   i

<PAGE>

                                 COMMON STOCK
                              PURCHASE AGREEMENT


     THIS COMMON STOCK PURCHASE AGREEMENT (this "Agreement") is made as of
January 14, 1998 (the "Effective Date") by and between Advanced Tissue
Sciences, Inc., a Delaware corporation (the "Company"), and Smith & Nephew
SNATS, Inc., a Delaware corporation (the "Purchaser").

     THE PARTIES HEREBY AGREE AS FOLLOWS:

SECTION 1.   Purchase and Sale of Stock
             --------------------------

             1.1  Sale and Purchase of the Shares.  Pursuant to the terms 
                  -------------------------------
hereof and in reliance upon the representations and agreements contained 
herein, at the Closing (as hereinafter defined), the Company will issue and 
sell to Purchaser, and Purchaser will purchase from the Company, US 
$20,000,000 (the "Purchase Price") of the Company's Common Stock, $0.01 par 
value (the "Stock").  The aggregate number of shares of Stock which the 
Purchaser shall purchase shall be _______________________________________, at 
a per share price of $______________.

             1.2  Closing.  Payment for and delivery of the Stock shall take 
                  -------
place at a closing to be held at the offices of the Company three (3) 
business days after the Effective Date (which time and place are designated 
as the "Closing").  At the Closing the Company shall deliver to Purchaser a 
certificate representing the Stock against payment to the Company of the 
Purchase Price by Purchaser by bank wire transfer of immediately available 
funds to an account designated by the Company payable to the Company's order.  
The Stock will not be registered with the U.S. Securities and Exchange 
Commission ("SEC") under the U.S. Securities Act of 1933, as amended (the 
"Act") unless and until registration occurs pursuant to Section 4 hereof.

SECTION 2.   Representations and Warranties of the Company.  Subject to and
             ---------------------------------------------
except as disclosed in the SEC Filings (defined in Section 2.1 hereof) and/or
in the Schedule of Exceptions attached hereto as Exhibit A, the Company hereby
represents and warrants to Purchaser that as of the Effective Date:

             2.1  SEC Filings.  The Company has previously furnished to 
                  -----------
Purchaser true and complete copies (with material exhibits) of the Company's 
(i) Annual Report on Form 10-K for the fiscal year ended December 31, 1996 
(the "1996 Annual Report"); (ii) Quarterly Reports on Form 10-Q for the 
quarters ended March 31, 1997, June 30, 1997 and September 30, 1997 (the 
"Quarterly Reports"); (iii) proxy statements relating to all meetings of its
stockholders (whether annual or special) since December 31, 1996; (iv) all 
other reports and registration statements (except registration statements on 
Form S-8) filed by the Company with the SEC 

<PAGE>

since December 31, 1996; and (v) audited financial statements for the fiscal 
years ended and as of December 31, 1994, 1995 and 1996.  As of their 
respective dates, the SEC Filings (as hereinafter defined) did not contain 
any untrue statement of a material fact or omit to state a material fact 
required to be stated therein or necessary to make the statements therein, 
in light of the circumstances under which they were made, not misleading.  
Since December 31, 1996, the Company has filed with the SEC all reports and 
registration statements and all other filings required to be filed with the 
SEC under the rules and regulations of the SEC.  The audited financial 
statements and unaudited interim financial statements of the Company included
or incorporated by reference in the 1996 Annual Report and the Quarterly 
Reports, respectively, have been prepared in accordance with generally 
accepted accounting principles applied on a consistent basis (except as may 
be indicated therein or in the notes thereto, and with respect to the 
unaudited interim financial statements, except as to normal year-end auditing
adjustments and the absence of notes) and fairly present the financial 
position of the Company and its subsidiaries as at the dates thereof and the 
results of their operations, cash flows and changes in financial position for
the periods then ended.  As used in this Agreement, "SEC Filings" means the 
reports, registration statements, proxy statements and audited financial 
statements of the Company referred to in clauses (i) through (v) of the first
sentence of this Section 2.1.

             2.2  Absence of Certain Changes.  Except as set forth in the SEC 
                  --------------------------
Filings and/or the Schedule of Exceptions, since December 31, 1996, there has 
not been any material adverse change, outside the ordinary course of 
business, in the assets, condition, affairs or prospects of the Company and 
its subsidiaries, financial or otherwise.

             2.3  Organization, Good Standing and Qualification.  The Company
                  ---------------------------------------------
is a corporation duly organized, validly existing and in good standing under 
the laws of the State of Delaware and has all requisite corporate power and 
authority to carry on its business as now conducted and as currently proposed
to be conducted.  The Company is duly qualified to transact business and is 
in good standing in each jurisdiction in which the failure so to qualify 
would have a material adverse effect on its business, properties or financial
condition.

             2.4  Authorization.  This Agreement constitutes a valid and 
                  -------------
legally binding obligation of the Company, enforceable against the Company in
accordance with its terms.  The Company has all the requisite corporate power
and is duly authorized to execute and deliver this Agreement, and all 
corporate actions on the part of the Company, its officers, directors and 
stockholders necessary for the authorization, execution and delivery of this 
Agreement and consummation of the transactions contemplated hereby have been 
taken.

