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                                                                   EXHIBIT 10.23

                    1991 STOCK PLAN OF INCYTE GENOMICS, INC.


                    RESTRICTED STOCK UNIT AGREEMENT

Payment for Units        No payment is required for the units you receive.
                         However, upon settlement of the units, you shall be
                         required to pay in cash the par value of any shares of
                         Common Stock you receive.

Vesting                  The units vest in installments, as shown in the Notice
                         of Restricted Stock Unit Award. In addition, the units
                         may vest upon such earlier dates as may be specified in
                         any written employment or similar agreement between you
                         and the Company.

                         No additional units vest after your service as an
                         employee, director, consultant or advisor of the
                         Company or a subsidiary of the Company has terminated
                         for any reason.

Forfeiture               If your service as an employee, director, consultant or
                         advisor of the Company or a subsidiary of the Company
                         terminates for any reason, then your units will be
                         forfeited to the extent that they have not vested
                         before the termination date and do not vest as a result
                         of the termination. This means that the units will
                         immediately be cancelled. You receive no payment for
                         units that are forfeited.

                         The Company can provide written notice to you at any
                         time terminating your service with the Company, which
                         notice shall determine when your service terminates for
                         purpose of forfeiture.

                         In addition, the units may be forfeited upon such
                         earlier dates as may be specified in any written
                         employment or similar agreement between you and the
                         Company.

Leaves of Absence        For purposes of this award, your service does not
                         terminate when you go on a military leave, a sick leave
                         or another bona fide leave of absence, if the leave was
                         approved by the Company in writing and if continued
                         crediting of service is required by the terms of the
                         leave or by applicable law. But your service terminates
                         when the approved leave ends, unless you immediately
                         return to active work.

Nature of Units          Your units are mere bookkeeping entries. They represent
                         only the Company's unfunded and unsecured promise to
                         issue shares of Common Stock (or distribute cash) on a
                         future date. As a holder of units, you have no rights
                         other than the rights of a general creditor of


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                         the Company.


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No Voting Rights or      Your units carry neither voting rights nor rights to
Dividends                dividends. You, or your estate or heirs, have no rights
                         as a stockholder of the Company unless and until your
                         units are settled by issuing shares of the Company's
                         Common Stock. No adjustments will be made for dividends
                         or other rights if the applicable record date occurs
                         before your stock certificate is issued, except as
                         described in the Plan.

Units Nontransferable    You may not sell, transfer, assign, pledge or otherwise
                         dispose of any units. For instance, you may not use
                         your units as security for a loan.

Settlement of Units      Each of your units will be settled when it vests,
                         unless you elect a later settlement date(s), for some
                         or all of your units, which may not be beyond the
                         earlier of (a) 30 days after the termination of your
                         service, or (b) the ninth anniversary of your Vesting
                         Commencement Date (the "Latest Settlement Date"). Such
                         an election must be in writing, must be received by the
                         Company at its headquarters at least 6 months before
                         the unit vests and must become irrevocable on the date
                         that is 6 months before the unit vests. You may select
                         as the settlement date(s) either one or more fixed
                         date(s) (i.e., you may elect to have your units settled
                         in a lump sum or in installments), or the date that is
                         30 days after the termination of your employment (but
                         if not settled earlier, your units will automatically
                         be settled on the Latest Settlement Date).

                         At the time of settlement, you will receive one share
                         of the Company's Common Stock for each vested unit. But
                         the Company, at its sole discretion, may substitute an
                         equivalent amount of cash, at the then fair market
                         value of the stock, if the distribution of stock is not
                         reasonably practicable due to the requirements of
                         applicable law. The amount of cash will be determined
                         on the basis of the market value of the Company's
                         Common Stock at the time of settlement.

