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                                                                    Exhibit 99.3

                          IMCLONE SYSTEMS INCORPORATED

               1998 NON-QUALIFIED STOCK OPTION PLAN, AS AMENDED(1)

                                   Article 1
                                 PURPOSE OF PLAN

         Section 1.01. General Purpose. The purpose of this Non-Qualified Stock
Option Plan (the "PLAN") is to promote the interests of ImClone Systems
Incorporated (the "COMPANY") by affording consultants, advisors, and non-officer
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
persons increased personal interest in its continued success.

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

                                   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 10,000,000 shares.

         Section 2.02. Restoration Of Unpurchased Shares. Any shares subject to
an option granted hereunder that, for any reason, expires or is terminated
unexercised as to such shares may again be subject to an option to be granted
hereunder.

                                   Article 3
                     ADMINISTRATION; COMMITTEES; AMENDMENTS

         Section 3.01. Administration. The Plan shall be administered by any of
the Compensation and Stock Option Committee (the "COMMITTEE") or the Board of
Directors of the Company (the "BOARD"). The Committee shall be comprised of not
less than two persons who shall be appointed by the Board from among the members
of the Board.

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(1)   Amended by the Board of Directors on July 7, 1998, December 16, 1999,
      September 18, 2000 , March 15, 2001 and November 15, 2001.
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         Section 3.02. Duration; Removal; Etc. The members of the Committee
shall serve at the pleasure of the Board, which shall have the power at all
times to remove members from the Committee or to add members thereto. Vacancies
in the Committee, however caused, shall be filled by action of the Board.

         Section 3.03. Meetings; Actions Of Committee. The Committee may select
one of its members as its Chairman and shall hold meetings at such times and
places as it may determine. All decisions or determinations of the Committee 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 this had been made at a meeting duly called and held. The
Committee 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
the Committee or the Board of the provisions of the Plan or of the options
granted hereunder shall be final, unless in the case of the Committee otherwise
determined by the Board. No member of the Board or of the Committee shall be
liable for an 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.

                                   Article 4
            PARTICIPANTS; PARTICIPATION GUIDELINES; DURATION OF PLAN

         Section 4.01. Eligibility And Participation. Options shall be granted
only to persons ("PARTICIPANTS") who at the time of granting are consultants,
advisors, directors or employees of the Company. The Committee or the Board
shall determine the consultants, advisors, directors and 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. Persons who are disabled within the meaning of the
Code shall not be eligible for the grant of options.

         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, either the Committee or the Board shall consult with officers and
directors of the Company, and shall take into account the duties of the
respective persons, their present and potential contributions to the success of
the Company, and such other factors of the Committee or the Board shall deem
relevant.

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         Section 4.03. Duration Of Plan. All options under the Plan shall be
granted within ten years from the date the Plan is approved by the Committee and
the Board.

                                   Article 5
                         TERMS AND CONDITIONS OF OPTIONS

         Section 5.01. Individual Stock Option Agreements or Notices. 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 Committee 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 the Committee 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 said term as the
Committee 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. 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. The Committee 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 Committee
or the Board, which shall have the 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.

         Section 5.04. Method Of Exercising Option; Full Payment. Subject to the
terms of Section 6.01 and Section 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, a key consultant, advisor or a non-officer employee of the
Company or a subsidiary. 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

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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
payment of the full purchase price of such shares, which payment shall be by
wire transfer, certified or bank check or in stock of the Company that has been
owned by the Participant for at least six months, or as agreed to by the Board,
other consideration; and 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 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. Either the Committee or the Board may amend an
already outstanding Stock Option Agreement to add a provision permitted by
clause (b) of this Section 5.4, and no such amendment, by itself, shall be
deemed to constitute the grant of a new option for purposes of this Plan.

         Section 5.05. Rights As A Share Holder. 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 a stock certificate 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 each of the Committee 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; 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) the right to
exercise any unvested option or unvested portion of any option granted under the
Plan shall terminate on

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the date of termination of the relationship between the Participant and the
Company and (b) 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 (i) the thirtieth day
following such termination of employment or service or (ii) 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 after its expiration
in accordance with the foregoing provisions, 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 he is a
consultant, advisor or non-officer employee of the Company or a subsidiary, any
options theretofore granted to him shall be exercisable only within the next 12
months immediately succeeding such death or disability and then only (a) in the
case of death, by the person or persons to whom the Participants 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 or disability.

         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 or
to a member of the immediate family of the Participant, within the meaning of
Rule 16a-1(e) of the Securities Exchange Act of 1934, as amended, a trust for
such family members, a partnership whose only partners are such family members
or a charitable institution within the meaning of Section 501(c)(3) of the Code
(each an "AUTHORIZED TRANSFEREE"). During the Participant's lifetime, options
shall be exercised only by such Participant, such Participant's guardian or
legal representative, or such Participant's Authorized Transferee.

                                   Article 7
                               CAPITAL ADJUSTMENTS

         Section 7.01. Capital. 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 either the

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Committee 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. Any
determination made by either the Committee or the Board under this Article VII
shall be final, binding and conclusive upon each Participant.

                                   Article 8
                                CHANGE IN CONTROL

         Section 8.01. Change In Control. Upon the occurrence of a Change in
Control, each outstanding option under the Plan shall become fully (100%) vested
and exercisable.

For purposes of this Plan, a "CHANGE IN CONTROL" of the Company means the
occurrence of one of the following events:

                  (i) individuals who, on the effective date of the Plan (the
         "EFFECTIVE DATE"), constitute the Board (the "INCUMBENT DIRECTORS")
         cease for any reason to constitute at least a majority of the Board,
         provided that any person becoming a director subsequent to the
         Effective Date whose election or nomination for election was approved
         by a vote of at least two-thirds of the Incumbent Directors then on the
         Board (either by a specific vote or by approval of the proxy statement
         of the Company in which such person is named as a nominee for director,
         without objection to such nomination) shall be an Incumbent Director;
         provided, however, that no individual initially elected or nominated as
         a director of the Company as a result of an actual or threatened
         election contest with respect to directors or as a result of any other
         actual or threatened solicitation of proxies by or on behalf of any
         person other than the Board shall be an Incumbent Director;

                  (ii) any "person" (as such term is defined in Section 3(a)(9)
         of the Securities Exchange Act of 1934 (the "EXCHANGE ACT") and as used
         in Sections 13(d)(3) and 14(d)(2) of the Exchange Act) is or becomes,
         after the Effective Date, a "beneficial owner" (as defined in Rule
         13d-3 under the Exchange Act), directly or indirectly, of securities of
         the Company representing 35% or more of the combined voting power of
         the Company's then outstanding securities eligible to vote for the
         election of the Board (the "COMPANY VOTING SECURITIES"); provided,
         however, that an event described in this paragraph (ii) shall not be
         deemed to be a Change in Control if any of following becomes such a
         beneficial owner: (A) the Company or any majority-owned subsidiary
         (provided, that this exclusion applies solely to the ownership levels
         of the Company or the majority-owned subsidiary), (B) any
         tax-qualified, broad-based employee benefit plan sponsored or
         maintained by the Company or any majority-

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         owned subsidiary, (C) any underwriter temporarily holding securities
         pursuant to an offering of such securities or (D) any person pursuant
         to a Non-Qualifying Transaction (as defined in paragraph (iii)).

                  (iii) the consummation of a merger, consolidation, statutory
         share exchange or similar form of corporate transaction involving the
         Company or any of its Subsidiaries that requires the approval of the
         Company's stockholders, whether for such transaction or the issuance of
         securities in the transaction (a "BUSINESS COMBINATION"), unless
         immediately following such Business Combination: (A) 60% or more of the
         total voting power of (x) the corporation resulting from such Business
         Combination (the "SURVIVING CORPORATION"), or (y) if applicable, the
         ultimate parent corporation that directly or indirectly has beneficial
         ownership of 100% of the voting securities eligible to elect directors
         of the Surviving Corporation (the "PARENT CORPORATION"), is represented
         by Company Voting Securities that were outstanding immediately prior to
         such Business Combination (or, if applicable, is represented by shares
         into which such Company Voting Securities were converted pursuant to
         such Business Combination), and such voting power among the holders
         thereof is in substantially the same proportion as the voting power of
         such Company Voting Securities among the holders thereof immediately
         prior to the Business Combination, (B) no person (other than any
         employee benefit plan (or related trust) sponsored or maintained by the
         Surviving Corporation or the Parent Corporation), is or becomes the
         beneficial owner, directly or indirectly, of 35% or more of the total
         voting power of the outstanding voting securities eligible to elect
         directors of the Parent Corporation (or, if there is no Parent
         Corporation, the Surviving Corporation) and (C) at least a majority of
         the members of the board of directors of the Parent Corporation (or if
         there is no Parent Corporation, the Surviving Corporation) following
         the consummation of the Business Combination were Incumbent Directors
         at the time of the Board's approval of the execution of the initial
         agreement providing for such Business Combination (any Business
         Combination which satisfies all of the criteria specified in (A), (B)
         and (C) above shall be deemed to be a "NON-QUALIFYING TRANSACTION"); or

                  (iv) stockholder approval of a liquidation or dissolution of
         the Company, unless the voting common equity interests of an ongoing
         entity (other than a liquidating trust) are beneficially owned,
         directly or indirectly, by the Company's shareholders in substantially
         the same proportions as such shareholders owned the Company's
         outstanding voting common equity interests immediately prior to such
         liquidation and such ongoing entity assumes all existing obligations of
         the Company under this Plan.

         Notwithstanding the foregoing, a Change in Control of the Company shall
not be deemed to occur solely because any person acquires beneficial ownership

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of more than 35% of the Company Voting Securities as a result of the acquisition
of Company Voting Securities by the Company which reduces the number of Company
Voting Securities outstanding; provided, that, if after such acquisition by the
Company such person becomes the beneficial owner of Company Voting Securities
that increases the percentage of outstanding Company Voting Securities
beneficially owned by such person, a Change in Control of the Company shall then
occur.

                                   Article 9
                             LEGAL REQUIREMENTS, ETC

         Section 9.01. 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 9.02. 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 immediately be 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 sale, 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 9.03. Private Offering. The options to be granted under the
Plan are available only to a limited number of present and future consultants,
advisors and non-officer employees of the Company 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 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

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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.

                                   Article 10
                                     GENERAL

         Section 10.01. Application Of Funds. The proceeds received by the
Company from the sale of shares of Common Stock pursuant to the exercise of
options therefore shall be used for general corporate purposes.

         Section 10.02. Right Of The Company To Terminate Relationship. Nothing
contained in the Plan or in a Stock Option Agreement shall confer upon any
Participant any right to be continued as a consultant, advisor or non-officer
employee of the Company, or interfere in any way with the right of the Company
to terminate such relationship for any reason whatsoever, with or without cause,
at any time.

         Section 10.03. No Obligation To Exercise. The granting of an option
hereunder shall impose no obligation upon the Participant to exercise such
option.

         Section 10.04. Effectiveness Of Plan. The Plan shall become effective
upon its adoption by the Committee and ratification of the Board. Options may be
granted under the Plan prior to the ratification of the Plan by the Board, but
no such option may be exercised prior to such approval.

         Section 10.05. 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.

         Section 10.06. Tax Requirements. The exercise or surrender of any
option under this Plan shall constitute a Participant's full and complete
consent to whatever action the Committee or the Board elect to satisfy the
Federal and state withholding requirements, if any, which the Committee in its
discretion deems applicable to such exercise.

         Section 10.07. Interpretations And Adjustments. To the extent permitted
by Law, an interpretation of the Plan and a decision on any matter within either
the Committee or the 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 10.08. Information. The Company shall, upon request or as may
be specifically required hereunder, furnish or cause to be furnished, all of the

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information or documentation which is necessary or required by either the
Committee or the Board to perform its duties and functions under the Plan.

         Section 10.09. 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 10.10. 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) "DISABLED". The term "disabled" shall have the definition set forth
in Section 22(a) (3) of the Code.

                                   Article 11
                                DIRECTORS' GRANTS

         Section 11.01. Directors' Grants. To the extent any Participating
Director (as such term is defined under the Company's 1996 Non-Qualified Stock
Option Plan, As Amended (the "1996 NON-QUALIFIED PLAN")) becomes eligible for an
option grant under the 1996 Non-Qualified Plan pursuant to Section 7.01 of such
plan, but the Committees (as defined thereunder) or Board do not have additional
capacity under the 1996 Non-Qualified Plan to grant such option as a result of
having reached the maximum number of authorized shares set forth in Section 2.01
of the 1996 Non-Qualified Plan (subject to adjustment pursuant to Section 8.01
of such plan), or if such grant would cause the number of shares issued or sold
pursuant to options under the 1996 Non-Qualified Plan to exceed the maximum
number of authorized shares set forth in Section 2.01 of the 1996 Non-Qualified
Plan (subject to adjustment pursuant to Section 8.01 of such plan), the
Committee or Board shall at such time grant options to such Participating
Director under this Plan.


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