             2.5  Capitalization.  The authorized capital stock of the 
                  --------------
Company consists of 100,000,000 shares of Common Stock, of which 37,674,983* 
shares are issued and outstanding, as of the Effective Date, and 1,000,000 
shares of Preferred Stock, of which no shares are issued and outstanding as 
of the Effective Date.  All such issued and outstanding shares have been duly
authorized and validly issued, and are fully paid and non-assessable.  Except
as set forth in notes to the SEC Filings, there are no preemptive or other 
outstanding rights, options, warrants, conversion rights or agreements for 
the purchase or acquisition from the Company of any shares

                                   2

<PAGE>


of its capital stock or other securities of the Company.  All of the
outstanding shares of Common Stock and the Preferred Stock have been duly and
validly issued in compliance with federal and state securities laws.

             2.6  Valid Issuance of Stock.  The Stock, when issued, sold and 
                  -----------------------
delivered in accordance with the terms hereof for the consideration expressed
herein, will be duly authorized and validly issued, fully paid and non-
assessable and, based in part upon the representations of Purchaser in this 
Agreement, will be issued in compliance with all applicable federal and state
securities laws.

             2.7  Governmental Consents.  No consent, approval, order or 
                  ---------------------
authorization of, or registration, qualification, designation, declaration or
filing with, any federal, state or local governmental authority on the part 
of the Company is required in connection with the consummation of the 
transactions contemplated by this Agreement, except for notices required or 
permitted to be filed with Nasdaq, the SEC and with certain state securities 
commissions after the Closing, which notices will be filed on a timely basis.
 
             2.8  Litigation, etc.  There is no action, suit, proceeding or 
                  ---------------
investigation, pending or threatened, (i) which questions the validity of 
this Agreement or any other agreement contemplated hereby or the right of the
Company to enter into such agreements, or (ii) which might result, either 
individually or in the aggregate, in any material adverse change in the 
assets, condition, affairs or prospects of the Company and its subsidiaries, 
financial or otherwise, or (iii) which is against the Company or any employee
or officer of or consultant to the Company or any of its subsidiaries, by 
reason of the past employment or consulting relationships of any employee, 
officer or consultant of the Company.

             2.9  Subsidiaries.  The Company does not presently own or 
                  ------------
control, directly or indirectly, and has no stock or other interest as owner 
or principal in, any other corporation or partnership, joint venture, 
association or other business venture or entity, other than as listed
on the Schedule of Exceptions.

             2.10  No Conflict with Other Instruments.  The execution, 
                   ----------------------------------
delivery and performance of this Agreement will not result in any violation 
of, be in conflict with, or constitute a default under, with or without the 
passage of time or the giving of notice:  (i) any provision of the Company's 
Certificate of Incorporation or By-laws; (ii) any provision of any judgment, 
decree or order to which the Company or any of its subsidiaries is a party or
by which it is bound; (iii) any material contract, obligation or commitment 
to which the Company or any of its subsidiaries is a party or by which it is 
bound; or (iv) to the Company's knowledge, any statute, rule or governmental 
regulation applicable to the Company or any of its subsidiaries.

             2.11  Patents, Trademarks and Regulatory Approvals.
                   --------------------------------------------
The Company owns or has sufficient rights in the ATS Technology and the 
Dermagraft(R) trademark, free and clear of any liens or encumbrances, to 
conduct the business of the Company as contemplated by the 

                                   3

<PAGE>


Dermagraft Agreements and the Heads of Agreement (as referenced in Section 
5.1 hereof).  The Company is not aware of any existing or threatened 
infringement action or claim of invalidity or adverse ownership with respect 
to the ATS Technology and the Dermagraft(R) trademark for use in conjunction 
with the Subject Wound Care Applications (as defined in the Heads of 
Agreement) or of any facts which indicate that any such action or claim is 
likely to be instituted or asserted.  The Company has disclosed to Purchaser 
or its Affiliates all relevant information known to the Company and believed 
by the Company to be significant and requested by Purchaser or its Affiliates
concerning the Company's efforts to obtain regulatory approvals for the 
Subject Wound Care Applications products.  The Company has not knowingly 
withheld any significant relevant information known to the Company which the 
Company believes Purchaser would reasonably want to know concerning the 
Company's efforts to obtain regulatory approvals for the Subject Wound Care 
Applications products.  In seeking regulatory approvals, the Company has not 
knowingly submitted to any regulatory body any material information regarding
the Subject Wound Care Applications products which is known to the Company to
be false or misleading, and the Company has not knowingly omitted to submit 
to any regulatory body any information known to the Company to be necessary 
to make submitted information not misleading.  Purchaser understands, 
however, that the ATS Technology involves technologies which have not been 
approved by any regulatory agency (other than an approval of the 
Dermagraft-TC product for specified uses in the United States and Dermagraft 
for specified uses in Canada), and that the Company cannot guarantee the 
safety or usefulness of any Subject Wound Care Applications products.

             THE COMPANY MAKES NO WARRANTIES OTHER THAN AS SET FORTH IN THIS 
SECTION 2.11 CONCERNING THE ATS TECHNOLOGY, INCLUDING WITHOUT LIMITATION, THE 
COMPANY MAKES NO EXPRESS OR IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS 
FOR A PARTICULAR PURPOSE.  EXCEPT AS SET FORTH IN THIS SECTION 2.11, THE 
COMPANY MAKES NO WARRANTY OR REPRESENTATION AS TO THE VALIDITY OR SCOPE OF THE 
ATS TECHNOLOGY PATENT RIGHTS, OR THAT ANY PRODUCT WILL BE FREE FROM AN 
INFRINGEMENT ON PATENTS OF THIRD PARTIES, OR THAT NO THIRD PARTIES ARE IN ANY
WAY INFRINGING ATS TECHNOLOGY PATENT RIGHTS.