                         Notwithstanding the foregoing, if a settlement date
                         (including the Latest Settlement Date) occurs on a date
                         that is not during a "window period," then, unless the
                         Company determines otherwise, the settlement date
                         automatically shall be deferred to the first trading
                         day of the first "window period" beginning after such
                         date. In addition, if a settlement date (including the
                         Latest Settlement Date) occurs at a time when you are
                         considered by the Company to be one of its "covered
                         employees" within the meaning of Section 162(m) of the
                         Internal Revenue Code, then, unless the Company
                         determines otherwise, delivery of the shares of Common
                         Stock (or cash) automatically shall be deferred until
                         the first trading day of the first "window period"
                         after you have ceased to be a covered employee.




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                         A "window period" means a period designated by the
                         Company during which an employee of the Company is
                         permitted to purchase or sell shares of Common Stock.

Withholding Taxes        No stock certificates or cash will be distributed to
                         you unless you have made acceptable arrangements to pay
                         any withholding taxes that may be due as a result of
                         the settlement of this award. These arrangements may
                         include withholding shares of the Company's stock that
                         otherwise would be distributed to you when the units
                         are settled. These arrangements may also include
                         surrendering shares of the Company's stock that you
                         already own. The fair market value of these shares,
                         determined as of the date when taxes otherwise would
                         have been withheld in cash, will be applied to the
                         withholding taxes.

Restrictions on Resale   By signing this Agreement, you agree not to sell any
                         shares of the Company's Common Stock issued upon
                         settlement of the units at a time when applicable laws
                         or Company policies prohibit a sale. This restriction
                         will apply as long as you are an employee, director,
                         consultant or advisor of the Company or a subsidiary of
                         the Company.

No Retention Rights      Your award or this Agreement do not give you the right
                         to be retained by the Company or a subsidiary of the
                         Company in any capacity. The Company and its
                         subsidiaries reserve the right to terminate your
                         service at any time, with or without cause.

Adjustments              In the event of a stock split, a stock dividend or a
                         similar change in the Company's Common Stock, the
                         number of your units will be adjusted accordingly, as
                         the Company may determine pursuant to the provisions of
                         the Plan otherwise applicable to stock options.

                         In the event that the Company is a party to a merger or
                         other reorganization, your units will be subject to the
                         agreement of merger or reorganization. That agreement
                         may provide, without limitation, (i) for the assumption
                         of units by the surviving corporation or its parent,
                         (ii) for the continuation of units by the Company, if
                         it is a surviving corporation, or (iii) for the
                         settlement of the units in cash.

                         Any issue by the Company of shares of stock of any
                         class, or securities convertible into shares of stock
                         of any class, shall not affect, and no adjustment by
                         reason thereof shall by made with respect to, the
                         number of your units. The grant of your units shall not
                         affect in any way the right or power of the Company to
                         make adjustments, reclassifications, reorganizations or
                         changes of its capital or business structure, to merge
                         or consolidate or to dissolve, liquidate, sell or
                         transfer all or any part of its business or assets.


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Beneficiary Designation  You may dispose of your units in a written beneficiary
                         designation. A beneficiary designation must be filed
                         with the Company on the proper form. It will be
                         recognized only if it has been received at the
                         Company's headquarters before your death. If you file
                         no beneficiary designation or if none of your
                         designated beneficiaries survives you, then your estate
                         will receive any vested units that you hold at the time
                         of your death.


Applicable Law           This Agreement will be interpreted and enforced under
                         the laws of the State of California (without regard to
                         its choice-of-law provisions).

The Plan and Other       The text of the Plan is incorporated in this Agreement
Agreements               by reference.

                         This Agreement and the Plan constitute the entire
                         understanding between you and the Company regarding
                         this award. Any prior agreements, commitments or
                         negotiations concerning this award are superseded. This
                         Agreement may be amended only by another written
                         agreement, signed by both parties.




                  BY SIGNING THE COVER SHEET OF THIS AGREEMENT,

                  YOU AGREE TO ALL OF THE TERMS AND CONDITIONS

                        DESCRIBED ABOVE AND IN THIS PLAN.




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