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                                                                   EXHIBIT 99.8

                          IMCLONE SYSTEMS INCORPORATED

                 1996 INCENTIVE STOCK OPTION PLAN, AS AMENDED(1)

                                   ARTICLE 1
                                PURPOSE OF PLAN

      Section 1.01. General Purpose. The purpose of this Incentive Stock Option
Plan (the "PLAN") is to promote the interests of ImClone Systems Incorporated,
and any subsidiaries of such company, as from time to time may be formed or
acquired (collectively, the "COMPANY"), by affording key executives and
employees an opportunity to acquire a proprietary interest in the Company
pursuant to stock options issued by the Company, and thus to create in such
employees increased personal interest in its continued success.

      Section 1.02. Statutory Stock Option.  Options granted under the Plan are
intended to be "incentive stock options" to which Section 422 of the Internal
Revenue Code of 1986, as amended (the "CODE"), applies.

                                   ARTICLE 2
                             SHARES SUBJECT TO PLAN

      Section 2.01. Description of Shares. Subject to Article VII hereof, the
stock to which the Plan applies is shares of the Company's common stock, $.001
par value ("COMMON STOCK"), either authorized but unissued or Treasury shares.
The number of shares of Common Stock to be issued or sold pursuant to options
granted hereunder shall not exceed 5,500,000 shares; provided, that such number
shall be reduced by the number of shares which have been sold under, or may be
sold pursuant to options granted from time to time under, the Company's 1996
Non-Qualified Stock Option Plan (the "Non-Qualified Plan"), to the same extent
as if such sales had been made or options had been granted pursuant to this
Plan.

      Section 2.02. Restoration of Unpurchased Shares. Any shares subject to an
option granted hereunder or under the Non-Qualified Plan that, for any reason,
expires or is terminated unexercised as to such shares may again be subject to
an option to be granted hereunder.

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      (1) This plan was adopted by the board on February 25, 1996 and approved
by the stockholders on June 3, 1996; it was amended by the Board on April 3,
1997 and such amendments were ratified by the stockholders on June 3, 1997; it
was amended by the Board on March 29, 1999 subject to shareholder approval and
such amendments were ratified by the stockholders on May 24, 1999; it was
amended by the Board on December 16, 1999; it was amended by the Board on April
14, 2000 and such amendments were ratified by the stockholders on May 31, 2000.

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                                   ARTICLE 3
                     ADMINISTRATION; COMMITTEES; AMENDMENTS

      Section 3.01. Administration. The Plan shall be administered by any of
the Compensation Committee, the Stock Option Committee (which is a subcommittee
of the Compensation Committee) (collectively, the "COMMITTEES") or the
Company's Board of Directors (the "BOARD"). The Committees shall be comprised
of not less than two persons who shall be appointed by the Board from among the
members of the Board. Members of the Committees shall not be eligible to become
participants under the Plan while they are members of the Committees or for a
period of three months thereafter.

      Section 3.02. Duration; Removal; Etc. The members of the Committees shall
serve at the pleasure of the Board, which shall have the power at all times to
remove members from the Committees or to add members thereto. Vacancies in the
Committees, however caused, shall be filled by action of the Board.

      Section 3.03. Meetings; Actions of Committees. Each of the Committees and
the Board may select one of its members as its Chairman and shall hold its
meetings at such times and places as it may determine. All decisions or
determinations of each of the Committees and the Board shall be made by the
majority vote or decision of all of its members, whether present at a meeting
or not; provided, however, that any decision or determination reduced to
writing and signed by all of the members shall be as fully effective as if it
had been made at a meeting duly called and held. Each of the Committees and the
Board may make such rules and regulations for the conduct of its business not
inconsistent herewith, as it may deem advisable.

      Section 3.04. Interpretation. The interpretation and construction by any
of the Committees or the Board of the provisions of the Plan or of the options
granted hereunder shall be final, unless in the case of the Committees
otherwise determined by the Board. No member of the Board or of the Committees
shall be liable for any action taken or determination made in good faith.