SECTION 3.   Purchaser Representations and Warranties.  Purchaser hereby
             ----------------------------------------
represents and warrants as of the Effective Date:

             3.1  Authorization.  This Agreement constitutes a valid and 
                  -------------
legally binding obligation of Purchaser, enforceable against Purchaser in 
accordance with its terms.  Purchaser has all the requisite corporate power 
and is duly authorized to execute and deliver this Agreement, and all 
corporate action on the part of the Purchaser, its officers, directors and 
stockholders necessary for the authorization, execution and delivery of this 
Agreement and the consummation of the transactions contemplated hereby has 
been taken.

             3.2  Purchase Entirely for Own Account.  This Agreement is made 
                  ---------------------------------
with Purchaser in reliance upon Purchaser's representation to the Company, 
which by such Purchaser's 

                                   4

<PAGE>


execution of this Agreement Purchaser confirms, that the Stock to be received by
Purchaser will be acquired for investment for Purchaser's own account, not as
a nominee or agent, and not with a view to the resale or distribution of any
part thereof, and that Purchaser has no present intention of selling or
granting any participation in, or otherwise distributing the same.  By
executing this Agreement, Purchaser further represents that Purchaser does not
have any contract, undertaking, agreement or arrangement with any person to
sell, transfer or grant participation to such person or to any third person,
with respect to any of the Stock.  Purchaser understands that the Stock to be
purchased by it has not been registered under the Act by reason of a specific
exemption from the registration provisions of the Act which depends upon,
among other things, the bona fide nature of Purchaser's investment intent as
expressed herein.

             3.3  Disclosure of Information.  Purchaser has had an 
                  -------------------------
opportunity to ask questions of the Company regarding the terms and 
conditions of the private placement of the Stock and has received 
satisfactory answers to all such questions.  The foregoing, however, does not
limit or modify the representations and warranties of the Company in Section 
2 of this Agreement.

             3.4  Investment Experience.  Purchaser is an "accredited 
                  ---------------------
investor" as defined in Rule 501(a) promulgated under the Act.  Purchaser is 
able to bear the economic risk of its investment in the Company, including 
the entire loss of such investment.  Purchaser has such knowledge and 
experience in financial and business matters that it is capable of evaluating
the merits and risks of the investment in the Stock, and Purchaser has had 
the opportunity to evaluate the merits and risks of its investment in the 
Stock.

             3.5  Restricted Securities.  Purchaser understands that the 
shares of Stock, when issued and sold pursuant to this Agreement, will be 
"restricted securities" under Rule 144 under the Act, and must be held by 
Purchaser indefinitely unless subsequently registered under the Act or an 
exemption from such registration is available.  In this connection, Purchaser 
represents that it is familiar with Rule 144 of the Act as presently in 
effect, and understands the resale limitations imposed thereby and by the Act.

             3.6  Further Limitations on Disposition.  Without in any way 
limiting the representations set forth above, Purchaser agrees not to make 
any disposition of all or any portion of the Stock except in accordance with 
Section 5.1 hereof.

             3.7  Legends.  It is understood that the certificates evidencing 
the Stock may bear one or more of the following legends:  (a) "These 
securities have not been registered under the Securities Act of 1933, as 
amended (the "Act").  They may not be sold, offered for sale, pledged or 
hypothecated in the absence of a registration statement in effect with respect 
to the securities under such Act or an opinion of counsel satisfactory to the 
Company that such registration is not required or unless sold pursuant to 
Rule 144 or 144A of such Act or registration under the Act is unnecessary in 
order for such transfer to comply with the Act."  (b) Anylegend, if any, that 
may be required by the Commissioner of Corporations of the State of 

                                   5

<PAGE>


California or required pursuant to any state, local or foreign laws governing 
such securities.

SECTION 4.   Registration Rights
             -------------------

             Definitions.  For purposes of this Section 4: (a) The term 
             -----------
"register," "registered," and "registration" refer to a registration effected 
by preparing and filing a registration statement or similar document in 
compliance with the Act, and the declaration or ordering of effectiveness of 
such registration statement or document; (b) The term "Registrable Securities" 
means (1) the Stock and (2) any Common Stock of the Company issued as (or 
issuable upon the conversion or exercise of any warrant, right or other 
security which is issued as) a dividend or other distribution with respect to, 
or in exchange for or in replacement of, such Stock, excluding in all cases, 
however, any Registrable Securities sold by a person in a transaction in 
which such person's rights are not derived by assignment under this Section 4; 
(c) The term "Holder" means Purchaser or any assignee thereof in accordance 
with Section 4.8 hereof; (d) The term "Permitted Sale Date" is defined in 
Section 5.1 hereof.
 
             4.1  Demand Rights.
                  -------------
                  (a)   Registration.  After the earlier of the Permitted 
                        ------------
Sale Date or 28 months after the Effective Date, if the Company receives a 
written request from Purchaser that the Company register all of the 
Registrable Securities, then the Company shall:

                        (i)  within ten (10) days after receipt thereof, give 
written notice of such request to all other Holders known to the Company; and

                        (ii) subject to the limitations of Section 4.1 hereof, 
use its diligent efforts to prepare and file with the SEC as soon as 
practicable, and in any event within sixty (60) days after receipt of such 
request, a registration statement under the Securities Act which shall 
include all Registrable Securities which the participating Holders request 
the Company to register pursuant to a written request delivered to the 
Secretary of the Company and received by such Secretary within twenty (20) 
days after the Company mails notice to the other Holders pursuant to 
Section 4.1(a)(i) hereof.

