IMCLONE SYSTEMS INC/DE
SC 13D, 1999-10-18
BIOLOGICAL PRODUCTS, (NO DIAGNOSTIC SUBSTANCES)
Previous: NWQ INVESTMENT MANAGEMENT CO /CA/, 13F-HR, 1999-10-18
Next: FIRST INVESTORS LIFE SERIES FUND, 485BPOS, 1999-10-18




                                                   UNITED STATES
                                        SECURITIES AND EXCHANGE COMMISSION
                                              Washington, D.C.  20549

                                                   SCHEDULE 13D

                                     Under the Securities Exchange Act of 1934
                                                 (Amendment No.)*

                                           ImClone Systems Incorporated
                                                 (Name of Issuer)

                                                   Common Stock
                                          (Title of Class of Securities)

                                                     45245W109
                                                  (CUSIP Number)

                                                Marc Weitzen, Esq.
                                        Gordon Altman Weitzen Shalov & Wein
                                         114 West 47th Street, 20th Floor
                                             New York, New York 10036
                                                  (212) 626-0800

                    (Name, Address and Telephone Number of Person Authorized to
                                       Receive Notices and Communications)

                                                  October 7, 1999
                        (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the  acquisition which is the subject of this  Schedule 13D, and is filing this
schedule because of ss.ss.240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the
following box / /.

NOTE:  Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for
other parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities,
and for  any  subsequent   amendment   containing   information  which  would
alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the  Securities  Exchange
Act of 1934 ("Act") or otherwise  subject to the liabilities of that section of
the Act but  shall be  subject  to all other  provisions  of the Act  (however,
see the Notes).



<PAGE>



                                                   SCHEDULE 13D

CUSIP No. 45245W109


1        NAME OF REPORTING PERSON
                  High River Limited Partnership

         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON 13-3626974


2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                        (a) /X/
                                                                         (b) //

3        SEC USE ONLY

4        SOURCE OF FUNDS*
                  WC

5        CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
         ITEMS 2(d) or 2(e)                                                  //

6        CITIZENSHIP OR PLACE OF ORGANIZATION
                  Delaware


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

         7        SOLE VOTING POWER
                           1,294,100 **

         8        SHARED VOTING POWER
                           0

         9        SOLE DISPOSITIVE POWER
                           1,294,100 **

         10       SHARED DISPOSITIVE POWER
                           0

11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                  1,294,100 **

12       CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
SHARES*
                  //

13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
                  5.1%

14       TYPE OF REPORTING PERSON*
                  PN



** See Item 5.


<PAGE>



                                                          SCHEDULE 13D

CUSIP No. 45245W109


1        NAME OF REPORTING PERSON
                  Riverdale LLC

         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON 13-3903766


2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                        (a) /X/
                                                                         (b) //

3        SEC USE ONLY

4        SOURCE OF FUNDS*
                  WC

5        CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
         ITEMS 2(d) or 2(e)                                                  //

6        CITIZENSHIP OR PLACE OF ORGANIZATION
                  New York


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

         7        SOLE VOTING POWER
                           0

         8        SHARED VOTING POWER
                           1,294,100 **

         9        SOLE DISPOSITIVE POWER
                           0

         10       SHARED DISPOSITIVE POWER
                           1,294,100 **

11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                  1,294,100 **

12       CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
SHARES*
                  //

13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
                  5.1%

14       TYPE OF REPORTING PERSON*
                  OO



** See Item 5.


<PAGE>



                                                          SCHEDULE 13D

CUSIP No. 45245W109


1        NAME OF REPORTING PERSON
                  Carl C. Icahn

         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON


2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                        (a) /X/
                                                                         (b) //

3        SEC USE ONLY

4        SOURCE OF FUNDS*
                    WC

5        CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
         ITEMS 2(d) or 2(e)                                                 //

6        CITIZENSHIP OR PLACE OF ORGANIZATION
                  United States of America


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

         7        SOLE VOTING POWER
                           0

         8        SHARED VOTING POWER
                           1,294,100 **

         9        SOLE DISPOSITIVE POWER
                           0

         10       SHARED DISPOSITIVE POWER
                           1,294,100 **

11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                           1,294,100 **

12       CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
SHARES*
                  //

13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
                           5.1%

14       TYPE OF REPORTING PERSON*
                  IN



** See Item 5.


<PAGE>



                                                   SCHEDULE 13D
                                                   ------------


Item 1.  Security and Issuer

                 This  Schedule  13D  relates  to the common  stock,  par value
$0.001  per share  ("Shares"), of  ImClone  Systems  Incorporated,  a  Delaware
corporation (the "Issuer"). The address of the principal  executive  offices of
the Issuer is 180 Varick Street, New York, New York 10014.


Item 2.  Identity and Background

                  The  persons filing  this  statement  are High River  Limited
Partnership, a Delaware limited partnership ("High River"), Riverdale LLC, a
New York limited liability company ("Riverdale") and Carl C. Icahn, a citizen
of the United  States of  America  (collectively,  the  "Registrants").  The
principal business  address and the address of the principal  office of the
Registrants is 100 South Bedford Road, Mount Kisco, New York 10549,  with the
exception of Carl C. Icahn,  whose principal  business address is c/o Icahn
Associates  Corp., 767 Fifth Avenue, 47th Floor, New York, New York 10153.

                 Riverdale is the general  partner of High River.  Riverdale is
wholly owned by Carl C. Icahn. Registrants may be deemed to be a "group" within
the meaning of Section 13(d)(3) promulgated under the Securities Exchange Act
of 1934, as amended (the "Act").

                 High River is  primarily  engaged in the business of investing
in  securities. Riverdale is  primarily  engaged in the business of owning real
estate and acting as general  partner of High  River.  Carl C. Icahn's  present
principal  occupation  or  employment  is acting as President and a Director of
Starfire Holding Corporation,  a Delaware corporation  ("Starfire"), and as the
Chairman  of the  Board  and  Director  of  various  subsidiaries  of Starfire,
including  ACF  Industries,  Incorporated,  a New  Jersey  corporation ("ACF").
Starfire,  whose  principal  business  address is 100 South Bedford Road, Mount
Kisco, New York 10549, is primarily  engaged in the business of holding, either
directly or through its subsidiaries, a majority of the common stock of ACF.
ACF is  primarily  engaged in the  business  of leasing,  selling and
manufacturing railroad freight and tank cars.




<PAGE>




                 The  name,   citizenship,   present  principal  occupation  or
employment  and business  address of each member of  Riverdale  is set forth in
Schedule A attached hereto.

                  Carl C. Icahn is a member of Riverdale and owns 100% of
the interests therein.  As such, Mr. Icahn is in a position
directly and indirectly to determine the investment and voting
decisions made by Registrants.

                 Neither High River,  Riverdale,  Mr. Icahn,  nor any executive
officer or director of any of the Registrants, has, during the past five years,
(a) been convicted in a criminal  proceeding (excluding  traffic  violations or
similar  misdemeanors), or (b) been a party to a civil proceeding of a judicial
or  administrative  body  of competent  jurisdiction  and as a  result  of such
proceeding  was or is subject to a  judgment, decree or final  order  enjoining
future  violations of, or prohibiting,  or  mandating  activities  subject to,
Federal or State securities  laws or a finding of any violation with respect to
such laws.


Item 3.  Source and Amount of Funds or Other Consideration

                 The aggregate  purchase price of 844,100  Shares  purchased by
the  Registrants is $18,162,133.45.  The  Registrants  beneficially  own a call
option with the right to purchase 300,000  Shares at an exercise  price of $.50
per share and a call  option  with the right to purchase  150,000  Shares at an
exercise  price of $2.00 per share.  Both of these options  expire on April 27,
2000. The source of funding for the purchase of these Shares is general working
capital of the Registrants.


Item 4.           Purpose of Transaction

                  The  Registrants  have acquired  the Shares of the Issuer for
investment  purposes.  Depending on market conditions  and other  factors,  the
Registrants  may  acquire   additional   Shares  of  the Issuer  as  they  deem
appropriate, whether in open market purchases, privately negotiated
transactions or otherwise.  The Registrants  also reserve the right to dispose
of some or all of their Shares in the open  market,  in privately  negotiated
transactions  to third parties or otherwise.


Item 5.           Interest in Securities of the Issuer

                 (a)  As  of  the  close  of   business  on  October  7,  1999,
Registrants may be deemed to beneficially own in the aggregate  1,294,100
Shares representing  approximately 5.1% of the Issuer's  outstanding Shares
(based upon the  25,564,233  Shares stated to be outstanding as of
September 1, 1999, by the Issuer in the  Issuer's  S-3  filing  filed  with
the  Securities  and  Exchange Commission  (the  "SEC") on October 6,  1999).
The  aggregate  number of shares beneficially owned by the Registrants includes
the


<PAGE>



options of High River to purchase  450,000  Shares, as more fully  described in
Item 6 herein and attached as Exhibit 2 and Exhibit 3 hereto. Registrants  have
direct beneficial ownership of the Shares as follows:

<TABLE>

<CAPTION>

         NAME                       NUMBER OF                          APPROXIMATE PERCENTAGE
                                    SHARES                             OF OUTSTANDING SHARES

<S>                                 <C>                                <C>
         High River                 1,294,100                          5.1%

</TABLE>

                  Riverdale and Mr. Icahn, by virtue of their relationships  to
High River (as disclosed in Item 2), may be deemed to beneficially own (as that
term is  defined  in Rule  13d-3  under the Act) the  Shares  which High  River
directly beneficially owns. Each of Riverdale and Mr. Icahn disclaims
beneficial ownership of such Shares for all other purposes.

                 To the best of  Registrants'  knowledge,  except  as set forth
herein, neither the  directors nor the  executive  officers of the  Registrants
beneficially own any Shares.

                 (b) High  River has sole  voting  power  and sole  dispositive
power with regard to 1,294,100  Shares.  Riverdale  has shared voting power and
shared  dispositive  power with regard to  1,294,100  Shares. Carl C. Icahn has
shared  voting  power and  shared  dispositive  power with  regard to 1,294,100
Shares.

                  (c) The  following  table  sets  forth all  transactions with
respect to Shares  effected  during  the past sixty days by each of the persons
named in Item 5(a) above.  All  transactions listed in the following table were
executed on NASDAQ.