      Section 3.05. Amendments or Discontinuation. The Board may make such
amendments, changes, and additions to the Plan, or may discontinue and
terminate the Plan, as it may deem advisable from time to time; provided,
however, that no action shall affect or impair any options theretofore granted
under the Plan, and provided, further, however, that the affirmative vote of
the owners of a majority of the outstanding shares of Common Stock present at a
meeting in person or by proxy and entitled to vote at the meeting shall be
necessary to effect any amendment to the Plan which would (a) increase the
number of shares of Common Stock subject to options granted under the Plan, or
(b) authorize the granting of options at a price below the minimum price
established by Section 5.3 hereof.

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                                   ARTICLE 4
                 PARTICIPANTS; MAXIMUM GRANT; DURATION OF PLAN

      Section 4.01. Eligibility and Participation. Options shall be granted
only to persons ("PARTICIPANTS") who at the time of granting are key executives
or key employees of the Company. Subject to the provisions of Section 4.3
hereof, the Committees or the Board shall determine the key executives and key
employees to be granted options hereunder, the number of shares of Common Stock
subject to such options, the exercise prices of options, the terms thereof and
any other provisions not inconsistent with the Plan.

      Section 4.02. Guidelines for Participation. In selecting Participants and
determining the numbers of shares of Common Stock for which options are to be
granted the Committees or the Board shall consult with officers and directors
of the Company, and shall take into account the duties of the respective
employees, their present and potential contributions to the success of the
Company, and such other factors as any of the Committees or the Board shall
deem relevant.

      Section 4.03. Maximum Grant. Notwithstanding anything to the contrary in
the Plan, options granted to a Participant in any calendar year (under all
plans, including the Plan, providing for the grant of incentive stock options
of the Company and its parent and subsidiaries) in excess of the limitations of
Section 422(d) of the Code shall not be considered Incentive Stock Options
granted under this Plan and shall be deemed to be options granted under the
Non-Qualified Plan.

      Section 4.04. Duration of Plan. All options under the Plan shall be
granted within ten years from the date the Plan is adopted, or the date the
Plan is approved by the shareholders of the Company, whichever is earlier.

                                   ARTICLE 5
                        TERMS AND CONDITIONS OF OPTIONS

      Section 5.01. Individual Stock Option Agreements. All stock options
granted pursuant to the Plan shall be evidenced by stock option agreements or
notices ("STOCK OPTION AGREEMENTS"), which need not be identical, in such form
as any of the Committees or the Board shall from time to time approve, subject
to the terms of the Plan which may, but need not, be executed or acknowledged
by a Participant.

      Section 5.02. Number of Shares. Each Stock Option Agreement shall state
the total number of shares of Common Stock with respect to which the option is
granted, the terms and conditions of the option, and the exercise price or
prices thereof, it being understood that any of the Committees or the Board
shall have authority to prescribe in any Stock Option Agreement that the option
evidenced thereby may be exercisable in full or in part, as to any number of
shares subject thereto, at any time or from time to time during the term of the
option, or in such installments at such times during said term as

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any of the Committees or the Board may determine; provided that no option
granted pursuant to the Plan shall be exercisable after the expiration of ten
years from the date such option is granted. A previously granted incentive
stock option shall be treated as outstanding until it is exercised in full or
expires by reason of the lapse of time. Except as otherwise provided in any
Stock Option Agreement, an option may be exercised at any time or from time to
time during the term of the option as to any or all full (but no fractional)
shares which have become purchasable under such option. Any of the Committees
or the Board shall have the right to accelerate, in whole or in part, from time
to time, conditionally or unconditionally, the right to exercise any option
granted hereunder.