                  (b)   Underwriting.  In connection with a registration 
                        ------------
effected pursuant to this Section 4.1, if the participating Holders intend to 
distribute some or all of the Registrable Securities covered by their 
requests through an underwritten public offering, then the underwriter will 
be selected by the participating Holders and shall be reasonably acceptable 
to the Company.  The participating Holders and the Company shall enter into 
an underwriting agreement in customary form with the selected underwriter.  
If any Holder declines to execute such underwriting agreement, then such 
Holder shall not have any right to include any Registrable Securities in such 
underwriting.  Notwithstanding any other provision of this Section 4.1(b), if 
the underwriter advises the participating Holders and the Company in writing 
that marketing factors require a limitation of the number of shares to be 
underwritten, then the number of shares of Registrable Securities that may be 
included in the underwriting shall be allocated among all of 

                                   6

<PAGE>


the participating Holders thereof, in proportion to the amount of Registrable 
Securities of the Company held by each participating Holder; provided, 
however, that the number of shares of Registrable Securities owned by the 
Holder who initiated the request for the demand registration shall not be 
reduced until all other Holders have been eliminated entirely.  The 
registration statement filed pursuant to the request of the participating
Holders may include other Company securities held by persons with registration
rights and may also include securities of the Company being sold by the
Company for its own account, provided that if more than 50% of the shares sold
in such offering are for the account of the Company, then such registration
shall not be counted for the purpose of the limitation set forth in Section
4.1(c)(ii).

                  (c)   Limitations.  The Company shall not be obligated to 
                        -----------
effect, or to take any action to effect, any registration pursuant to this 
Section 4.1:

                        (i)   In any jurisdiction in which the Company would 
be required to execute a general consent to service of process in effecting 
such registration, qualification, or compliance, unless the Company is already
subject to service of process in such jurisdiction and except as may be
required by the Act.
 
                        (ii)  After the Holders have registered Registrable 
Securities pursuant to this Section 4.1 on one occasion; provided, however, 
that if all of the participating Holders notify the Company in writing that 
they withdraw their request to register their Registrable Securities pursuant 
to this Section 4.1 prior to the filing of the registration statement in 
connection with such registration, and they pay the Registration Expenses 
(as defined below) in connection with such registration, then such 
registration shall not be counted for purposes of this limitation.

                        (iii) At any time during the period beginning when 
the Company has commenced registration procedures (whether by means of 
holding discussions with an underwriter or commencing preparation of the 
registration statement) with respect to the filing of another registration 
statement (other than on Form S-8 or S-4) of the Company with the SEC which 
it in good faith expects to file within thirty (30) days and ending the 
earliest of (A) the abandonment of such other offering; or (B) 180 days after 
the effective date of such other registration statement relating to the other 
offering.

                        (iv)  If the Company shall furnish to the Holders a 
certificate signed by the President of the Company stating that in the good 
faith judgment of the Board of Directors of the Company, it would be 
detrimental to the Company and its stockholders for a registration statement 
to be effected at such time, in which event the Company shall have the right 
to defer the filing of the registration statement for a period of not more 
than 120 days and for not more than once in any 12-month period.

             4.2  PiggyBack Rights.
                  ----------------
                  (a)   Notice of Registration.  Anytime after the Permitted 
                        ----------------------
Sale Date, if 

                                   7

<PAGE>


(but without any obligation to do so) the Company proposes to register 
(including for this purpose a registration effected by the Company for 
stockholders other than the Holders) any of its stock or other securities 
under the Act in connection with the public offering of such securities 
solely for cash (other than a registration relating solely to the sale of 
securities to participants in a Company stock plan), the Company shall, at 
such time, promptly give each Holder written notice of such registration.  
Upon the written request of each Holder given within 20 days after mailing of 
such notice by the Company in accordance with Section 6.7 hereof, the Company 
shall, subject to the provisions of Section 4.2(b) hereof, cause to be 
registered under the Act all of the Registrable Securities that each such 
Holder has requested to be registered.  No Holder shall have any rights under 
this Section 4.2 unless it is the owner of at least 50,000 shares of Common 
Stock.