<TABLE>

<CAPTION>

         DATE                               NUMBER OF SHARES                            PRICE PER SHARE
                                    PURCHASED

<S>                                                  <C>                                                  <C>
         September 29, 1999                            4,800                                              32.0547
         September 30, 1999                           22,300                                              30.7904
         October 5, 1999                              50,000                                              29.9288
         October 6, 1999                             130,000                                              25.8426
         October 7, 1999                             387,000                                              22.0876


</TABLE>




<PAGE>



                 (d) No other  person  has the right to receive or the power to
direct the  receipt of  dividends  from, or the  proceeds  from the sale of any
Shares which Registrants may be deemed to beneficially own.

                  (e)      Not applicable.

Item 6.           Contracts, Arrangements, Understandings or Relationship
                  with Respect to Securities of the Issuer

                 Registrants are party to a Joint Filing  Agreement,  a copy of
which is attached  hereto as  Exhibit  1, with  respect  to the  filing of this
statement and any amendments thereto.

                 High River is party to an Option Agreement, a copy of which is
attached  hereto as  Exhibit 2, dated as of April 27,  1995,  with the  Issuer,
pursuant  to which the Issuer has  granted to High River an option to  purchase
150,000 Shares for a price per share equal to $2.00.

                 High River is party to an Option Agreement, a copy of which is
attached  hereto as Exhibit  3, dated as of April 27,  1995,  with the  Issuer,
pursuant  to which the Issuer has  granted to High River an option to  purchase
300,000 Shares for a price per share equal to $0.50.

Item 7.           Material to be Filed as Exhibits

1. Joint Filing Agreement of the Registrants
2. Option  Agreement,  dated as of April 27, 1995, between ImClone Systems
Incorporated,  a Delaware  corporation, and High River Limited Partnership,
a Delaware limited  partnership.
3. Option Agreement,  dated as of April 27, 1995, between ImClone Systems
Incorporated,  a Delaware  corporation,  and High River Limited  Partnership,
a Delaware limited partnership.



<PAGE>



                                                     SIGNATURE
                                                     ---------


                 After  reasonable  inquiry and to the best of my knowledge and
belief,  I certify that the  information  set forth in this  statement is true,
complete and correct.

Dated: October 18, 1999




RIVERDALE LLC

By:      /s/Carl C. Icahn
         Carl C. Icahn
Its:     Member


HIGH RIVER LIMITED PARTNERSHIP

By:      RIVERDALE LLC

Its:     General Partner

By:      /s/Carl C. Icahn
         Carl C. Icahn
Its:     Member


Carl C. Icahn

By:      /s/Carl C. Icahn
         Carl C. Icahn


















                  (Signature Page of Schedule 13D with respect to ImClone
Systems Incorporated)


<PAGE>



                                                    SCHEDULE A
                                                    ----------

                            DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANTS


         Name, Business Address and Principal Occupation of
         Each Member of Riverdale

         The following sets forth the name, position,  and principal occupation
of each member of Riverdale. Each such person is a citizen of the United States
of America. Except as otherwise indicated, the business address of each
director and officer is c/o Icahn  Associates  Corp.,  767 Fifth Avenue,
47th Floor, New York, New York 10153. To the best of Registrants' knowledge,
except as set forth in this  statement on Schedule 13D, none of the directors
or executive  officers of the Registrants own any shares of the Issuer.

RIVERDALE LLC

<TABLE>
<CAPTION>

Name                                Position                                    Principal Occupation
- ----                                --------                                    --------------------
<S>                                 <C>                                         <C>
Carl C. Icahn                       Member                                      See Item 2 herein
                                                                                Officer of various Icahn
                                                                                affiliated entities
</TABLE>
























                                                     EXHIBIT 1


                                              JOINT FILING AGREEMENT

                 In accordance with Rule 13d-1(k) under the Securities Exchange
Act of 1934,  as  amended, each of the  persons  named below agree to the joint
filing of a statement  on Schedule  13D,  including  amendments  thereto,  with
respect to the common  stock, par value  $0.001 per share,  of ImClone  Systems
Incorporated,  and further agree that this Joint Filing Agreement be included as
an  exhibit  to  such  filings,  provided  that,  as  contemplated  by  Section
13d-1(k)(1)(ii), no person shall be responsible for the completeness or
accuracy of the information  concerning the other persons making the filing,
unless such person knows or has reason to believe that such information is
inaccurate.

                 This Joint Filing  Agreement  may be executed in any number of
counterparts, all of  which  collectively  shall  constitute  one and the  same
instrument.


Dated:  October 18, 1999


/RIVERDALE LLC

By:      /s/Carl C. Icahn
         Carl C. Icahn
Its:     Member


HIGH RIVER LIMITED PARTNERSHIP

By:      RIVERDALE LLC

Its:     General Partner

By:      /s/Carl C. Icahn
         Carl C. Icahn
Its:     Member


Carl C. Icahn

By:      /s/Carl C. Icahn
         Carl C. Icahn


<PAGE>




                                                     EXHIBIT 2

                                                 OPTION AGREEMENT


        OPTION AGREEMENT dated as of April 27, 1995 (the "Agreement"),  between
ImClone Systems Incorporated, a Delaware Corporation ("ImClone"), and High
River Limited Partnership, a Delaware limited partnership ("High River").

        WHEREAS,  pursuant to an option  agreement of even date, High River has
agreed to grant to ImClone a certain  option (the "Cadus  Option")  pursuant to
which High River will sell to ImClone,  upon the terms and conditions contained
therein,  1,050,000  shares of Common  Stock,  $.001  par value per  share, and
2,188,184  shares of Series A  Preferred  Stock,  $.001 par value per share, of
Cadus Pharmaceutical Corporation, a Delaware corporation;

         WHEREAS,  as  consideration for the  grant by High  River of the Cadus
Option, ImClone has agreed to grant to High River the option described herein;

         NOW THEREFORE, in consideration of the mutual covenants and agreements
set forth herein, the parties hereto agree as follows:

                  1. Grant of  Option.  ImClone hereby  grants to High River an
option (the "Option") to purchase, on the terms and conditions set forth
herein, 150,000 shares of common stock of ImClone,  par value $.001 per share
("ImClone Common  Stock")  for a price per share  equal to $2.00
(the  "Exercise  Price"), subject to adjustment  pursuant to Section 4 hereof
(the "Option  Shares").  The Option  granted  hereby shall  terminate and
expire at 5:00 p.m.,  New York City time, on April 27, 2000
(the "Expiration Date").

                 2. Exercise of Option.  High River may exercise this Option in
whole or in part at any time from time to time commencing on the date hereof
and continuing through the Expiration Date.

                  3.       Exercise of Option.

                          a.      To exercise the Option, High River shall give
written  notice to ImClone of such exercise,  which  notice  shall  specify the
number of Option Shares to be purchased and the place, date and time designated
by High  River for the  closing of such  purchase,  which date shall not be
less than 5  business  days nor more  than 15  business  days  after the date
of such notice.  Notwithstanding  any provision of this  Agreement to the
contrary,  the giving of any  exercise  notice by High River shall not
obligate  High River to consummate any purchase hereunder.

                           b.     At each closing:  (i) High River will (x) pay
to  ImClone,  by  delivery of a certified  or bank  cashier's check  payable in
immediately  available  funds,  an amount  equal to the product of the Exercise
Price and the  number of Option  Shares  specified  in the  applicable exercise
notice and (y) provide to



<PAGE>



ImClone  a letter  signed by High  River to the effect  that (A) High  River is
acquiring such Option Shares for its own account, and not with a view to, or
for resale in connection with, the distribution  thereof, and that High River
has no present  intention of  distributing  or reselling such shares and (B)
High River agrees that such Option  Shares shall not be sold or  transferred
unless either (1) they first shall have been  registered  under the Securities
Act of 1933, as amended (the "Act"),  and  applicable  state  securities or
blue sky laws or (2) ImClone  first  shall  have been  furnished  with an
opinion  of legal  counsel acceptable  in form and  substance  to ImClone (in
its sole  discretion)  to the effect  that such sale or transfer  is exempt
from the  foregoing  registration requirement   and  (ii)   ImClone  will
deliver  to  High  River  one  or  more certificates,  registered  in High
River's  name or in the name of any  nominee designated by High River,
representing such Option Shares.

                  4.       Adjustments

                          a.       In case after the date hereof, ImClone shall
(i)  pay a dividend  or make a  distribution  on  ImClone  Common  Stock,  (ii)
subdivide the outstanding shares of ImClone Common Stock into a larger number
of shares of ImClone Common Stock,  (iii) combine the outstanding shares of
ImClone Common  Stock into a smaller  number of shares of ImClone  Common
Stock or (iv) increase or decrease the number of shares of ImClone Common
Stock outstanding by reclassification  of the ImClone Common Stock,  then the
number of Option Shares purchasable upon exercise of the Option  immediately
after the happening of such event shall be  adjusted  so that High River
shall be entitled to receive  upon exercise of this  Option,  the number of
shares of ImClone  Common Stock and, in the case of a dividend or
distribution  other than in shares of ImClone  Common Stock, the cash,
securities or other property so dividended or distributed, that High  River
would  have  owned or have been  entitled  to  receive  immediately following
the  happening of such event,  had the Option been  exercised in full
immediately  prior  thereto  (or, in the case of a dividend or  distribution on
ImClone Common Stock,  immediately  prior to the record date therefor), and the
Exercise  Price  for  the  Option  shall  be  adjusted  in  inverse  proportion
(calculated  to the nearest .001 of a cent). If the amount of any adjustment of
the Exercise Price required pursuant to this Section 4(a) would be less than
two percent  (2%) of the  Exercise  Price in effect at the time such
adjustment  is otherwise  so required  to be made,  such  amount  shall be
carried  forward and adjustment  with  respect  thereto  made at the  time of
and  together  with any subsequent  adjustment which,  together with such
amount and any other amount or amounts so carried  forward,  shall  aggregate
at least two percent (2%) of such Exercise  Price.  An adjustment  made
pursuant to this Section 4(a) shall become effective  immediately after the
effective date,  retroactive to the record date therefore in the case of a
dividend or  distribution on shares of ImClone Common Stock,  and shall
become effective  immediately  after the effective date in the case of a
subdivision, combination or reclassification of ImClone Common Stock.