      Section 5.03. Option Price. The price at which the shares of Common Stock
subject to each option granted under this Plan may be purchased (the "OPTION
PRICE" or "EXERCISE PRICE") shall be determined by any of the Committees or the
Board, which shall have authority at the time the option is granted to
prescribe in any Stock Option Agreement that the price per share, with the
passage of pre-determined periods of time, shall increase from the original
price to higher prices, but in no case shall the original exercise price of any
option be less than 100% of the fair market value of such shares on the date
the option is granted, as determined by any of the Committees or the Board in
accordance with applicable Treasury Regulations. Notwithstanding anything
contained to the contrary herein, no option shall be granted to any employee
who, at the time the option is granted, owns more than 10% of the total
combined voting power of all classes of stock of the Company or of its parent
or subsidiary unless, at the time option is granted, the exercise price of the
option is at least 110% of the fair market value of the shares of Common Stock
subject to the option and such option by its terms is not exercisable after the
expiration of five years from the date such option is granted. For purposes of
determining the ownership of stock of the Company, the rules of Section 424(d)
of the Code shall be applied.

      Section 5.04. Method of Exercising Option; Full Payment. Subject to
Section 6.01 and 6.02 hereof, options granted pursuant to the Plan may be
exercised only if the Participant was, at all times during the period beginning
on the date the option was granted and ending on the date of such exercise, an
employee of the Company, a parent or subsidiary of the Company, or a
corporation or a parent or subsidiary of such corporation issuing or assuming a
stock option in respect of such option in a transaction to which Section 424(a)
of the Code applies. Options shall be exercised by written notice to the
Company, addressed to the Company at its principal place of business. Such
notice shall state the Participant's election to exercise the option and the
number of shares of Common Stock in respect of which it is being exercised, and
shall be signed by the Participant so exercising the option. Such notice shall
be accompanied by (a) payment of the full purchase price of such shares, which
payment shall be in cash, by check or in stock of the Company that has been
owned by the participant for at least six months, or notes of the Company or,
as agreed to by the Board, other consideration; and (b) such written
representations and other documents as may be desirable, in the opinion of the
Company's legal counsel, for purposes of compliance with state or Federal
securities or other laws. In the case of payment made in stock of the Company,
the stock shall be

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valued at its Fair Market Value (as hereinafter defined) on the last business
day prior to the date of exercise. The term "FAIR MARKET VALUE" for the Common
Stock on any particular date shall mean the last reported sale price of the
Common Stock on the principal market on which the Common Stock trades on such
date or, if no trades of Common Stock are made or reported on such date, then
on the next preceding date on which the Common Stock traded. The Company shall
deliver a certificate or certificates representing shares of Common Stock
purchased pursuant to such notice to the purchaser as soon as practicable after
receipt of such notice, subject to Article VIII hereof. Any of the Committees
or the Board may amend an already outstanding Stock Option Agreement to add a
provision permitted by clause (a) of this Section 5.04, and no such amendment,
by itself, shall be deemed to constitute the grant of a new option for purposes
of this Plan; provided that this sentence shall not be determinative of whether
any such amendment constitutes a new grant for purposes of qualification as an
Incentive Stock Option.

      Section 5.05. Rights as a Shareholder. No Participant shall have any
rights as a shareholder with respect to shares of Common Stock subject to an
option granted under the Plan until the date of the issuance to such
Participant of stock certificates in respect of such shares. No adjustment
shall be made for dividends or other rights for which the record date is prior
to the date such stock certificate is issued.

      Section 5.06. Other Provisions. Stock Option Agreements entered into
pursuant to the Plan may contain such other provisions (not inconsistent with
the Plan) as any of the Committees or the Board may deem necessary or
desirable, including, but not limited to, covenants on the part of the
Participant not to compete, not to sell Common Stock obtained from the exercise
of options for specified periods of time, and remedies available to the Company
in the event of the breach of any such covenant.

                                   ARTICLE 6
                   TERMINATION OF EMPLOYMENT; TRANSFERABILITY

      Section 6.01. Termination of Employment. Except as otherwise provided in
connection with the grant of any option or the termination of any Participant,
in the event a Participant's employment or service with the Company is
terminated other than by reason of death or disability, (a) with respect to
options granted prior to December 16, 1999, the right to exercise any
unexercised option or unexercised portion of any option (regardless of whether
or not vested) granted under the Plan shall terminate on the date of
termination of the relationship between the Participant and the Company and,
(b) with respect to options granted on or after December 16, 1999, (i) the
right to exercise any unvested option or unvested portion of any option granted
under the Plan shall terminate on the date of termination of the relationship
between the Participant and the Company and (ii) the right to exercise any
option or portion of any option granted under the Plan which is vested as of
the date of termination of employment or service shall terminate upon the
earlier of (A) the thirtieth day following such termination of employment or
service or (B) the date such option or portion of an option would have expired
had it not been for the termination of employment or service. The option may
not be exercised

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after its expiration in accordance with the foregoing terms, and the shares of
Common Stock subject to the unexercised portion of such option may again be
subject to new options under the Plan. Section 6.02. Death or Disability of
Participant. Except as otherwise permitted in connection with the grant of any
option or the death or disability of a Participant, in the event a Participant
dies or is disabled while in the employ of the Company or of a parent or
subsidiary of the Company, any options theretofore granted to him shall be
exercisable only within the next 12 months immediately succeeding such death or
disability and then only in the case of death (a) by the person or persons to
whom the Participant's rights under the option shall pass by will or the laws
of descent and distribution, and, in the case of disability, by such
Participant or his legal representative, and (b) if and to the extent that he
was entitled to exercise the option at the date of his death.

      Section 6.03. Transferability. Options granted to a Participant under the
Plan shall not be transferable otherwise than by will, by the laws of descent
and distribution, or (if authorized in the applicable Stock Option Agreement)
pursuant to a qualified domestic relations order ("QDRO") as defined by the
Internal Revenue Code of 1986, as amended, or Title I of the Employee
Retirement Income Security Act of 1974, as amended, or the rules thereunder.
During the Participant's lifetime, options shall be exercised only by such
Participant, such Participant's guardian or legal representative, or (if
authorized in the applicable Stock Option Agreement) such Participant's
transferee pursuant to a QDRO.

                                   ARTICLE 7
                              CAPITAL ADJUSTMENTS

      Section 7.01. Capital Adjustments. If any change is made in the shares of
Common Stock subject to the Plan or subject to any option granted under the
Plan (through merger, consolidation, reorganization, recapitalization, stock
dividend, split-up, combination of shares, exchange of shares, issuance of
rights to subscribe, or change in capital structure), appropriate adjustments
shall be made by any of the Committees or the Board as to the maximum number of
shares subject to the Plan and the number of shares and price per share subject
to outstanding options as shall be equitable to prevent dilution or enlargement
of option rights; provided, however, that any such adjustment shall comply with
the rules of Section 424(a) of the Code and provided further that in no event
shall any adjustment be made that would cause any option granted hereunder to
be considered other than an incentive stock option. Any determination made by
any of the Committees or the Board under this Article VII shall be final,
binding and conclusive upon each Participant.

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                                   ARTICLE 8
                            LEGAL REQUIREMENTS, ETC

      Section 8.01. Revenue Stamps.  The Company shall be responsible and shall
pay for any transfer, revenue, or documentary stamps with respect to shares
issued upon the exercise of options granted under the Plan.

      Section 8.02. Legal Requirements. The Company shall not be required to
issue certificates for shares upon the exercise of any option unless and until,
in the opinion of the Company's legal counsel, such issuance would not result
in a violation of any state or Federal securities or other law. Certificates
for shares, when issued, shall have, if required in the opinion of the
Company's legal counsel, the following legend, or statements of other
restrictions, endorsed thereon, and may not be immediately transferable:

      The shares of Common Stock evidenced by this certificate have been issued
      to the registered owner in reliance upon written representations that
      these shares have been purchased for investment. These shares may not be
      sold, transferred, or assigned unless, in the opinion of the Company and
      its legal counsel, such sales, transfer, or assignment will not be in
      violation of the Securities Act of 1933, as amended, applicable rules and
      regulations of the Securities and Exchange Commission and any applicable
      state Securities laws.