                  (b)   Underwriting.  If the registration of which the 
                        ------------
Company gives notice is for a registered public offering involving an 
underwriting, the Company shall so advise the Holders as a part of the
written notice given pursuant to this Section 4.2(a) hereof.  In such event,
the right of any Holder to registration pursuant to Section 4.2 shall be
conditioned upon such Holder's participation in such underwriting and the
inclusion of such Holder's Registrable Securities in the underwriting to the
extent provided herein.  All Holders proposing to distribute their securities
through such underwriting shall (together with the Company and the other
Holders distributing their securities through such underwriting) enter into an
underwriting agreement in customary form with the underwriter or
underwriters selected for such underwriting by the Company.  Notwithstanding
any other provision of this Section 4.2, if the underwriter determines that
marketing factors require a limitation of the number of shares to be
underwritten, the underwriter may exclude some or all Registrable Securities
from such registration and underwriting.  The Company shall so advise all
Holders (except those Holders who have indicated to the Company their decision
not to distribute any of their Registrable Securities through such
underwriting) ("Non-participating Holders"), and the number of shares of
Registrable Securities that may be included in the registration and
underwriting shall be allocated among such Holders in proportion, as nearly as
practicable, to the respective amounts of Company securities owned by such
Holders at the time of filing the registration statement; provided, however, 
that all Registrable Securities proposed to be sold for the account of
the Non-participating Holders (or their transferees) shall be excluded from
the registration and underwriting prior to any reduction in the number of
Registrable Securities proposed to be sold for the account of other Holders.
No Registrable Securities excluded from the underwriting by reason of the
underwriter's marketing limitation shall be included in such registration.  If
any Holder disapproves of the terms of any such underwriting, such person may
elect to withdraw therefrom by written notice to the Company and the
underwriter.  The Registrable Securities and/or other securities so withdrawn
from such underwriting shall also be withdrawn from such registration;
provided, however, that, if by the withdrawal of such Registrable Securities a
greater number of Registrable Securities held by other Holders may be included
in such registration (up to the maximum of any limitation imposed by the
underwriters), then the Company shall offer to all Holders who have included
Registrable Securities in the registration the right to include additional
Registrable Securities in the same proportion used above in determining the
underwriter limitation.

                                   8

<PAGE>


             4.3  Obligations of the Company.  Whenever required under this 
                  --------------------------
Section 4 to effect the registration of any Registrable Securities, the 
Company shall, as expeditiously as reasonably possible:

                  (a)   Prepare and file with the SEC a registration statement 
with respect to such Registrable Securities and use its best efforts to cause 
such registration statement to become effective, and, if based upon a demand 
from a Holder,  keep such registration statement effective until all of the 
shares of Stock have been sold.

                  (b)   Prepare and file with the SEC such amendments and 
supplements to such registration statement and the prospectus used in 
connection with such registration statement as may be necessary to comply 
with the provisions of the Act with respect to the disposition of all 
securities covered by such registration statement.

                  (c)   Furnish to the Holders such numbers of copies of a 
prospectus, including a preliminary prospectus, in conformity with the 
requirements of the Act, and such other documents as they may reasonably 
request in order to facilitate the disposition of Registrable Securities 
owned by them.

                  (d)   Use its best efforts to register and qualify the 
securities covered by such registration statement under such other securities 
or Blue Sky laws of such jurisdictions as shall be reasonably requested by 
the Holders, provided that the Company shall not be required in connection 
therewith or as a condition thereto to qualify to do business or to file a 
general consent to service of process in any such states or jurisdictions.

                  (e)   In the event of any underwritten public offering, 
enter into and perform its obligations under an underwriting agreement, in 
usual and customary form, with the managing underwriter of such offering.  
Each Holder participating in such underwriting shall also enter into and 
perform its obligations under such an agreement.

                  (f)   Notify each Holder of Registrable Securities covered 
by such registration statement at any time when a prospectus relating thereto 
is required to be delivered under the Act, of the happening of any event as a
result of which the prospectus included in such registration statement, as
then in effect, includes an untrue statement of a material fact or omits to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading in light of the circumstances then existing.

                  (g)   Furnish, at the request of any Holder requesting 
registration of Registrable Securities pursuant to this Section 4, on the 
date that such Registrable Securities are delivered to the underwriters for 
sale in connection with a registration pursuant to this Section 4, if such 
securities are being sold through underwriters, or, if such securities are 
not being sold through underwriters, on the date that the registration 
statement with respect to such securities becomes effective, (i) an opinion, 
dated such date, of the counsel representing the Company for 

                                   9

<PAGE>


the purposes of such registration, in form and substance as is customarily 
given to underwriters in an underwritten public offering, addressed to the 
underwriters, if any, and to the Holders requesting registration of 
Registrable Securities and (ii) a letter dated such date, from the 
independent certified public accountants of the Company, in form and 
substance as is customarily given by independent certified public accountants 
to underwriters in an underwritten public offering, addressed to the 
underwriters, if any, and to the Holders requesting registration of
Registrable Securities.

             4.4  Furnish Information.  It shall be a condition precedent to 
                  -------------------
the obligations of the Company to a particular selling Holder to take any 
action pursuant to this Section 4 that such selling Holder shall furnish to 
the Company such information regarding itself, the Registrable Securities 
held by it, and the intended method of disposition of such securities as 
shall be required to effect the registration of such selling Holder's 
Registrable Securities.

             4.5  Expenses of Company Registration.  The Company shall bear 
                  --------------------------------
and pay all expenses (the "Registration Expenses") incurred in connection 
with any registration, filing or qualification of Registrable Securities with 
respect to the registrations pursuant to Section 4.1 and 4.2 hereof, 
including (without limitation) all registration, filing and qualification 
fees, printers costs, company attorneys' fees, and accounting fees relating 
or apportionable thereto, and up to $5,000 for the fees and disbursements of 
one counsel for the selling Holders selected by them, but excluding 
underwriting discounts and commissions relating to Registrable Securities.