<PAGE>



                           b.       In case ImClone after the date hereof (i)
shall  consolidate  with or merge  into any other  person  and shall not be the
continuing or surviving  corporation of such consolidation  or merger,  or (ii)
shall  permit any other  person to  consolidate with or merge into  ImClone and
ImClone shall be the continuing or surviving person but,in connection with such
consolidation or merger,ImClone Common Stock shall be changed into or exchanged
for stock or other securities of any other person or cash or any other
property, or (iii) shall transfer all or substantially  all of its properties
or assets to any  other   person  or  (iv)   shall   effect  a  capital
reorganization   or reclassification of ImClone Common Stock, then proper
provision shall be made so that  High  River,  upon  any  exercise  of the
Option  at any time  after  the consummation of such transaction, shall be
entitled to receive (at the aggregate Exercise Price in effect at the time of
such  consummation for all Option Shares issuable upon such exercise
immediately prior to such consummation),  in lieu of the ImClone Common Stock
issuable upon such exercise prior to such consummation, the amount of
securities,  cash or other  property  to which  High River  would actually
have been  entitled as a shareholder  upon such  consummation  if High River
had exercised the Option immediately prior thereto. After the consummation of
any such  transaction,  "Option Shares" shall refer to such other securities,
cash or other property.

                           c.       Notwithstanding any provision in this
Agreement  to the contrary,  ImClone  will not effect  any of the  transactions
described in clauses(i) through (iv) of Section  4(b) hereof  unless,  prior to
the consummation thereof,each person (other than ImClone) which may be required
to deliver  any stock, securities,  cash or property  upon the  exercise of the
Option as provided herein shall assume,by written  instrument  delivered to and
reasonably  satisfactory  to High River, the  obligations of ImClone under this
Agreement.

                  5.  Representations and Warranties of ImClone. ImClone hereby
represents and warrants to High River as follows:

                           a.       Due Authorization, etc.  ImClone has all
necessary  corporate  power and authority to execute and deliver this
Agreement. The  execution  and  delivery  of this  Agreement  and the
consummation  of the transactions  contemplated  hereby have been duly
authorized  by all  necessary corporate  action on the part of ImClone.  This
Agreement has been duly executed and  delivered by a duly  authorized  officer
of ImClone,  constitutes  a legal, valid and binding  agreement of ImClone and
is  enforceable  against  ImClone in accordance with its terms,  except as
such  enforceability may be limited by (i) the effect of bankruptcy,
insolvency, reorganization, moratorium, marshalling or other  similar  laws
now or hereafter  in effect  relating to or  affecting  the rights and
remedies of  creditors  generally  and (ii)  general  principles  of
equity,  whether such  enforceability is considered in a proceeding in equity
or at law.



<PAGE>



                          b.       Option Shares.  All of the Option Shares to
be acquired upon exercise of the Option shall be duly and validly issued, fully
paid  and  non-assessable  and  shall be free and  clear of any  liens, claims,
charges,  rights of others,  security interests, options or encumbrances of any
nature,  including preemptive rights. ImClone has taken all necessary corporate
and other  action to  authorize, to reserve and to permit it to sell and issue,
and at all times from the date hereof until such time as ImClone's obligation
to sell and deliver shares of ImClone Common Stock hereunder terminates,  will
have reserved for issuance upon exercise of the Option,  the maximum number of
Option Shares that High River has the right to purchase hereunder.

                           c.       No Conflicts; No Consents.  Neither the
execution and  delivery by ImClone of this  Agreement  nor the  performance  by
ImClone of its  obligations hereunder  will:  (i) violate or conflict  with any
provision of ImClone's Certificate of Incorporation or By-Laws, in each case as
in effect on the date hereof and on the date of any closing hereunder;(ii) with
or without the giving of notice or the passage of time, or both, violate, or be
in conflict with, or permit the  termination of, or constitute a default under,
or cause the acceleration of the maturity of,any agreement,  debt or obligation
of any  nature of  ImClone  or to which  ImClone is a party or it or any of its
properties is bound;  (iii) require the consent of any party to any  agreement,
instrument  or  commitment to which ImClone is a party or to which it or any of
its  properties  is bound; (iv)  violate  any  statute or law or any  judgment,
decree,  order,  regulation or  rule  of any  court,  regulatory  authority  or
governmental agency or authority to which  ImClone or any of its  properties is
subject; or (v) result in the creation of any lien or other  encumbrance on its
assets. No consent,  approval or  authorization  of, or declaration,  filing or
registration with,any regulatory  authority or governmental agency or authority
is required to be made or obtained by ImClone in connection  with the
execution, delivery and  performance of this  Agreement,  the performance by
ImClone of its obligations  hereunder  or the con  summation of the
transactions  contemplated hereby.  ImClone  is  not a  party  to  any
material  contract,  commitment  or agreement, nor is ImClone subject to, or
bound by, any order, judgment,  decree, law, statute,  ordinance,  rule,
regulation or other restriction of any kind or character, which would prevent
ImClone from entering into this Agreement or from consummating the trans
actions contemplated hereby.

                 6.  Representation  and  Warranty  of High  River.  High River
hereby represents and warrants to ImClone as follows:

                 a. Due Authorization, etc. High River has full
power and  authority to execute and deliver this  Agreement. The  execution and
delivery of this Agreement and the consummation of the transactions
contemplated hereby have been duly authorized by all necessary partnership
action on the part of High River. This Agreement has been duly executed and
delivered by a duly



<PAGE>



authorized  signatory  of High  River,  constitutes a legal,  valid and binding
agreement of High River and is enforceable against High River in accordance
with its  terms,  except as such  enforceability  may be limited by (i) the
effect of bankruptcy, insolvency, reorganization, moratorium, marshalling or
other similar laws now or hereafter in effect relating to or affecting the
rights and remedies of creditors  generally  and (ii)  general  principles  of
equity,  whether such enforceability is considered in a proceeding in equity
or at law.

                           b. Investment.  High River is acquiring this
Option for its own account for investment and not with a view to,or for sale in
connection with, any  distribution  thereof,  nor with any present intention of
distributing  or selling the same;and High River has no present or contemplated
agreement,  undertaking,  arrangement,  obligation, indebtedness  or commitment
providing for the disposition thereof. High River is aware that this Option and
the Option  Shares are not being  registered under the Act or under  applicable
state securities or blue sky laws, and that the certificate(s) representing the
Option Shares will bear the following legend:

                 "THE  SECURITIES  REPRESENTED  BY THIS  INSTRUMENT  HAVE  BEEN
                 ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE
                 SECURITIES  ACT  OF  1933  (THE  "ACT")  OR  APPLICABLE  STATE
                 SECURITIES OR BLUE SKY LAWS.  THE  SECURITIES  REPRESENTED  BY
                 THIS INSTRUMENT MAY NOT BE OFFERED FOR SALE,  SOLD,  DELIVERED
                 AFTER  SALE,  TRANSFERRED,  PLEDGED  OR  HYPOTHECATED  IN  THE
                 ABSENCE OF (1) AN EFFECTIVE  REGISTRATION  STATEMENT  COVERING
                 SUCH SECURITIES  UNDER THE ACT AND APPLICABLE STATE SECURITIES
                 OR BLUE SKY LAWS OR (2) AN  OPINION  OF  COUNSEL TO THE EFFECT
                 THAT  SUCH  REGISTRATION  IS NOT  REQUIRED  UNDER  THE ACT AND
                 APPLICABLE  STATE  SECURITIES OR BLUE SKY LAWS,  WHICH OPINION
                 SHALL BE  ACCEPTABLE  IN FORM AND  SUBSTANCE TO THE COMPANY IN
                  ITS SOLE DISCRETION."

                 7. ImClone Covenants.  ImClone covenants and agrees that, from
the date hereof through the Expiration Date, it will take all action  necessary
so that each of ImClone's  representations and warranties  contained  herein is
true,  complete  and correct at all times until the  termination  of  ImClone's
obligation to sell and deliver shares of ImClone Common Stock hereunder.

                  8.       Registration Under Securities Act.

                  a. (i) Upon written request by High River, ImClone will cause
to be prepared and filed a registration statement under the Act relating to
such number of Option  Shares as may be designated by High River and ImClone
will use its best efforts to



<PAGE>



cause such registration statement to become effective;  provided, however, that
High River shall be required to  register  no less than  150,000 Option  Shares
under any such registration statement.High River shall have the right to select
the  underwriter  or  underwriters who shall make the offering,  if it is to be
underwritten,  but High  River's selection  must be approved by ImClone,  which
approval  shall  not  be   unreasonably  withheld.   ImClone  shall  keep  such
registration  statement effective  until it is  permitted  to withdraw the same
pursuant to Section  8(c). Notwithstanding  anything to the  contrary set forth
herein,  ImClone  may delay the  filing or  effectiveness  of any  registration
statement  for a  period of up to 120 days  after  the  date of a  request  for
registration  pursuant to this Section  8(a)(i) if at the time of such  request
ImClone is engaged in a firm commitment underwritten public offering.

                           (ii) If at any time when High River owns any
shares of ImClone Common Stock acquired pursuant to the exercise of this
Option, ImClone  effects a  registration  of ImClone Common Stock for its own
account or for the  account of any other  shareholder  of ImClone  in
connection  with the public offering of such ImClone Common Stock (other
than on Form S-4 or Form S-8 or any  successor  form),  it shall  allow
High  River to  participate  in such registration;  provided,  however, if
the managing underwriters in such offering advise  ImClone in writing that in
their opinion the number of shares of ImClone Common Stock  requested to be
included in such  registration  exceeds the number which can be sold in such
offering at the proposed offering price, the number of shares of  ImClone
Common  Stock  owned by High  River to be  included  in such registration
shall be reduced to such number that will make the aggregate shares of
ImClone  Common Stock so registered  not in excess of the number of shares of
ImClone Common Stock that the  underwriters  believe can be sold at the
proposed price.  In connection  with any offering  involving an  underwriting
of ImClone Common Stock for ImClone's account or for the account of any other
shareholder, ImClone  shall not be required  under this  subparagraph  (ii)
to include any of High River's ImClone Common Stock in such underwriting
unless High River accepts the reasonable terms of the underwriting as agreed
upon by ImClone or such other shareholder,  accepts  such  underwriters
selected  by  ImClone  or such  other shareholder  and  agrees to enter
into and  perform  its  obligations  under an underwriting  agreement,  in
usual and customary form,  with such  underwriters. ImClone  shall be under
no obligation  to complete any  registration  of ImClone
Common Stock it proposes to make and shall incur no liability to High River for
its failure to do so (and its failure to complete the registration of shares of
ImClone Common Stock included in such  registration by High River in connection
therewith).