      Section 8.03. Private Offering. The options to be granted under the Plan
are available only to a limited number of present and future key executives and
employees of the Company and its subsidiaries who have knowledge of the
Company's financial condition, management, and affairs. Such options are not
intended to provide additional capital for the Company but are to encourage
stock ownership by the Company's key personnel. By the act of accepting an
option, in the absence of an effective registration statement under the
Securities Act of 1933, as amended, Participants shall agree that upon exercise
of such option, they will acquire the shares of Common Stock that are the
subject thereof for investment and not with any intention at such time to
resell or redistribute the same, and they shall confirm such agreement at the
time of exercise, but the neglect or failure to confirm the same in writing
shall not be a limitation of such agreement.

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                                   ARTICLE 9
                                    GENERAL

      Section 9.01. Application of Funds. The proceeds received by the Company
from the sale of shares of Common Stock pursuant to the exercise of options
therefor shall be used for general corporate purposes.

      Section 9.02. Right of the Company to Terminate Employment. Nothing
contained in the Plan or in a Stock Option Agreement shall confer upon any
Participant any right to be continued in the employ of the Company or of any
subsidiary of the Company, or interfere in any way with the right of the
Company, or such subsidiary, to terminate his employment for any reason
whatsoever, with or without cause, at any time.

      Section 9.03. No Obligation to Exercise. The granting of an option
hereunder shall impose no obligation upon the Participant to exercise such
option.

      Section 9.04. Effectiveness of Plan. The Plan shall become effective upon
its adoption by the shareholders of the Company.  Options may be granted under
the Plan prior to the approval of the Plan by the Shareholders, but no such
option may be exercised prior to such approval.

      Section 9.05. Other Benefits. Participation in the Plan shall not
preclude a Participant from eligibility in any other stock benefit plan of the
Company or any old age benefit, insurance, pension, profit sharing, retirement,
bonus or other plan which the Company has adopted, or may, at any time, adopt
for the benefit of its parents' or its subsidiaries executives and/or
employees.

      Section 9.06. Company Records. Records of the Company as to a
Participant's period of employment, termination of employment and the reason
therefor, leaves of absence, re-employment, and other matters will be
conclusive for all purposes hereunder.

      Section 9.07. Tax Requirement. The exercise or surrender of any option
under this Plan shall constitute a Participant's full and complete consent to
whatever action the Committee elects to satisfy the Federal and state
withholding requirements, if any, which the Committee in its discretion deems
applicable to such exercise.

      Section 9.08. Interpretations and Adjustments. To the extent permitted by
law, an interpretation of the Plan and a decision on any matter within any of
the Committees or Board's discretion made in good faith is binding on all
persons. A misstatement or other mistake of fact shall be corrected when it
becomes known, and the person responsible shall make such adjustment on account
thereof as he considers equitable and practicable.

      Section 9.09. Information. The Company shall, upon request or as may be
specifically required hereunder, furnish or cause to be furnished, all of the
information or

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documentation which is necessary or required by any of the Committees or the
Board to perform its duties and functions under the Plan.

      Section 9.10.  Notice of Disqualifying Disposition. If a Participant
sells or otherwise disposes of any share of Common Stock transferred to him
pursuant to the exercise of an option granted hereunder within two years from
the date of the granting of the option or within one year of the transfer of
such shares to him (i.e., a "disqualifying disposition"), the Participant,
within ten days thereafter, shall furnish to any of the Committees or the Board
at the principal offices of the Company, written notice of such sale or other
disposition.

      Section 9.11. Governing Law.  The Plan and any and all options granted
thereunder shall be governed by, and construed and enforced in accordance with,
the laws of the State of New York from time to time in effect.

      Section 9.12. Certain Definitions.

      (a)   "PARENT".  The term "parent" shall mean a "parent corporation" as
defined in Section 424(e) of the Code.

      (b)   "SUBSIDIARY".  The term "subsidiary" shall mean a "subsidiary
corporation" as defined in Section 424(f) of the Code.

      (c)   "INCENTIVE STOCK OPTION".  The term "incentive stock option" shall
mean an option described in Section 422(b) of the code.

      (d)   "DISABLED".  The term "disabled" shall have the definition set
forth in Section 22(a)(3) of the Code.