             4.6  Indemnification.  In the event any Registrable Securities 
                  ---------------
are included in a registration statement under this Section 4:

                  (a)   To the extent permitted by law, the Company will 
indemnify and hold harmless each Holder, the officers and directors of each 
Holder, any underwriter (as defined in the Act) for such Holder and each 
person, if any, who controls such Holder or underwriter within the meaning of 
the Act or the Securities Exchange Act of 1934, as amended (the "Exchange 
Act"), against any losses, claims, damages or liabilities (joint or several) 
to which they may become subject under the Act, the Exchange Act or other 
federal, state and securities' law, insofar as such losses, claims, damages 
or liabilities (or actions in respect thereof) arise out of or are based upon 
any of the following statements, omissions or violations (collectively a 
"Violation"): (i) any untrue statement or alleged untrue statement of a 
material fact contained in such registration statement, including any 
preliminary prospectus or final prospectus contained therein or any 
amendments or supplements thereto, (ii) the omission or alleged omission to 
state therein a material fact required to be stated therein, or necessary to 
make the statements therein not misleading, or (iii) any violation or alleged 
violation by the Company of the Act, the Exchange Act, any state securities 
law or any rule or regulation promulgated under the Act, the Exchange Act or 
any state securities law; and the Company will reimburse each such Holder, 
officer or director, underwriter or controlling person for any legal or other 
expenses as incurred by them in connection with investigating or defending 
any such loss, claim, damage, liability or action; provided, however, that 
the indemnity agreement contained in this subsection 4.6(a) shall 

                                  10

<PAGE>


not apply to amounts paid in settlement of any such loss, claim, damage, 
liability or action if such settlement is effected without the consent of the 
Company (which consent shall not be unreasonably withheld), nor shall the 
Company be liable in any such case for any such loss, claim, damage, 
liability or action to the extent that it arises out of or is based upon a 
Violation which occurs in reliance upon and in conformity with written 
information furnished expressly for use in connection with such registration 
by any such Holder, officer, director, underwriter or controlling person.

                  (b)   To the extent permitted by law, each selling Holder 
will indemnify and hold harmless the Company, each of its directors, each of 
its officers who have signed the registration statement, each person, if any, 
who controls the Company within the meaning of the Act, any underwriter and any
other Holder selling securities in such registration statement or any of its
directors or officers or any person who controls such Holder, against any
losses, claims, damages or liabilities (joint or several) to which the Company
or any such director, officer, controlling person, or underwriter or
controlling person, or other such Holder or director, officer or controlling
person, may become subject, under the Act, the Exchange Act, or other federal
or state law, insofar as such losses, claims, damages or liabilities (or
actions in respect thereto) arise out of or are based upon any Violation, in
each case to the extent (and only to the extent) that such Violation occurs in
reliance upon and in conformity with written information furnished by such
Holder expressly for use in connection with such registration; and each such
Holder will reimburse any legal or other expenses as incurred by the Company
or any such director, officer, controlling person, underwriter or controlling
person, other Holder, officer, director, or controlling person in connection
with investigating or defending any such loss, claim, damage, liability, or
action; provided, however, that the indemnity agreement contained in this
subsection 4.6(b) shall not apply to amounts paid in settlement of any such
loss, claim, damage, liability or action if such settlement is effected
without the consent of the Holder, which consent shall not be unreasonably
withheld; provided, that, in no event shall any indemnity under this
subsection 4.6(b) exceed the gross proceeds from the offering received by such
Holder.

                  (c)   Promptly after receipt by an indemnified party under 
this Section 4.6 of notice of the commencement of any action (including any 
governmental action), such indemnified party will, if a claim in respect 
thereof is to be made against any indemnifying party under this Section 4.6, 
deliver to the indemnifying party a written notice of the commencement 
thereof and the indemnifying party shall have the right to participate in, 
and, to the extent the indemnifying party so desires, jointly with any other 
indemnifying party similarly noticed, to assume the defense thereof with 
counsel mutually satisfactory to the parties; provided, however, that an 
indemnified party shall have the right to retain its own counsel, with the 
fees and expenses to be paid by the indemnifying party, if representation of 
such indemnified party by the counsel retained by the indemnifying party 
would be inappropriate due to actual or potential differing interests between 
such indemnified party and any other party represented by such counsel in 
such proceeding.  The failure to deliver written notice to the indemnifying 
party within a reasonable time of the commencement of any such action, if 
prejudicial to its ability to defend such action, shall relieve such 
indemnifying party of any liability to the indemnified party under this 
Section 4.6, but the omission so to deliver written notice to the 
indemnifying party 

                                  11

<PAGE>


will not relieve it of any liability that it may have to any indemnified 
party otherwise than under this Section 4.6.

                  (d)   The obligations of the Company and Holders under this 
Section 4.6 shall survive the completion of any offering of Registrable 
Securities in a registration statement under this Section 4, and otherwise.

             4.7  Reports Under Securities Exchange Act of 1934.  With a
                  ---------------------------------------------
view to making available to the Holders the benefits of Rule 144 promulgated
under the Act and any other rule or regulation of the SEC that may at any time
permit a Holder to sell securities of the Company to the public without
registration or pursuant to a registration on Form S-3, the Company agrees to:

                  (a)   make and keep public information available, as those 
terms are understood and defined in SEC Rule 144, at all times after the 
Closing;

                  (b)   file with the SEC in a timely manner all reports and 
other documents required of the Company under the Act and the Exchange Act; 
and

                  (c)   furnish to any Holder, so long as the Holder owns any 
Registrable Securities, on an annual basis or otherwise, upon request (i) a 
written statement by the Company that it has complied with the reporting 
requirements of SEC Rule 144, the Act and the Exchange Act, or that it 
qualifies as a registrant whose securities may be resold pursuant to Form S-3 
(at any time after it so qualifies), (ii) a copy of the most recent annual or 
quarterly report of the Company and such other reports and documents so filed 
by the Company and (iii) such other information as may be reasonably requested 
in availing any Holder of any rule or regulation of the SEC which permits the
selling of any such securities without registration or pursuant to any such
SEC rule or regulation.