                (iii) If, during the period when any registration
statement  covering  shares  of  ImClone  Common Stock  owned by High  River is
effective,any event occurs as a result of which the prospectus included in such
registration  statement, as then in effect,would include an untrue statement of
a material fact or



<PAGE>



omit to state a material  fact  required to be stated  therein, or necessary in
order to make the statements  made not misleading in light of the circumstances
then existing,  or it shall be necessary to amend or supplement such prospectus
to comply with applicable law, ImClone will forthwith notify High River thereof
and, at High  River's  request, ImClone will (a) prepare and file under the Act
such  amendments  and  supplements as may be  necessary  to  keep  available  a
prospectus  covering such registered stock meeting the requirements of the Act,
and (b) furnish to the  underwriters, if any,  and to High River such number of
copies of each of the  registration statement  and  prospectus  as  amended  or
supplemented  as may  reasonably  be requested  from  time to  time;  provided,
however,  that once High River is notified by ImClone of the  happening  of any
event of the kind described above in this subparagraph  (iii),  High River will
thereafter  immediately  discontinue  the  distribution  of  such  registration
statement or prospectus and the disposition of ImClone Common Stock pursuant to
such  registration  statement or  prospectus  until such time as High River has
received  from  ImClone  a  copy or  copies  of  the  amended  or  supplemental
registration  statement or prospectus contemplated by this subparagraph  (iii),
and if so directed by ImClone in its notice,High River shall deliver to ImClone
all copies, other than permanent file copies,then in High River's possession of
the  registration  statement or prospectus covering such ImClone  Common Stock;
provided  further,  that ImClone  shall deliver to High River within 15 days of
ImClone's  delivery  of its  notice, such  number of copies of the  amended  or
supplemental registration  statement or prospectus  as reasonably  requested by
High River.

                (iv) Any registration statement filed pursuant to
this Section 8(a) shall be prepared in  accordance  with the requirements  of a
form for registration  promulgated by the United States Securities and Exchange
Commission (the  "Commission")  under the Act that shall be both permissible by
its terms for use in connection with the method of distribution contemplated by
High River and if the proposed method of distribution  shall be an underwriting
of the  Option  Shares,  then,  in the  opinion of  the  managing  underwriter,
appropriate  to such method of  distribution. ImClone shall pay the cost of the
registration  statements  filed under this Section 8(a)(excluding  underwriting
discounts,  selling  commissions  and transfer  taxes relating to the shares of
ImClone  Common  Stock owned by High  River), and the fees and expenses of High
River's  counsel in an amount not to exceed $20,000 per registration  statement
and $50,000 in the aggregate for all registration statements.

                  b.  ImClone  shall use its best efforts to qualify the Option
Shares  covered  by any  registration  statement for offer  and sale  under the
securities or "Blue Sky" laws of such states of the United States of America as
High River or any underwriter  may reasonably request;  provided,  that ImClone
shall not be  required in  connection  therewith or as a  condition  thereto to
qualify to do  business,  to subject  itself to general  taxation  or to file a
general consent to service of process in any such states.



<PAGE>




                  c. ImClone  shall be permitted to withdraw  from registration
the  offering  and  sale  of  any  of  the  Option  Shares registered  under  a
registration statement that are not sold prior to cessation of the distribution
thereof, by the underwriter in the case of an underwritten  sale or within nine
(9) months after the effective date of such registration  statement in the case
of  a  sale  on a  national  securities exchange  or  through  brokers  in  the
over-the-counter market.

                 d. If, pursuant to the provisions of this  Agreement,  ImClone
shall register under the Act shares of ImClone Common Stock held by High River,
ImClone agrees:

                           i.       As soon as practicable after the effective
date  of the registration  statement  relating  to  such  shares  and  for  the
applicableperiod thereafter during which a prospectus may be required by law to
be delivered in connectionwith the sales by an underwriter with respect to such
shares,  and in the case of a registration  for sale on a  national  securities
exchange  or  through  brokers in the  over-the-counter  market for up to eight
months  after such  effective date if by law  required  for such  delivery,  to
furnish the managing underwriter with respect to such underwritten  public sale
and to High  River with  such  number  of  copies  of each of the  registration
statement  and the prospectus  relating to the shares of ImClone  Common  Stock
covered  thereby as such managing  underwriter  and High River may from time to
time reasonably request;

                          ii.      To notify High River, as soon as practicable
after  it  receives notification  thereof,  of the  time  when  a  registration
statement has become effective or any supplement to any prospectus forming part
of such registration statement has been filed;

                           iii.    To notify High River promptly of any request
by the Commission for the amendment or supplementation of a
registration statement or prospectus, or for additional
information;

                           iv.      To prepare and file with the Commission
promptly upon the request of High River, any amendment of, or supplement  to, a
registration  statement or prospectus relating to information  respecting  High
River  which,  in the  opinion of counsel to High  River, may be  necessary  or
advisable in connection with the distribution of the registered shares; and

                           v.       To advise High River promptly in the event
that it receives notice or obtains knowledge of the issuance of a stop order by
the Commission  suspending the effectiveness of any such registration statement
or of the  initiation  or  threat of any  proceeding  for that  purpose, and to
promptly  use its best efforts to prevent the issuance of any stop order and to
obtain the withdrawal of any stop order in the event that one is issued.




<PAGE>



                  e. The  registration rights granted to High River pursuant to
the terms of this Section 8 may not be transferred to or exercised by any other
entity,  other than to any permitted assignee of this Agreement as set forth in
Section 9(a) hereof.

                  f.       ImClone agrees that it will:

                           i.      To the extent permitted by applicable law,
indemnify and hold harmless High River,any of its officers, directors, and each
person who controls any such person within the meaning of the Act in connection
with any  registration  statement filed pursuant to this Agreement, against any
losses,  claims,  damages or  liabilities,  joint or several, to which any such
person may become subject,  whether under the Act or otherwise, insofar as such
losses,  claims, damages or liabilities (or actions in respect thereof):(A) are
caused by any untrue statement or alleged untrue statement of any material fact
contained in any registration statement under which any shares of ImCloneCommon
Stock were,  pursuant to any of the  provisions  of this  Agreement, registered
under the Act,  any  prospectus  contained  therein,  any  amendment thereof or
supplement  thereto or any documents incorporated  by reference into any of the
foregoing;  or (B) are  caused by the omission  or  alleged  omission  to state
therein 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; and

                           ii.      Reimburse High River, its officers,
directors,  and each such  controlling  person for any legal or other  expenses
reasonably  incurred by them in connection with investigating  or defending any
such loss, claim,  damage, liability or action arising under clause (i) of this
Section 8(f).

The parties  agree that ImClone will not be liable under clauses (i) or (ii) of
Section  8(f) to the  extent  that any such  loss, claim,  damage,  expense  or
liability arises out of, or is based upon, an untrue statement,  alleged untrue
statement,  omission  or  alleged  omission  so made in  reliance  upon  and in
conformity with written information furnished by,or on behalf of, High River or
the person seeking  indemnification  specifically for use in the preparation of
such registration statement or prospectus contained therein oramendment thereof
or supplement  thereto; or the failure of High River to fulfill its obligations
to ImClone under clause(i) of Section 8(g). In addition, the parties agree that
ImClone will not be liable under clauses(i) or (ii) of Section 8(f) for amounts
paid in  settlement of any loss,  claim, damage,  liability,  or action if such
settlement is effected  without the consent of ImClone (which consent shall not
be unreasonably withheld); provided, that upon the receipt by ImClone of notice
of any claim  referred to in Section 8(f), ImClone shall have delivered to High
River proof acceptable to High River in itssole discretion that ImClone has the
financial  ability to discharge its  indemnification obligation with respect to
such claim.



<PAGE>



                  g.       High River agrees:

                           i.       If High River shall request registration as
provided  herein,  it  shall  furnish  to  ImClone  such information  as may be
reasonably  requested by ImClone in connection with such registration  and will
cooperate to cause the registration statement to become effective as aforesaid;

                           ii.     To the extent permitted by applicable law,to
indemnify  and hold  harmless  ImClone, each of its  directors  and each of its
officers who have signed any registration statement,  and each person,  if any,
who controls ImClone within the meaning of the Act, against any losses, claims,
damages or liabilities,  joint or several (or actions in respect  thereof): (A)
caused by any untrue statement or alleged untrue statement of any material fact
contained in any registration statement under which any sharesof ImClone Common
Stock were,  pursuant to any of the  provisions  of this  Agreement, registered
under the Act, any prospectus contained in such registration  statement, or any
amendment  thereof  or  supplement  thereto;  or (B) caused by any  omission or
alleged  omission to state a material  fact  required to be stated  therein, or
necessary to make the statement contained therein not misleading in lightof the
circumstances  under which they were made; in each case to the extent, but only
to the  extent,  that such  untrue  statement  or alleged  untrue  statement or
omission,  or alleged omission,  was so made in reliance upon,and in conformity
with,  written   information   furnished  by,  or  on  behalf  of, High  River,
specifically  for use in the  preparation  of  such  registration statement  or
prospectus  contained therein or amendment thereof or supplement thereto, or is
attributable to High River's  failure to carry out its obligations under clause
(i) of this Section 8(g); and

                 iii. That it will reimburse any legal or other
expenses  reasonably  incurred  by ImClone  or any such  director, officer,  or
controlling  person in connection with investigating or defending any suchloss,
claim,  damage,  liability or action  arising under clause (ii) of this Section
8(g).

