TABLE OF CONTENTS

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IMCLONE SYSTEMS INCORPORATED
TRANSITION SEVERANCE PLAN

ARTICLE I - INTRODUCTION

ImClone Systems Incorporated (the “Company”) hereby establishes the ImClone Systems Incorporated Transition Severance Plan (the “Plan”), effective as of March 1, 2006, to provide severance benefits to select employees of the Company who suffer a loss of employment under the terms and conditions set forth in the Plan. The Plan will remain in effect for a period of 18 months following its effective date (i.e., through August 31, 2007) (the “Term”), and is intended to make severance payments in lieu of, and not in addition to, payments under any and all severance plans, policies and/or practices of the Company (including the ImClone Systems Incorporated Senior Executive Severance Plan) in effect for covered employees. The Plan is not intended to supersede or replace such other severance plans, policies and/or practices following the expiration of the Term, and such other severance plans, policies and/or practices will continue to apply, if then in effect, following the expiration of the Term in accordance with their terms. The Plan is intended to fall within the definition of an “employee welfare benefit plan” under Section 3(1) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”). No employee or representative of the Company or its affiliates is authorized to modify, add to or subtract from the terms and conditions in the Plan, except in accordance with the amendment and termination procedures described herein.

ARTICLE II - DEFINITIONS AND INTERPRETATIONS

The following definitions and interpretations of important terms apply to the Plan.

1.                                        Agreement and Release . An Agreement and General Release in a form acceptable to the Plan Administrator, in its sole and absolute discretion, under which, among other things, the Eligible Employee releases and discharges the Company and related entities (as well as any third party for whom the Eligible Employee provides services on the Company’s behalf) from any and all claims and liabilities relating to the Eligible Employee’s employment with the Company and/or the termination of the Eligible Employee’s employment, including without limitation, claims under the Title VII of the Civil Rights Act of 1964, the Americans with Disabilities Act, the Family and Medical Leave Act, the Age Discrimination in Employment Act, the Sarbanes Oxley Act and, where applicable, the Older Workers Benefit Protection Act, the New Jersey Law Against Discrimination, the New Jersey Conscientious Employee Protection Act (Whistleblowing Law) and the New York State and City Human Rights Laws (and similar laws of any other state or locality).

2.                                        Board . The Board of Directors of the Company.

3.                                        Cause . Any one of the following circumstances:

(i)                                      the performance by the Eligible Employee of his or her employment duties in a manner deemed by the Company to be unsatisfactory in any way; provided that the Eligible Employee had previously received a written warning identifying the problem and

outlining a course of corrective action, has been given a reasonable opportunity to correct his or her performance, and has failed or refused to do so;

(ii)                                   the performance by the Eligible Employee of his or her employment duties in a manner deemed by the Company to be grossly incompetent or grossly negligent;

(iii)                                any other willful misconduct or gross negligence resulting, in either case, in harm to the Company or a subsidiary;

(iv)                               indictment involving a felony or misdemeanor involving moral turpitude or the commission of a criminal act by the Eligible Employee, whether or not performed in the workplace, which subjects, or if generally known, would subject, the Company to public ridicule or embarrassment;

(v)                                  failure to carry out directions of the Board or the Eligible Employee’s immediate supervisor;

(vi)                               fraud, embezzlement, theft or dishonesty against the Company or a subsidiary resulting in harm to the Company or a subsidiary;

(vii)                            material violation of Company policies, rules or procedures resulting in harm to the Company or a subsidiary;

(viii)                         violent acts, threats of violence or unauthorized possession of alcohol or controlled substances on Company property; or

(ix)                                 acts intended to result in personal gain at the expense of the Company or through the improper disclosure of proprietary information or trade secrets.

The determination of whether a discharge or other separation from employment is for Cause shall be made by the Plan Administrator, in its sole and absolute discretion, and such determination shall be conclusive and binding on the affected Eligible Employee.

4.                                        Change in Control . The occurrence of one of the following events during the Term:

(i)                                      individuals who, on 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, further, 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;

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(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 40% 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 Clause (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-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 Clause (iii) below);

(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)                               50% 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 40% or more of the total voting

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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 of more than 40% 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.

5.                                        Committee . The Compensation Committee of the Board.

6.                                        Company . ImClone Systems Incorporated, and its successors.

7.                                        Effective Date . March 1, 2006.

8.                                        Eligible Employee . Any active, regular, full-time, U.S.-based, salaried employee of the Company in a position at a level of Vice President or below who is designated by the Plan Administrator, in a written designation delivered to the Eligible Employee, as eligible to become a Participant under this Plan. Notwithstanding the preceding sentence, “Eligible Employee” does not include any employee who is a party to a formal, written employment agreement with the Company that provides for severance or other payments in the event of the individual’s termination of employment or other separation from service with the Company (regardless of the circumstances). “Eligible Employee” also does not include any individual (i) designated by the Company as an independent contractor and not as an employee at the time of any determination under the Plan, (ii) being paid by or through a third party agency, (iii) designated by the Company as a freelance worker and not as an employee at the time of any determination under the Plan, (iv) designated by the Company as a seasonal, occasional, limited duration, leased or temporary employee, during the period the individual is so paid or

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designated. Any such individual shall not be an Eligible Employee even if he or she is later retroactively reclassified as a common-law or other type of employee of the Company during all or any part of such period pursuant to applicable law or otherwise. Employees of the Company in a position at a level of Senior Vice President or above are not eligible to participate in the Plan.

9.                                        Good Reason . Any one of the following circumstances that occurs on or following a Change in Control, and within the 60-day period preceding a Termination Date:

(i)                                      a reduction in the Eligible Employee’s base salary without the Eligible Employee’s prior written consent (other than any reduction applicable to similarly situated employees of the Company generally); or

(ii)                                   an actual change in the Eligible Employee’s principal work location by more than 35 miles from its current location and more than 35 miles from the Eligible Employee’s principal place of abode as of the date of such change in job location without the Eligible Employee’s prior written consent.

10.                                  Participant . An Eligible Employee who meets the requirements for eligibility under the Plan, as set forth in Article III of the Plan. An individual shall cease being a Participant once all Plan benefits due to such individual under the Plan have been paid (or, if earlier, upon the death of the Participant) and no person shall have any further rights under this Plan with respect to such former Participant.

11.                                  Plan Administrator . The Chief Executive Officer of the Company. The Chief Executive Officer may designate a person or committee to perform day to day administrative duties for the Plan.

12.                                  Term . The period of 18 months following the Effective Date (i.e., through August 31, 2007). The Plan applies to Participants who experience a Termination of Employment during the Term.

13.                                  Termination Date . The date on which a Participant experiences a Termination of Employment with the Company.

14.                                  Termination of Employment .

(i)                                      The termination by the Company of an Eligible Employee’s employment relationship with the Company as the result of job elimination, job discontinuation, office closing, staff reduction, organizational restructuring, or unsatisfactory job performance that does not constitute Cause; or

(ii)                                   The termination by the Eligible Employee of the Eligible Employee’s employment relationship with the Company for Good Reason.

Termination of Employment does not include termination of an Eligible Employee’s employment relationship with the Company due to death or disability, or a

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discharge or separation from service with the Company under any of the following circumstances: retirement, v