             4.8  Assignment of Registration Rights.  The rights to cause the 
                  ---------------------------------
Company to register Registrable Securities pursuant to this Section 4 may be 
assigned by the Purchaser only to an "Affiliate" of Purchaser and, and only 
where (i) such transfer is effected in accordance with applicable federal and 
state securities laws, (ii) such Affiliate becomes a party to this Agreement 
or agrees in writing to be subject to the terms hereof to the same extent as 
if it were an original purchaser hereunder and (iii) the Company is, within a 
reasonable time after such transfer, furnished with written notice of the 
name and address of such Affiliate and the securities with respect to which 
such registration rights are being assigned; and provided, further, that such 
assignment shall be effective only if immediately following such transfer the 
further disposition of such securities by such Affiliate is restricted under 
the Act.  "Affiliate" for purposes of this Section 4.8 shall mean any 
corporation or other entity controlling, controlled by, or under common control 
with Purchaser.

             4.9  Amendment of Registration Rights.  Any provision of this 
                  --------------------------------
Section 4 may be amended and the observance thereof may be waived (either 
generally or in a particular 

                                  12

<PAGE>


instance and either retroactively or prospectively), only with the written 
consent of the Company and the Holders of a majority of the Registrable 
Securities.  Any amendment or waiver effected in accordance with this 
paragraph shall be binding upon the holder of any securities purchased under 
this Agreement at the time outstanding (including securities into which such 
securities are convertible), each future holder of all such securities, and 
the Company.

             4.10 Termination of Registration Rights.  The Company's 
                  ----------------------------------
obligations pursuant to this Section 4 shall terminate seven (7) years from 
the Effective Date.

SECTION 5.   Covenants.
             ---------

             5.1  Limitation on Sale of Stock.  Purchaser hereby agrees that 
                  ---------------------------
it will not sell any of the shares of the Stock prior to the "Permitted Sale 
Date," which shall be the earlier of (i) a Material Default by the Company or 
its Affiliates under the Dermagraft Agreements (as defined in that certain 
Heads of Agreement dated of even date between the Company and Purchaser and 
their Affiliates); or (ii) thirty (30) months after the Effective Date hereof; 
or (iii) the occurrence of one or more of the specific material changes in 
the Company as specified on Exhibit B attached hereto, and then only after 
dissemination to the public of information regarding such occurrence(s) which 
dissemination shall be made promptly following such occurrence.  After the 
Permitted Sale Date, Purchaser will be entitled to sell or transfer any or 
all of the shares of the Stock in any manner that it shall determine, 
provided that such transfer or sale is in accordance with the federal 
securities laws, and provided, further, that Purchaser shall notify in 
writing the Company of Purchaser's intention to effect sales at least two 
business days prior to the first sale effected in any thirty-day period as 
specified in Section 4 hereof; provided, however, Purchaser shall coordinate 
any such sale made in the public stock market through a nationally recognized 
underwriting firm reasonably acceptable to the Company.  These limitations on 
sale of the Stock shall be applicable on any Holder until the Stock is sold 
in the public stock market.

             5.2  Permitted Transfer.  As an exception to the transfer 
                  ------------------
restrictions set forth in Section 5.1 hereof, Purchaser may transfer the 
Stock to an Affiliate of Purchaser, so long as the Affiliate agrees in 
writing to be bound by all of the provisions of this Agreement.

SECTION 6.   Miscellaneous.
             -------------

             6.1  Survival of Warranties.  The warranties, representations 
                  ----------------------
and covenants of the Company contained in or made pursuant to this Agreement 
shall survive the execution and delivery of this Agreement and the Closing 
and shall in no way be affected by any investigation of the subject matter 
thereof made by or on behalf of the Purchaser.

             6.2  Successors and Assigns.  The terms and conditions of this 
                  ----------------------
Agreement shall inure to the benefit of and be binding upon the respective 
permitted successors and assigns of the parties.  Nothing in this Agreement, 
express or implied, is intended to confer upon any party 

                                  13

<PAGE>


other than the parties hereto or their respective permitted successors and 
assigns any rights, remedies, obligations, or liabilities under or by
reason of this Agreement, except as expressly provided in this Agreement.

             6.3  Governing Law.  This Agreement shall be governed by and 
                  -------------
construed under the laws of the State of Delaware.

             6.4  Counterparts.  This Agreement may be executed in two or 
                  ------------
more counterparts, each of which shall be deemed an original, but all of 
which together shall constitute one and the same instrument.

             6.5  Titles and Subtitles.  The titles and subtitles used in 
                  --------------------
this Agreement are used for convenience only and are not to be considered in 
construing or interpreting this Agreement.

             6.6  Assignment.  This Agreement may not be assigned or otherwise 
                  ----------
transferred, nor, except as expressly provided hereunder, may any right or 
obligations hereunder be assigned or transferred, by either party without the 
written consent of the other party; provided, however, that either the 
Company or the Purchaser may, without such consent, assign this Agreement and 
its rights and obligations thereunder (a) in connection with the transfer or 
sale of all or substantially all of its business, if such assets include 
substantially all of the assets relating to its performance of its respective 
obligations hereunder, (b) to a wholly owned subsidiary or (c) in the event 
of its merger or consolidation with another company at any time during the 
term of this Agreement.  Any purported assignment in violation of the 
preceding sentence shall be void.  Any permitted assignee shall assume all 
obligations of its assignor under this Agreement.