                  h. Promptly after receipt by an indemnified party pursuant to
the  provisions  of Sections 8(f) or 8(g) of notice of the commencement  of any
action involving a claim referred to in such Sections,  such indemnified  party
will  notify  the  indemnifying  party of the  commencement thereof  if a claim
thereto  is to be made  against  the  indemnifying  party; provided,  that  the
omission so to notify the indemnifying  party shall not relieve an indemnifying
party from any  liability that it may have to any  indemnified  party under the
provisions of this  Agreement unless the failure to so notify the  indemnifying
party shall have materially prejudiced its ability to defend such action.In the
event that any such action is brought against any indemnified party and it duly
notifies the indemnifying  party of the commencement  thereof, the indemnifying
party will be entitled to  participate  in, and,to the extent that it may wish,
jointly with any other indemnifying party, similarly notified, to assume the



<PAGE>



defense of such action, with counsel reasonably satisfactory tosuch indemnified
party; and after notice from the indemnifying party tosuch indemnified party of
its election so to assume the defense of such  action, the  indemnifying  party
will not be liable  to such  indemnified  party for any legal or other expenses
subsequently  incurred by such indemnified party in connection with the defense
of such action other than reasonable costs of investigation.

                  i. Notwithstanding anything to the contrary set forth herein,
if ImClone at any time shall  register  shares of ImClone Common Stock for sale
for its own account,  High River shall, upon the written request of ImClone,not
publicly sell,  make any short sale of, grant any option for the purchase of,or
otherwise  dispose  of any shares of ImClone  Common  Stock owned by High River
(other than those  included  in such  registration)  without the prior  written
consent of  ImClone,  to the extent and for the period (not exceeding  60 days)
that all  directors and officers of ImClone  (other than directors and officers
holding  not more than  25,000  shares of Common  Stock(as  adjusted  for stock
dividends,  stock  splits,  combinations  of shares, or similar  events) in the
aggregate) are subject to the same restriction.

         9.       Miscellaneous.

                           a.       Assignment.  This Agreement shall not be
assigned by ImClone. High River may assign this Agreement and all of its rights
hereunder  to any affiliate  or to its  successor  as a result  of any  merger,
consolidation  or transfer  of all or  substantially  all of its  assets.  This
Agreement  shall be  binding  on each of  High  River  and  ImClone  and  their
respective successors and permitted assigns.

                         b.       Entire Agreement; Amendments.  This Agreement
states the entire agreement  reached between the parties hereto with respect to
the transactions contemplated  hereby and may not be amended or modified except
by written instrument duly executed by the parties hereto. Any and all previous
or contemporary agreements and understandings between the parties regarding the
subject  matter hereof,  whether  written  or  oral,  are  superseded  by  this
Agreement.

                           c.       Notices.  All notices and other
communications given or made  pursuant  hereto shall be in writing and shall be
deemed to have been duly given or made upon  receipt,  if made or given by hand
delivery,  telecopier or facsimile  transmission,  or Federal  Express or other
reputable overnight courier service, or upon receipt by registered or certified
mail(postage prepaid, return receipt requested), at the following addresses (or
at such other address for a party as shall be specified by like notice):

                           i.       if to High River:

                           High River Limited Partnership



<PAGE>



                           100 South Bedford Road
                           Mt. Kisco, New York 10549
                           Attn:            Carl C. Icahn

(or such other address as may have been furnished in writing by
High River to ImClone)

                           with a copy to:

                           Gordon Altman Butowsky Weitzen Shalov & Wein
                           114 West 47th Street
                           New York, New York 10036
                           Attention:  Marc Weitzen, Esq.

                           ii.      if to ImClone:

                           ImClone Systems Incorporated
                           180 Varick Street
                           New York, New York 10014
                           Attn:            Samuel D. Waksal, Ph.D.
                                            President and Chief Executive
                                            Officer

(or such other address as may have been furnished to High River
in writing by ImClone)

                           with a copy to:

                           Howard, Darby & Levin
                           1330 Avenue of the Americas
                           New York, New York 10019
                           Attn:            Lawrence A. Darby, III, Esq.


                  d.  Governing  Law. This  Agreement shall be governed by, and
interpreted  under, the laws of the State of New York  applicable  to contracts
made and to be performed therein without regard to conflicts of law principles.

                  e.Counterparts. This Agreement may be executed in one or more
counterparts, each of which  shall be an  original,  but all of which  together
shall constitute one and the same agreement.It shall not be necessary in making
proof of this  Agreement  or any  counterpart hereof to account  for any of the
other counterparts.

                  f.       Effect of Headings.  The section headings herein
are for convenience only and shall not affect the construction
hereof.

                  g.       Severability.  Any provision of this Agreement
that may be prohibited or unenforceable in law or equity in any
jurisdiction shall, as to such jurisdiction, be ineffective to
the extent of such prohibition or unenforceability without
invalidating the remaining provisions thereof.  Any such



<PAGE>



prohibition  or  unenforceability  in any jurisdiction  shall not invalidate or
render  unenforceable  such provision in any other jurisdiction.  To the extent
permitted by law,the parties hereby waive any provision of law that renders any
provision of this Agreement  prohibited  or  unenforceable  in any respect.  In
addition, in the eventof any such prohibition or unenforceability,  the parties
agree that it is their intention and agreement that any such provision which is
held or  determined to be  prohibited  or  unenforceable,  as  written,  in any
jurisdiction  shall nonetheless  be in force and binding to the fullest  extent
permitted by law of such jurisdiction as though such provision had been written
in such a manner and to such an extent as to be enforceable  therein  under the
circumstances.

                  h. Survival of Representations, Warranties and Covenants. All
of the  representations,  warranties  and covenants contained in this Agreement
shall survive the execution and delivery of this Agreement.

                  i. Remedies Not Exclusive;  Specific Performance.  The rights
and remedies in this Agreement shall be deemed to be in addition to, and not in
limitation  of, all other rights and remedies that would otherwise be available
to the parties hereto including, without limitation,  any actions for breach of
contract. The exercise or attempted exercise by either party of any such rights
or remedies shall not preclude the simultaneous or later exercise by such party
of any or all other  such  rights or remedies  available  at law,  in equity or
otherwise.  No course of dealing by either  party, or any  delay,  omission  or
failure of any party in  exercising  or enforcing any rights or remedies  under
this  Agreement  shall operate as a waiver of such right or remedy or any other
rights or remedies of such party.The parties agree that each party, in addition
to all other remediessuch party may have hereunder, at law or otherwise,  shall
have the right to enforce such party's rights under this Agreement by an action
or actions for specific  performance, injunction or other appropriate equitable
remedies. In furtherance and not in limitation of the foregoing, ImClone agrees
that in the event of its  breach of the  provisions of  Section 8 hereof,  High
River shall be  entitled,  in addition to all other remedies to which it may be
entitled,  to temporary or permanent injunctive or mandatory relief or specific
performance without the necessity of proving damages.

                  j.  Binding Effect.  This Agreement and the rights and
interests granted herein shall be binding upon, and shall inure
to the benefit of, the parties and their



<PAGE>



respective successors (whether by merger or otherwise) and
permitted assigns.

                IN WITNESS  WHEREOF,  High River and ImClone  have caused this
Agreement to be executed as of the date first above written by their respective
officers thereunto duly authorized.

                                                  IMCLONE SYSTEMS INCORPORATED

                                               By:      _______________________
                                                     Name:
                                                     Title:

                                                 HIGH RIVER LIMITED PARTNERSHIP
                                            By:      RIVERDALE INVESTORS CORP.,
                                                          INC., General Partner

                                            By:      _________________________
                                                     Name:
                                                     Title:


(Signature Page to Option from ImClone to High Riverfor up to 150,000 shares of
ImClone Common Stock)



<PAGE>




                                                     EXHIBIT 3

                                                 OPTION AGREEMENT


         OPTION AGREEMENT dated as of April 27, 1995 (the "Agreement"), between
ImClone Systems Incorporated, a Delaware Corporation ("ImClone"),and High River
Limited Partnership, a Delaware limited partnership ("High River").

         WHEREAS,  pursuant to an option  agreement of even date,High River has
agreed to grant to ImClone a certain  option  (the "Cadus  Option") pursuant to
which High River will sell to ImClone,  upon the terms and conditions contained
therein,  1,050,000  shares of Common  Stock,  $.001  par value per share,  and
2,188,184  shares of Series A  Preferred  Stock,  $.001 par value per share, of
Cadus Pharmaceutical Corporation, a Delaware corporation;

         WHEREAS,  as  consideration  for the  grant by High River of the Cadus
Option, ImClone has agreed to grant to High River the option described herein;

         NOW THEREFORE, in consideration of the mutual covenants and agreements
set forth herein, the parties hereto agree as follows:

                  1. Grant of Option.  ImClone  hereby  grants to High River an
option (the "Option")to purchase, on the terms and conditions set forth herein,
300,000 shares of common stock of ImClone, par value $.001 per share  ("ImClone
Common  Stock")  for a price per share equal to $0.50 (the  "Exercise  Price"),
subject to adjustment  pursuant to Section 4 hereof (the "Option  Shares"). The
Option  granted  hereby shall  terminate and expire at 5:00 p.m., New York City
time, on April 27, 2000 (the "Expiration Date").

                  2. Exercise of Option. High River may exercise this Option in
whole or in part at any time from timeto time commencing on the date hereof and
continuing through the Expiration Date.

                  3.       Exercise of Option.

                           a.     To exercise the Option, High River shall give
written  notice to ImClone of such exercise,  which  notice  shall  specify the
number of Option Shares to be purchased and the place, date and time designated
by High  River for the  closing of such  purchase, which date shall not be less
than 5  business  days nor more  than 15  business days  after the date of such
notice.  Notwithstanding  any provision of this Agreement to the contrary,  the
giving of any  exercise  notice by High River shall not obligate  High River to
consummate any purchase hereunder.

                           b.       At each closing:(i) High River will (x) pay
to ImClone, by delivery of a certified or bank cashier's check
payable in immediately available funds, an amount equal to the

                                                       -26-

<PAGE>



product of the Exercise  Price and the number of Option Shares specified in the
applicable  exercise  notice and (y) provide to ImClone a letter signed by High
River to the effect that (A) High River is acquiring such Option Shares for its
own  account,  and not with a view to, or for  resale in connection  with,  the
distribution   thereof,  and  that  High  River  has  no  present intention  of
distributing or reselling such shares and(B) High River agrees that such Option
Shares shall not be sold or transferred unless either (1) they first shall have
been  registered  under the Securities Act of 1933, as amended (the "Act"), and
applicable  state  securities or blue sky laws or (2) ImClone  first shall have
been furnished with an opinion of legal counsel acceptable in form andsubstance
to ImClone (in its sole  discretion)to the effect that such sale or transfer is
exempt from the foregoing registration requirement and (ii)ImClone will deliver
to High River one or more  certificates,  registered in High River's name or in
the name of any  nominee  designated  by High  River, representing  such Option
Shares.

                  4.       Adjustments

                           a.      In case after the date hereof, ImClone shall
(i)  pay a  dividend  or make a distribution  on  ImClone  Common  Stock,  (ii)
subdivide the outstanding shares of ImClone Common Stock into a larger numberof
shares of ImClone Common Stock, (iii) combine the outstanding shares of ImClone
Common  Stock into a smaller number of shares of ImClone  Common  Stock or (iv)
increase or decrease the numberof shares of ImClone Common Stock outstanding by
reclassification  of the ImClone Common Stock, then the number of Option Shares
purchasable upon exercise of the Option  immediately after the happening ofsuch
event shall be  adjusted  so that High River  shall be entitled to receive upon
exercise of this  Option,  the number of shares of ImClone  Common Stock and,in
the case of a dividend or  distribution  other than in shares of ImClone Common
Stock, the cash, securities or other property so dividended or distributed,that
High  River  would  have  owned or have been  entitled  to  receive immediately
following  the  happening of such event,  had the Option been exercised in full
immediately  prior  thereto  (or, in the case of a dividend or distribution  on
ImClone Common Stock,  immediately  prior to the record date therefor), and the
Exercise  Price  for  the  Option  shall  be  adjusted  in  inverse  proportion
(calculated  to the nearest .001 of a cent). If the amount of any adjustment of
the Exercise Price required pursuant to this Section 4(a)would be less than two
percent  (2%) of the  Exercise  Price in effect at the time such  adjustment is
otherwise  so required  to be made,  such  amount  shall be carried forward and
adjustment  with  respect  thereto  made at the  time of and  together with any
subsequent  adjustment which,  together with such amount and any otheramount or
amounts so carried  forward,  shall  aggregate at least two percent(2%) of such
Exercise  Price.  An adjustment  made pursuant to this Section 4(a)shall become
effective  immediately after the effective date, retroactive to the record date
therefore in the case of a dividend or distribution on shares of ImClone Common
Stock, and shall become effective immediately after the effective



<PAGE>



date in the case of a subdivision, combination or
reclassification of ImClone Common Stock.

                           b.       In case ImClone after the date hereof (i)
shall  consolidate  with or merge  into any other  person  and shall not be the
continuing or surviving  corporation of such consolidation  or merger,  or (ii)
shall  permit any other  person to  consolidate with or merge into  ImClone and
ImClone shall be the continuing or surviving person but,in connection with such
consolidation or merger,ImClone Common Stock shall be changed into or exchanged
for stock or other securities of any other person or cash or any otherproperty,
or (iii) shall transfer all or substantially all of its properties or assets to
any  other   person  or  (iv)   shall   effect a  capital   reorganization   or
reclassification of ImClone Common Stock,then proper provision shall be made so
that  High  River,  upon  any  exercise  of the Option  at any time  after  the
consummation of such transaction,shall be entitled to receive (at the aggregate
Exercise Price in effect at the time of such consummation for all Option Shares
issuable upon such exercise immediately prior to such consummation), in lieu of
the ImClone Common Stockissuable upon such exercise prior to such consummation,
the amount of  securities, cash or other  property  to which  High River  would
actually  have been entitled as a shareholder  upon such  consummation  if High
River had exercised the Option immediately prior thereto.After the consummation
of any such  transaction, "Option Shares" shall refer to such other securities,
cash or other property.

                           c.       Notwithstanding any provision in this
Agreement  to the  contrary, ImClone  will not effect  any of the  transactions
described in clauses(i) through (iv) of Section  4(b) hereof  unless,  prior to
the consummation thereof,each person (other than ImClone) which may be required
to deliver  any stock, securities,  cash or property  upon the  exercise of the
Option as provided herein shall assume,by written  instrument  delivered to and
reasonably  satisfactory  to High River, the  obligations of ImClone under this
Agreement.

                  5.  Representations and Warranties of ImClone. ImClone hereby
represents and warrants to High River as follows:

                           a.       Due Authorization, etc.  ImClone has all
necessary  corporate power and authority to execute and deliver this Agreement.
The  execution  and delivery  of this  Agreement  and the  consummation  of the
transactions contemplated  hereby have been duly  authorized  by all  necessary
corporate action on the part of ImClone.  This Agreement has been duly executed
and  delivered by a duly authorized  officer of ImClone,  constitutes  a legal,
valid and binding agreement of ImClone and is  enforceable  against  ImClone in
accordance with its terms, except as such  enforceability may be limited by (i)
the effect of bankruptcy,insolvency, reorganization, moratorium, marshalling or
other  similar laws now or hereafter  in effect  relating to or  affecting  the
rights and remedies of creditors generally and (ii) general



<PAGE>



principles of equity, whether such enforceability is considered
in a proceeding in equity or at law.

                           b.       Option Shares. All of the Option Shares to
be acquired upon exercise of the Option shall be duly and validly issued, fully
paid  and  non-assessable  and  shall be free and  clear of any  liens, claims,
charges,  rights of others,  security interests, options or encumbrances of any
nature,  including preemptive rights. ImClone has taken all necessary corporate
and other  action to  authorize, to reserve and to permit it to sell and issue,
and at all times from the date hereof until such time as ImClone'sobligation to
sell and deliver shares of ImClone Common Stock hereunder terminates, will have
reserved for issuance upon exercise of the Option, the maximum number of Option
Shares that High River has the right to purchase hereunder.

                           c.       No Conflicts; No Consents.  Neither the
execution  and  delivery by ImClone of this  Agreement nor the  performance  by
ImClone of its  obligations  hereunder  will: (i) violate or conflict  with any
provision of ImClone's  Certificate of Incorporation or By-Laws,in each case as
in effect on the date hereof and on the date of any closing hereunder;(ii) with
or without the giving of notice or the passage of time, or both, violate, or be
in conflict with, or permit the  termination  of,or constitute a default under,
or cause the acceleration of the maturity of, any agreement, debt or obligation
of any  nature of  ImClone  or to which  ImClone is a party or it or any of its
properties is bound;  (iii) require the consent of any party to any  agreement,
instrument  or  commitment to which ImClone is a party or to which it or any of
its  properties  is bound; (iv)  violate  any  statute or law or any  judgment,
decree,  order,  regulation or  rule  of any  court,  regulatory  authority  or
governmental  agency or authority to which ImClone or any of its  properties is
subject;  or(v) result in the creation of any lien or other  encumbrance on its
assets. No consent,  approval or  authorization  of, or declaration,  filing or
registration with,any regulatory  authority or governmental agency or authority
is required to be made or obtained by ImClone in connection with the execution,
delivery and  performance of this  Agreement, the performance by ImClone of its
obligations  hereunder  or the con  summation of the transactions  contemplated
hereby.  ImClone  is  not a  party  to  any  material contract,  commitment  or
agreement, nor is ImClone subject to, or bound by,any order, judgment,  decree,
law, statute,  ordinance,  rule,  regulation or otherrestriction of any kind or
character, which would prevent ImClone from entering into this Agreement orfrom
consummating the trans actions contemplated hereby.

                  6.  Representation  and  Warranty  of High  River. High River
hereby represents and warrants to ImClone as follows:

                           a.       Due Authorization, etc. High River has full
power and authority to execute and deliver this Agreement.  The
execution and delivery of this Agreement and the consummation of



<PAGE>



the transactions  contemplated hereby have beenduly authorized by all necessary
partnership  action  on the part of High  River. This  Agreement  has been duly
executed and delivered by a duly authorized signatory of High River,constitutes
a legal,  valid and binding  agreement of High River and is enforceable against
High River in accordance with its terms,  except as such  enforceability may be
limited by (i) the effect of bankruptcy, insolvency, reorganization,moratorium,
marshalling  or other  similar laws now or  hereafter  in effect relating to or
affecting  the rights and  remedies  of  creditors  generally and (ii)  general
principles of equity,  whether such enforceability is considered in aproceeding
in equity or at law.

                           b. Investment.  High River is acquiring this
Option for its own account for investment and not with a view to, orfor sale in
connection with, any  distribution  thereof,  nor with any present intention of
distributing  or selling the same; and High River has no presentor contemplated
agreement,  undertaking,  arrangement,  obligation,  indebtedness or commitment
providing for the disposition thereof.  High River is aware thatthis Option and
the Option  Shares are not being  registered  under the Act or under applicable
state securities or blue sky laws, and that the certificate(s) representing the
Option Shares will bear the following legend:

                 "THE  SECURITIES  REPRESENTED  BY THIS  INSTRUMENT  HAVE  BEEN
                 ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE
                 SECURITIES  ACT  OF  1933  (THE  "ACT")  OR  APPLICABLE  STATE
                 SECURITIES OR BLUE SKY LAWS.  THE  SECURITIES  REPRESENTED  BY
                 THIS INSTRUMENT MAY NOT BE OFFERED FOR SALE,  SOLD,  DELIVERED
                 AFTER  SALE,  TRANSFERRED,  PLEDGED  OR  HYPOTHECATED  IN  THE
                 ABSENCE OF (1) AN EFFECTIVE  REGISTRATION  STATEMENT  COVERING
                 SUCH SECURITIES  UNDER THE ACT AND APPLICABLE STATE SECURITIES
                 OR BLUE SKY LAWS OR (2) AN  OPINION  OF  COUNSEL TO THE EFFECT
                 THAT  SUCH  REGISTRATION  IS NOT  REQUIRED  UNDER  THE ACT AND
                 APPLICABLE  STATE  SECURITIES OR BLUE SKY LAWS,  WHICH OPINION
                 SHALL BE  ACCEPTABLE  IN FORM AND  SUBSTANCE TO THE COMPANY IN
                 ITS SOLE DISCRETION."

                 7. ImClone Covenants.  ImClone covenants and agrees that, from
the date hereof through the Expiration Date, it will take all action  necessary
so that each of ImClone's  representations and warranties  contained  herein is
true,  complete  and correct at all times until the  termination  of  ImClone's
obligation to sell and deliver shares of ImCloneCommon Stock hereunder.


                  8.       Registration Under Securities Act.




<PAGE>



                  a. (i) Upon written request by High River, ImClone will cause
to be prepared and filed a registration statement under the Actrelating to such
number of Option Shares as may be designated by High River and ImClone will use
its best efforts  to cause such  registration  statement  to become  effective;
provided, however,  that High River  shall be required to register no less than
150,000 Option Shares under any such registration  statement.  High River shall
have the right to select  the  underwriter or  underwriters  who shall make the
offering,  if it is to be  underwritten, but  High  River's  selection  must be
approved by ImClone,which approval shall not be unreasonably withheld.  ImClone
shall  keep such registration  statement  effective  until it is  permitted  to
withdraw  the same pursuant to Section  8(c).  Notwithstanding  anything to the
contrary set forth herein, ImClone may delay the filing or effectiveness of any
registration  statement for a  period  of up to 120  days  after  the date of a
request for registration pursuant to this Section8(a)(i) if at the time of such
request ImClone is engaged in a firm commitment underwritten public offering.

                  (ii) If at any time when High River owns any
shares of ImClone Common Stock acquired pursuant to the exerciseof this Option,
ImClone  effects a  registration  of ImClone Common Stock for itsown account or
for the  account of any other  shareholder  of ImClone  in connection  with the
public offering of such ImClone Common Stock (other than onForm S-4 or Form S-8
or any  successor  form),  it shall  allow  High  River to participate  in such
registration;  provided,  however, if the managing underwritersin such offering
advise  ImClone in writing that in their opinion the number ofshares of ImClone
Common Stock  requested to be included in such  registration exceeds the number
which can be sold in such offering at the proposed offering price,the number of
shares of  ImClone  Common  Stock  owned by High  River to be included  in such
registration shall be reduced to such number that will make theaggregate shares
of ImClone  Common Stock so registered  not in excess of the numberof shares of
ImClone Common Stock that the  underwriters  believe can be soldat the proposed
price.  In connection  with any offering  involving an  underwriting of ImClone
Common Stock for ImClone's account or for the account of any other shareholder,
ImClone  shall not be required  under this  subparagraph  (ii)to include any of
High River's ImClone Common Stock in such underwriting unlessHigh River accepts
the reasonable terms of the underwriting as agreed upon byImClone or such other
shareholder,  accepts  such  underwriters  selected  by  ImClone or such  other
shareholder  and  agrees to enter  into and  perform  its obligations  under an
underwriting  agreement,  in usual and customary form, with such  underwriters.
ImClone  shall be under no obligation  to complete any registration  of ImClone
Common  Stock it proposes to make and shall incur noliability to High River for
its failure to do so (and its failure to complete the registration of shares of
ImClone Common Stock included in such  registration by High River in connection
therewith).




<PAGE>



                (iii) If, during the period when any registration
statement  covering  shares  of  ImClone  Common  Stock owned by High  River is
effective, any event occurs as a result of which theprospectus included in such
registration  statement, as then in effect,would include an untrue statement of
a material fact or omit to state a materialfact required to be stated  therein,
or necessary in order to make the statementsmade not misleading in light of the
circumstances  then  existing,  or it shallbe necessary to amend or  supplement
such  prospectus to comply with applicable law,  ImClone will forthwith  notify
High River  thereof and, at High River's request,  ImClone will (a) prepare and
file under the Act such  amendments and supplements as may be necessary to keep
available a prospectus  covering such registered stock meeting the requirements
of the Act, and (b) furnish to the underwriters, if any, and to High River such
number of copies of each of the registrationstatement and prospectus as amended
or  supplemented  as may  reasonably be requested from time to time;  provided,
however,  that once High River is  notified by ImClone of the happening  of any
event of the kind described above in this  subparagraph (iii),  High River will
thereafter  immediately   discontinue  the  distribution of  such  registration
statement or prospectus and the  disposition of ImCloneCommon Stock pursuant to
such  registration  statement  or  prospectus  untilsuch time as High River has
received  from  ImClone  a  copy  or  copies  of  the amended  or  supplemental
registration  statement or prospectus  contemplated by this subparagraph (iii),
and if so directed by ImClone in its notice, High River shall deliver toImClone
all copies, other than permanent file copies, then in High River'spossession of
the  registration  statement or prospectus  covering such ImClone Common Stock;
provided,  further,  that ImClone shall deliver to High River,within 15 days of
ImClone's  delivery  of its  notice,  such  number of copies of the amended  or
supplemental  registration  statement or prospectus  as reasonably requested by
High River.

                (iv) Any registration statement filed pursuant to
this Section 8(a) shall be prepared in  accordance  with the requirements  of a
form for registration  promulgated by the United States Securities and Exchange
Commission (the  "Commission")  under the Act that shallbe both  permissible by
its terms for use in connection with the method of distribution contemplated by
High River and if the proposed method of  distribution  shall be anunderwriting
of the  Option  Shares,  then,  in the  opinion  of  the  managing underwriter,
appropriate  to such method of  distribution. ImClone shall pay the cost of the
registration  statements  filed under this Section 8(a)(excluding  underwriting
discounts,  selling  commissions  and transfer  taxes relating to the shares of
ImClone  Common  Stock owned by High  River),  and thefees and expenses of High
River's  counsel in an amount not to exceed $20,000 per registration  statement
and $50,000 in the aggregate for all registration statements.

                  b.  ImClone  shall use its best efforts to qualify the Option
Shares  covered  by any  registration  statement for offer  and sale  under the
securities or "Blue Sky" laws of such states of



<PAGE>



the United  States of America as High River or any underwriter  may  reasonably
request; provided, that ImClone shall not be requiredin connection therewith or
as a condition  thereto to qualify to do business, to subject itself to general
taxation or to file a general consent to service ofprocess in any such states.

                  c. ImClone  shall be permitted to withdraw from  registration
the  offering  and  sale  of  any  of  the  Option  Shares registered  under  a
registration  statement that are not sold prior to cessationof the distribution
thereof,  by the underwriter in the case of an underwritten sale or within nine
(9) months after the effective date of such  registration statement in the case
of  a  sale  on a  national  securities  exchange  or through  brokers  in  the
over-the-counter market.

                  d. If, pursuant to the provisions of this Agreement,  ImClone
shall  register under the Act shares of ImClone Common Stock held byHigh River,
ImClone agrees:

                           i.       As soon as practicable after the effective
date  of the  registration  statement  relating  to  such  shares and  for  the
applicable period thereafter during which a prospectusmay be required by law to
be delivered in connection with the sales by anunderwriter with respect to such
shares,  and in the case of a  registration for sale on a  national  securities
exchange  or  through  brokers  in the over-the-counter  market for up to eight
months  after such  effective  date if by law required  for such  delivery,  to
furnish the managing  underwriter with respectto such underwritten  public sale
and to High  River  with  such  number  of copies  of each of the  registration
statement  and the  prospectus  relating tothe shares of ImClone  Common  Stock
covered  thereby as such  managing  underwriter and High River may from time to
time reasonably request;

                           ii.      To notify High River,as soon as practicable
after  it  receives  notification  thereof,  of the  time when  a  registration
statement has become effective or any supplement to any prospectus forming part
of such registration statement has been filed;

                           iii.    To notify High River promptly of any request
by the Commission for the amendment or supplementation of a
registration statement or prospectus, or for additional
information;

                           iv.      To prepare and file with the Commission
promptly upon the request of High River, any amendment of, or supplement  to, a
registration  statement or prospectus relating to information  respecting  High
River  which,  in the  opinion of counsel to High River,  may be  necessary  or
advisable in connection with the distribution of the registered shares; and

                           v.       To advise High River promptly in the event
that it receives notice or obtains knowledge of the issuance of a
stop order by the Commission suspending the effectiveness of any



<PAGE>



such registration statement or of the initiation or threatof any proceeding for
that  purpose,  and to promptly  use its best efforts toprevent the issuance of
any stop order and to obtain the  withdrawal of any stoporder in the event that
one is issued.

                  e. The  registration  rights granted toHigh River pursuant to
the terms of this Section 8 may not be  transferred toor exercised by any other
entity,  other than to any permitted  assignee of thisAgreement as set forth in
Section 9(a) hereof.

                  f.       ImClone agrees that it will:

                           i.       To the extent permitted by applicable law,
indemnify and hold harmless High River, any of its officers,directors, and each
person who controls any such person  within the meaning of theAct in connection
with any  registration  statement filed pursuant to this Agreement, against any
losses,  claims,  damages or  liabilities,  joint or several, to which any such
person may become subject,  whether under the Act or otherwise, insofar as such
losses,  claims, damages or liabilities (or actions in respect thereof):(A) are
caused by any untrue  statement or alleged untrue statement of any materialfact
contained in any registration statement under which any shares of ImCloneCommon
Stock were,  pursuant to any of the  provisions  of this  Agreement, registered
under the Act,  any  prospectus  contained  therein,  any  amendment thereof or
supplement  thereto or any documents  incorporated  by reference intoany of the
foregoing;  or (B) are  caused by the  omission  or  alleged  omission to state
therein a material fact  required to be stated  therein or necessaryto make the
statements therein in light of the circumstances  under which theywere made not
misleading; and

                           ii.      Reimburse High River, its officers,
directors,  and each such  controlling  person  for any legal or other expenses
reasonably  incurred by them in connection with  investigating  ordefending any
such loss, claim,  damage,  liability or action arising under clause(i) of this
Section 8(f).

The parties  agree that ImClone will not be liable under  clauses(i) or (ii) of
Section  8(f) to the  extent  that any such  loss,  claim,  damage, expense  or
liability arises out of, or is based upon, an untrue  statement, alleged untrue
statement,  omission  or  alleged  omission  so made  in  reliance upon  and in
conformity with written information furnished by, or on behalf of,High River or
the person seeking  indemnification  specifically  for use in thepreparation of
such registration statement or prospectus contained therein oramendment thereof
or supplement  thereto;  or the failure of High River to fulfillits obligations
to ImClone under clause (i) of Section 8(g). In addition, theparties agree that
ImClone will not be liable under clauses (i) or (ii) of Section 8(f)for amounts
paid in  settlement of any loss,  claim,  damage,  liability, or action if such
settlement is effected  without the consent of ImClone (which consent shall not
be unreasonably withheld); provided, that upon the receipt by



<PAGE>



ImClone of notice of any claim  referred to in Section 8(f), ImClone shall have
delivered to High River proof  acceptable  to High River in itssole  discretion
that  ImClone  has  the  financial  ability  to  discharge  its indemnification
obligation with respect to such claim.

                  g.       High River agrees:

                           i.      If High River shall request registration as
provided  herein,  it  shall  furnish to  ImClone  such  information  as may be
reasonably  requested by ImClone inconnection with such  registration  and will
cooperate to cause the registrationstatement to become effective as aforesaid;

                           ii.     To the extent permitted by applicable law, to
indemnify  and hold  harmless  ImClone, each of its  directors  and each of its
officers who have signed any registration statement,  and each person,  if any,
who controls ImClone within the meaning of the Act,against any losses,  claims,
damages or liabilities,  joint or several(or actions in respect  thereof):  (A)
caused by any untrue  statement or alleged untrue statement of any materialfact
contained in any registration statement under which any shares of ImCloneCommon
Stock were,  pursuant to any of the  provisions  of this  Agreement, registered
under the Act, any prospectus contained in such registration  statement, or any
amendment  thereof  or  supplement  thereto;  or (B) caused by any omission  or
alleged  omission to state a material  fact  required to be stated therein,  or
necessary to make the statement contained therein not misleadingin light of the
circumstances  under which they were made; in each case to the extent, but only
to the  extent,  that such  untrue  statement  or alleged  untrue statement  or
omission,  or alleged omission,  was so made in reliance upon,and in conformity
with,  written   information   furnished  by,  or  on  behalf of,  High  River,
specifically  for use in the  preparation  of  such  registration statement  or
prospectus  contained therein or amendment thereof or supplement thereto, or is
attributable to High River's  failure to carry out its obligations under clause
(i) of this Section 8(g); and

                 iii. That it will reimburse any legal or other
expenses  reasonably  incurred  by ImClone  or any such  director, officer,  or
controlling  person in connection with investigating or defending any suchloss,
claim,  damage,  liability or action  arising  under clause (ii)of this Section
8(g).

                  h. Promptly after receipt by an indemnified party pursuant to
the  provisions  of Sections 8(f) or 8(g) of notice of the commencement  of any
action involving a claim referred to in such Sections,  such indemnified  party
will  notify  the  indemnifying  party of the  commencement thereof  if a claim
thereto  is to be made  against  the  indemnifying  party; provided,  that  the
omission so to notify the  indemnifying  party shall not relievean indemnifying
party from any  liability  that it may have to any  indemnified party under the
provisions of this  Agreement  unless the failure to so notify the indemnifying
party shall have



<PAGE>



materially  prejudiced its ability to defend such action. In the event that any
such action is brought  against any  indemnified  party andit duly notifies the
indemnifying party of the commencement  thereof,  theindemnifying party will be
entitled to  participate  in, and, to the extent that it may wish, jointly with
any other indemnifying party,  similarly notified, to assume the defenseof such
action,  with counsel  reasonably  satisfactory to such  indemnified party; and
after  notice  from  the  indemnifying  party to such  indemnified party of its
election so to assume the defense of such action,  the  indemnifying party will
not be  liable  to such  indemnified  party  for any  legal  or  other expenses
subsequently  incurred by such indemnified  party in connection withthe defense
of such action other than reasonable costs of investigation.

                  i. Notwithstanding  anything to the contrary setforth herein,
if ImClone at any time shall  register  shares of ImClone  CommonStock for sale
for its own account,  High River shall, upon the written requestof ImClone, not
publicly sell,  make any short sale of, grant any option for thepurchase of, or
otherwise  dispose  of any shares of ImClone  Common  Stock owned by High River
(other than those  included  in such  registration)  without the prior  written
consent of  ImClone,  to the extent and for the period (not exceeding  60 days)
that all  directors and officers of ImClone  (other than directors and officers
holding  not more than  25,000  shares of Common  Stock(as  adjusted  for stock
dividends,  stock  splits,  combinations  of shares, or similar  events) in the
aggregate) are subject to the same restriction.

         9.       Miscellaneous.

                           a.       Assignment.  This Agreement shall not be
assigned by ImClone.  High River may assign this Agreement andall of its rights
hereunder  to any  affiliate  or to its  successor  as a result of any  merger,
consolidation  or  transfer  of all or  substantially  all of its assets.  This
Agreement  shall  be  binding  on each of  High  River  and  ImClone and  their
respective successors and permitted assigns.

                           b.       Entire Agreement; Amendments. ThisAgreement
states the entire  agreement  reached between the parties heretowith respect to
the transactions  contemplated  hereby and may not be amended ormodified except
by written  instrument duly executed by the parties hereto. Anyand all previous
or contemporary  agreements and understandings between the partiesregarding the
subject  matter  hereof,  whether  written  or  oral,  are  superseded by  this
Agreement.

                           c.       Notices.  All notices and other
communications  given or made  pursuant  hereto shall be in writing andshall be
deemed to have been duly  given or made upon  receipt,  if made or givenby hand
delivery,  telecopier  or facsimile  transmission,  or Federal  Express orother
reputable  overnight courier service, or upon receipt by registered orcertified
mail (postage prepaid, return receipt requested), at the following



<PAGE>



addresses (or at such other address for a party as shall be
specified by like notice):

                           i.       if to High River:

                           High River Limited Partnership
                           100 South Bedford Road
                           Mt. Kisco, New York 10549
                           Attn:            Carl C. Icahn

(or such other address as may have been furnished in writing by
High River to ImClone)

                           with a copy to:

                           Gordon Altman Butowsky Weitzen Shalov &
                                      Wein
                           114 West 47th Street
                           New York, New York 10036
                           Attention:  Marc Weitzen, Esq.


                           ii.      if to ImClone:

                           ImClone Systems Incorporated
                           180 Varick Street
                           New York, New York 10014
                           Attn:            Samuel D. Waksal, Ph.D.
                                            President and Chief Executive
                                            Officer

(or such other address as may have been furnished to High River
in writing by ImClone)

                           with a copy to:

                           Howard, Darby & Levin
                           1330 Avenue of the Americas
                           New York, New York 10019
                           Attn:            Lawrence A. Darby, III, Esq.


                  d.  Governing  Law. This  Agreement shall be governed by, and
interpreted  under,  the laws of the State of New York applicable  to contracts
made and to be performed therein without regard to conflictsof law principles.

                  e. Counterparts. This Agreement may be executedin one or more
counterparts,  each of which  shall be an  original,  but all ofwhich  together
shall constitute one and the same agreement. It shall not be necessaryin making
proof of this  Agreement  or any  counterpart  hereof to account  forany of the
other counterparts.




<PAGE>



                  f.       Effect of Headings.  The section headings herein
are for convenience only and shall not affect the construction
hereof.

                  g.  Severability.  Any provision ofthis Agreement that may be
prohibited or unenforceable  in law or equity in any jurisdiction  shall, as to
such  jurisdiction,  be  ineffective  to  the  extent of  such  prohibition  or
unenforceability without invalidating the remaining provisions thereof.Any such
prohibition  or  unenforceability  in any  jurisdiction  shall notinvalidate or
render  unenforceable  such provision in any other  jurisdiction. To the extent
permitted by law, the parties hereby waive any provision of law thatrenders any
provision of this  Agreement  prohibited  or  unenforceable  in anyrespect.  In
addition, in the event of any such prohibition or unenforceability, the parties
agree that it is their  intention and agreement that any such provisionwhich is
held or  determined  to be  prohibited  or  unenforceable,  as  written, in any
jurisdiction  shall  nonetheless  be in force and binding to the fullest extent
permitted by law of such  jurisdiction as though such provision had beenwritten
in such a manner and to such an extent as to be  enforceable  therein under the
circumstances.

                  h. Survival of Representations, Warranties and Covenants. All
of the  representations,  warranties  and covenants contained in this Agreement
shall survive the execution and delivery of this Agreement.

                  i. Remedies Not Exclusive;  Specific Performance.  The rights
and remedies in this Agreement  shall be deemed to bein addition to, and not in
limitation  of, all other rights and remedies that would otherwise be available
to the parties hereto including,  without limitation, any actions for breach of
contract.  The exercise or attempted exercise by eitherparty of any such rights
or remedies shall not preclude the  simultaneous orlater exercise by such party
of any or all other  such  rights or  remedies available  at law,  in equity or
otherwise.  No course of dealing by either  party, or any  delay,  omission  or
failure of any party in  exercising  or enforcing any rights or remedies  under
this  Agreement  shall  operate as a waiver of suchright or remedy or any other
rights or remedies of such party. The parties agreethat each party, in addition
to all other remedies such party may have hereunder,at law or otherwise,  shall
have the right to enforce such party's  rights underthis Agreement by an action
or actions for specific  performance,  injunction orother appropriate equitable
remedies. In furtherance and not in limitation of theforegoing,  ImClone agrees
that in the event of its  breach of the  provisions of  Section 8 hereof,  High
River shall be  entitled,  in addition to all other remedies to which it may be
entitled,  to temporary or permanent  injunctive ormandatory relief or specific
performance without the necessity of proving damages.

                  j.  Binding Effect.  This Agreement and the rights and
interests granted herein shall be binding upon, and shall inure



<PAGE>



to the  benefit  of, the parties  and their  respective successors  (whether by
merger or otherwise) and permitted assigns.




<PAGE>


                  IN WITNESS  WHEREOF,  High River and ImClone have caused this
Agreement to be executed as of the date first above written by their respective
officers thereunto duly authorized.

                                            IMCLONE SYSTEMS INCORPORATED


                                            By:      _______________________
                                            Name:
                                            Title:

                                            HIGH RIVER LIMITED PARTNERSHIP
                                      By:      RIVERDALE INVESTORS CORP., INC.,
                                                        General Partner


                                            By:      _________________________
                                            Name:
                                            Title:


(signature page to Option from ImClone to High River for up to
300,000 shares of ImClone Common Stock)



<PAGE>





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