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                                                                    EXHIBIT 10.3

                            OSI PHARMACEUTICALS, INC.
                    AMENDED AND RESTATED STOCK INCENTIVE PLAN
                           RESTRICTED STOCK AGREEMENT


        THIS RESTRICTED STOCK AGREEMENT (the "Agreement") is made this 1st day
of June, 2005 by and between OSI PHARMACEUTICALS, INC., a Delaware corporation
(the "Company"), and Michael Atieh (the "Employee").

        NOW, THEREFORE, the parties hereto mutually agree to the following terms
and conditions of this Agreement:

               1. ISSUANCE OF STOCK. Pursuant to the terms of the OSI
Pharmaceutical, Inc. Amended and Restated Stock Incentive Plan (the "Plan"), the
Company shall issue to the Employee 15,000 shares of Common Stock, subject to
the terms, conditions and restrictions of this Agreement and the Plan (the
"Restricted Stock"). The Company may withhold the actual delivery of a stock
certificate evidencing the Restricted Stock awarded hereunder until such shares
of Restricted Stock have become vested and transferable under the terms hereof
or may issue in the name of the Employee a certificate evidencing such shares of
Restricted Stock, which certificate shall bear a legend reflecting the
restrictions imposed under this Agreement and such other legends the Company
deems appropriate to comply with any applicable securities law.

               2. VESTING AND FORFEITURE. Shares of Restricted Stock issued
under this Agreement shall vest in five equal tranches of 3,000 shares on each
anniversary of the date hereof, commencing June 1, 2006 and terminating June 1,
2010; provided, however, that the Employee continues to be employed by the
Company or an affiliate thereof as of such date. In the event the Employee's
employment terminates from the Company and all affiliates thereof on or prior to
June 1, 2010 for any reason, the shares of Restricted Stock issued hereunder
which have not vested as of such termination date shall be forfeited as of the
date of such termination of employment, and the Employee shall have no further
rights with respect to such forfeited shares of Restricted Stock.
Notwithstanding the foregoing, all of the shares of Restricted Stock shall vest
upon a Change of Control (as such term is defined in the Amended and Restated
Employment Agreement dated May 31, 2005 between the Company and the Employee).

               3. RESTRICTION ON TRANSFERABILITY. Shares of Restricted Stock
issued hereunder shall not be sold, assigned, transferred, exchanged, pledged or
otherwise encumbered or disposed of in any manner by the Employee prior to the
date such shares become vested under Section 2 of this Agreement.

               4. VOTING, DIVIDEND AND TENDER OFFER RIGHTS. Unless shares of
Restricted Stock have been forfeited hereunder, the Employee shall have all
voting, dividend and tender offer rights with respect to shares of Restricted
Stock issued under this Agreement, whether or not such shares are vested or
unvested.
               5. SECURITIES LAWS. The Company shall not be obligated to issue
or deliver any shares of Restricted Stock under this Agreement in any manner in
contravention of the Securities Act of 1933, as amended, any other federal or
state securities law or the rules of any
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exchange or market system upon which the Common Stock is traded. The Board of
Directors of the Company or the Committee (as designated under the Plan) may, at
any time, require, as a condition to the issuance or delivery of shares of
Common Stock hereunder, the representation or agreement of the Employee to the
effect that the shares issuable hereunder are acquired by the Employee for
investment purposes and not with a view to the resale or distribution thereof,
and may require such other representations and documents as may be required to
comply with applicable securities laws or the rules of any applicable exchange
or market system.

               6. WITHHOLDING OF APPLICABLE TAXES. The Employee shall pay, or
make provision satisfactory to the Company for the payment of, any taxes the
Company is obligated to collect with respect to the issuance or vesting of
Restricted Stock under this Agreement, including but not limited to, any
applicable, federal, state, or local withholding or employment taxes. If the
Employee shall fail to pay, or make provision for the payment of, such taxes,
the Company shall have the right to withhold such amount from any compensation
or other amounts the Company owes the Employee.

               7. SUBJECT TO TERMS OF PLAN. Shares of Restricted Stock issued
hereunder are subject to the terms and provisions of the Plan. All terms used
herein which are defined in the Plan and not otherwise defined herein shall have
the same meanings as in the Plan. To the extent that the provisions hereof
conflict with those of the Plan, the provisions of the Plan shall control. All
decisions or interpretations made by the Committee regarding any issue or
question arising under this Agreement or the Plan shall be final, binding and
conclusive on the Company and the Employee.

               8. NO RIGHT TO CONTINUED EMPLOYMENT. Nothing contained herein or
in the Plan shall confer to the Employee any right to continue in the employment
of the Company or any affiliate thereof, or interfere in any way with the right
of the Company or any affiliate thereof, to terminate the employment,
responsibilities or duties of the Employee at any time for any reason
whatsoever.

               9. BINDING EFFECT. This agreement shall be binding upon and inure
to the benefit of the parties hereto, including the successors and assigns of
the Company.

      IN WITNESS WHEREOF, the parties hereto execute this Agreement as of the
day and year first above written.

                                            OSI PHARMACEUTICALS, INC.

                                            /s/ Colin Goddard
                                            -----------------------------
                                            Name: Colin Goddard
                                            Title: Chief Executive Officer


                                            EMPLOYEE

                                            /s/ Michael Atieh
                                            -----------------------------
                                            Michael Atieh


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