             6.7  Notices.  Any notice or report required or permitted to be 
                  -------
given or made under this Agreement by one of the parties hereto to the other 
shall be in writing, delivered personally or by facsimile (and promptly 
confirmed by personal delivery or courier) or courier, postage prepaid, 
addressed to such other party at its address indicated below, or to such 
other address as the addressee shall have last furnished in writing to the 
addressor and shall be effective upon receipt by the addressee.

     The Company:

             Advanced Tissue Sciences, Inc.
             10933 North Torrey Pines Road
             La Jolla, California 92037
             Attention: Office of the General Counsel
             (619) 450-5730
             (619) 450-5732 fax

                                  14

<PAGE>


     The Purchaser:
     
             Smith & Nephew SNATS, Inc.
             One Commerce Center, Ste. 788
             1201 N. Orange Street
             Wilmington, Delaware 19801-1119
             Attn:  President
             Fax:  302/884-6752

     with a copy to:

             Smith & Nephew plc
             2 Temple Place
             Victoria Embankment
             London WC2R3BP
             England
             Attn:  Company Secretary
             Fax:  011-44-171-240-7088

     and a copy to:

             Smith & Nephew Inc.
             1450 E. Brooks Road
             Memphis, Tennessee 38116
             Attn:  General Counsel
             Fax:  901/396-7824

             6.8  Finder's Fee.  Each party represents that it neither is 
                  ------------
nor will be obligated for any finders' fee or commission in connection with 
this transaction.  Each party agrees to indemnify and hold harmless the other 
party from any liability for any commission or compensation in the nature of 
a finders' fee (and the costs and expenses of defending against such liability 
or asserted liability) for which the party or any of its officers, partners, 
employees or representatives is responsible.

             6.9  Expenses.  Irrespective of whether the Closing is effected, 
                  --------
each party shall bear its own costs with respect to the negotiation, 
execution, delivery and performance of this Agreement.  If any action at law 
or in equity is necessary to enforce or interpret the terms of this Agreement 
or the Company's Certificate of Incorporation, the prevailing party shall be 
entitled to reasonable attorney's fees, costs and necessary disbursements in 
addition to any other relief to which such party may be entitled.

             6.10 Amendments and Waivers.  Except as specified in Section 4.9, 
                  ----------------------
any term of this Agreement may be amended and the observance of any term of 
this Agreement may be waived (either generally or in a particular instance 
and either retroactively or prospectively), only with the written consent of 
the Company and Purchaser.  Any amendment or waiver effected in 

                                  15

<PAGE>


accordance with this paragraph shall be binding upon each Holder of any 
securities purchased under this Agreement at the time outstanding (including 
securities into which such securities are convertible), each future holder of 
all such securities, and the Company; provided, however, that no condition 
set forth in Section 5 hereof may be waived, unless the Company consents 
thereto.

             6.11 Severability.  If one or more provisions of this Agreement 
                  ------------
are held to be unenforceable under applicable law, such provision shall be 
excluded from this Agreement and the balance of this Agreement shall be 
interpreted as if such provision were so excluded and shall be enforceable in 
accordance with its terms.

             6.12 Aggregation of Stock.  All shares of Stock held or acquired 
                  --------------------
by affiliated entities or persons shall be aggregated together for the 
purpose of determining the availability of any rights under this Agreement.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

                                      ADVANCED TISSUE SCIENCES, INC.

                                      By:  _________________________________

                                      Title:  ______________________________



                                      SMITH & NEPHEW SNATS, INC.

                                      By:  _________________________________

                                      Title:  ______________________________


                                  16


<PAGE>




                                   EXHIBIT A

                            SCHEDULE OF EXCEPTIONS



<PAGE>


                                   EXHIBIT B

                        DEFINITION OF MATERIAL CHANGES

                                 (Section 5.1)

     1.    ATS publicly announces a proposed merger of ATS with another 
           company, pursuant to which the former shareholders of ATS will 
           own less than 75% of the combined voting equity of the merged 
           entity.
 
     2.    ATS sells its voting equity stock to a party such that the party 
           (and its Affiliates) owns more than 25% of all of the ATS voting 
           equity stock.
 
     3.    ATS sells a component or components of the ATS business over a 
           rolling 12-month period for consideration in excess of 33% of the 
           total ATS market capitalization at the time of the public 
           announcement of the sale.  (A licensing transaction for a 
           strategic alliance in which ATS will continue to be involved is 
           not a sale for purposes of this section.)

     4.    The termination of either Arthur J. Benvenuto or Gail K. Naughton 
           as executives of ATS, without a mutually acceptable replacement 
           executive being hired by ATS, with S&N's acceptance (or 
           disapproval) to be given based upon S&N's good faith and 
           reasonable discretion.
 
     5.    The share price for ATS common stock falls below $6.00 for two
           consecutive days, as shown on last reported sale for the day on 
           the Nasdaq National Market.

     6.    The ATS Board of Directors decides, and makes a public 
           announcement of said decision, to make a fundamental change in 
           the business of ATS such that ATS focus is no longer principally 
           in the area of human tissue engineered products.





© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission