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                                                                    Exhibit 10.1

                               1991 STOCK PLAN OF
                              INCYTE GENOMICS, INC.
                 (As Amended and Restated on February 15, 2001)

SECTION 1.  ESTABLISHMENT AND PURPOSE.

     The Plan was adopted on November 7, 1991, and most recently amended and
restated on February 15, 2001. The purpose of the Plan is to offer selected
employees and consultants an opportunity to acquire a proprietary interest in
the success of the Company, or to increase such interest, by purchasing Shares
of the Company's Stock. The Plan provides both for the direct award or sale of
Shares and for the grant of Options to purchase Shares. Options granted under
the Plan may include Nonstatutory Options as well as ISOs intended to qualify
under section 422 of the Code.

     The Plan is intended to comply in all respects with Rule 16b-3 (or its
successor) under the Exchange Act and shall be construed accordingly.

SECTION 2.  DEFINITIONS.

     (a) "Board of Directors" shall mean the Board of Directors of the Company,
as constituted from time to time.

     (b) "Change in Control" shall mean the occurrence of either of the
following events:

          (i) A change in the composition of the Board of Directors, as a result
     of which fewer than one-half of the incumbent directors are directors who
     either:

               (A) Had been directors of the Company 24 months prior to such
          change; or

               (B) Were elected, or nominated for election, to the Board of
          Directors with the affirmative votes of at least a majority of the
          directors who had been directors of the Company 24 months prior to
          such change and who were still in office at the time of the election
          or nomination; or

          (ii) Any "person" (as such term is used in sections 13(d) and 14(d) of
     the Exchange Act) by the acquisition or aggregation of securities is or
     becomes the beneficial owner, directly or indirectly, of securities of the
     Company representing 50 percent or more of the combined voting power of the
     Company's then outstanding securities ordinarily (and apart from rights
     accruing under special circumstances) having the right to vote at elections
     of directors (the "Base Capital Stock"); except that any change in the
     relative beneficial ownership of the Company's securities by any person
     resulting solely from a reduction in the aggregate number of outstanding
     shares of Base Capital Stock, and any decrease thereafter in such person's
     ownership of securities, shall be disregarded until such person increases
     in any manner, directly or indirectly, such person's beneficial ownership
     of any securities of the Company.

     (c) "Code" shall mean the Internal Revenue Code of 1986, as amended.



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     (d) "Committee" shall mean a committee of the Board of Directors, as
described in Section 3(a).

     (e) "Company" shall mean Incyte Genomics, Inc. (formerly Incyte
Pharmaceuticals, Inc.), a Delaware corporation.

     (f) "Employee" shall mean (i) any individual who is a common-law employee
of the Company or of a Subsidiary or (ii) an independent contractor who performs
services for the Company or a Subsidiary and who is not a member of the Board of
Directors. Service as an independent contractor shall be considered employment
for all purposes of the Plan except the second sentence of Section 4(a).

     (g) "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended.

     (h) "Exercise Price" shall mean the amount for which one Share may be
purchased upon exercise of an Option, as specified by the Committee in the
applicable Stock Option Agreement.

     (i) "Fair Market Value," with respect to a Share, shall mean the market
price of one Share of Stock, determined by the Committee as follows:

          (i) If the Stock was traded over-the-counter on the date in question
     but was not traded on The Nasdaq Stock Market, then the Fair Market Value
     shall be equal to the last-transaction price quoted for such date by the
     OTC Bulletin Board or, if not so quoted, shall be equal to the mean between
     the last reported representative bid and asked prices quoted for such date
     by the principal automated inter-dealer quotation system on which the Stock
     is quoted or, if the Stock is not quoted on any such system, by the "Pink
     Sheets" published by the National Quotation Bureau, Inc.;

          (ii) If the Stock was traded on The Nasdaq Stock Market, then the Fair
     Market Value shall be equal to the last reported sale price quoted for such
     date by The Nasdaq Stock Market;

          (iii) If the Stock was traded on a United States stock exchange on the
     date in question, then the Fair Market Value shall be equal to the closing
     price reported for such date by the applicable composite-transactions
     report; and

          (iv) If none of the foregoing provisions is applicable, then the Fair
     Market Value shall be determined by the Committee in good faith on such
     basis as it deems appropriate.

In all cases, the determination of Fair Market Value by the Committee shall be
conclusive and binding on all persons.

     (j) "ISO" shall mean an employee incentive stock option described in
section 422(b) of the Code.

     (k) "Nonstatutory Option" shall mean an employee stock option not described
in sections 422(b) or 423(b) of the Code.

     (l) "Offeree" shall mean an individual to whom the Committee has offered
the right to

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acquire Shares under the Plan (other than upon exercise of an Option).

     (m) "Option" shall mean an ISO or Nonstatutory Option granted under the
Plan and entitling the holder to purchase Shares.

     (n) "Optionee" shall mean an individual who holds an Option.

     (o) "Plan" shall mean this Amended and Restated 1991 Stock Plan of Incyte
Genomics, Inc.

     (p) "Purchase Price" shall mean the consideration for which one Share may
be acquired under the Plan (other than upon exercise of an Option), as specified
by the Committee.

     (q) "Service" shall mean service as an Employee.

     (r) "Share" shall mean one share of Stock, as adjusted in accordance with
Section 9 (if applicable).

     (s) "Stock" shall mean the Common Stock, $.001 par value, of the Company.

     (t) "Stock Option Agreement" shall mean the agreement between the Company
and an Optionee which contains the terms, conditions and restrictions pertaining
to his or her Option.

     (u) "Stock Purchase Agreement" shall mean the agreement between the Company
and an Offeree who acquires Shares under the Plan which contains the terms,
conditions and restrictions pertaining to the acquisition of such Shares.

     (v) "Subsidiary" shall mean any corporation, if the Company and/or one or
more other Subsidiaries own not less than 50 percent of the total combined
voting power of all classes of outstanding stock of such corporation. A
corporation that attains the status of a Subsidiary on a date after the adoption
of the Plan shall be considered a Subsidiary commencing as of such date.

     (w) "Total and Permanent Disability" shall mean that the Optionee is unable
to engage in any substantial gainful activity by reason of any medically
determinable physical or mental impairment which can be expected to result in
death or which has lasted, or can be expected to last, for a continuous period
of not less than one year.

SECTION 3.  ADMINISTRATION.

     (a) Committee Composition. The Plan shall be administered by the Committee.
The Committee shall consist of two or more directors of the Company who shall
satisfy the requirements of Rule 16b-3 (or its successor) under the Exchange Act
with respect to the grant of Awards to persons who are officers or directors of
the Company under Section 16 of the Exchange Act or the Board itself. The Board
may also appoint one or more separate committees of the Board, each composed of
one or more directors of the Company who need not qualify under Rule 16b-3, who
may administer the Plan with respect to Employees who are not considered
officers or directors of the Company under Section 16 of the Exchange Act, may
grant Shares and Options under the Plan to such Employees and may determine all
terms of such grants.

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     (b) Committee Procedures. The Board of Directors shall designate one of the
members of the Committee as chairman. The Committee may hold meetings at such
times and places as it shall determine. The acts of a majority of the Committee
members present at meetings at which a quorum exists, or acts reduced to or
approved in writing by all Committee members, shall be valid acts of the
Committee.

     (c) Committee Responsibilities. Subject to the provisions of the Plan, the
Committee shall have full authority and discretion to take the following
actions:

          (i) To interpret the Plan and to apply its provisions;

          (ii) To adopt, amend or rescind rules, procedures and forms relating
     to the Plan;

          (iii) To authorize any person to execute, on behalf of the Company,
     any instrument required to carry out the purposes of the Plan;

          (iv) To determine when Shares are to be awarded or offered for sale
     and when Options are to be granted under the Plan;

          (v) To select the Offerees and Optionees;

          (vi) To determine the number of Shares to be offered to each Offeree
     or to be made subject to each Option;

          (vii) To prescribe the terms and conditions of each award or sale of
     Shares, including (without limitation) the Purchase Price, and to specify
     the provisions of the Stock Purchase Agreement relating to such award or
     sale;

          (viii) To prescribe the terms and conditions of each Option, including
     (without limitation) the Exercise Price, to determine whether such Option
     is to be classified as an ISO or as a Nonstatutory Option, and to specify
     the provisions of the Stock Option Agreement relating to such Option;

          (ix) To amend any outstanding Stock Purchase Agreement or Stock Option
     Agreement, subject to applicable legal restrictions and to the consent of
     the Offeree or Optionee who entered into such agreement;

          (x) To prescribe the consideration for the grant of each Option or
     other right under the Plan and to determine the sufficiency of such
     consideration; and

          (xi) To take any other actions deemed necessary or advisable for the
     administration of the Plan.

All decisions, interpretations and other actions of the Committee shall be final
and binding on all Offerees, all Optionees, and all persons deriving their
rights from an Offeree or Optionee. No member of the Committee shall be liable
for any action that he or she has taken or has failed to take in good faith with
respect to the Plan, any Option, or any right to acquire Shares under the Plan.

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SECTION 4.  ELIGIBILITY.

     (a) General Rule. Only Employees, as defined in Section 2(f), shall be
eligible for designation as Optionees or Offerees by the Committee. In addition,
only individuals who are employed as common-law employees by the Company or a
Subsidiary shall be eligible for the grant of ISOs.

     (b) Ten-Percent Stockholders. An Employee who owns more than 10 percent of
the total combined voting power of all classes of outstanding stock of the
Company or any of its Subsidiaries shall not be eligible for the grant of an ISO
unless (i) the Exercise Price is at least 110 percent of the Fair Market Value
of a Share on the date of grant and (ii) such ISO by its terms is not
exercisable after the expiration of five years from the date of grant.

     (c) Attribution Rules. For purposes of Subsection (b) above, in determining
stock ownership, an Employee shall be deemed to own the stock owned, directly or
indirectly, by or for such Employee's brothers, sisters, spouse, ancestors and
lineal descendants. Stock owned, directly or indirectly, by or for a
corporation, partnership, estate or trust shall be deemed to be owned
proportionately by or for its stockholders, partners or beneficiaries. Stock
with respect to which such Employee holds an option shall not be counted.

     (d) Outstanding Stock. For purposes of Subsection (b) above, "outstanding
stock" shall include all stock actually issued and outstanding immediately after
the grant. "Outstanding stock" shall not include shares authorized for issuance
under outstanding options held by the Employee or by any other person.

SECTION 5.  STOCK SUBJECT TO PLAN.

     (a) Basic Limitation. Shares offered under the Plan shall be authorized but
unissued Shares or treasury Shares. The aggregate number of Shares which may be
issued under the Plan (upon exercise of Options or other rights to acquire
Shares) shall not exceed 19,900,000 Shares, subject to adjustment pursuant to
Section 9. The number of Shares that are subject to Options or other rights
outstanding at any time under the Plan shall not exceed the number of Shares
that then remain available for issuance under the Plan. The Company, during the
term of the Plan, shall at all times reserve and keep available sufficient
Shares to satisfy the requirements of the Plan.

     (b) Additional Shares. In the event that any outstanding Option or other
right for any reason expires or is canceled or otherwise terminated, the Shares
allocable to the unexercised portion of such Option or other right shall again
be available for the purposes of the Plan. In the event that Shares issued under
the Plan are reacquired by the Company pursuant to any forfeiture provision,
right of repurchase or right of first refusal, such Shares shall again be
available for the purposes of the Plan.

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SECTION 6.  TERMS AND CONDITIONS OF AWARDS OR SALES.

     (a) Stock Purchase Agreement. Each award or sale of Shares under the Plan
(other than upon exercise of an Option) shall be evidenced by a Stock Purchase
Agreement between the Offeree and the Company. Such award or sale shall be
subject to all applicable terms and conditions of the Plan and may be subject to
any other terms and conditions which are not inconsistent with the Plan and
which the Committee deems appropriate for inclusion in a Stock Purchase
Agreement. The provisions of the various Stock Purchase Agreements entered into
under the Plan need not be identical.

     (b) Duration of Offers and Nontransferability of Rights. Any right to
acquire Shares under the Plan (other than an Option) shall automatically expire
if not exercised by the Offeree within 30 days after the grant of such right was
communicated to the Offeree by the Committee. Such right shall not be
transferable and shall be exercisable only by the Offeree to whom such right was
granted.

     (c) Purchase Price. The Purchase Price of Shares to be offered under the
Plan shall not be less than the par value of such Shares. Subject to the
preceding sentence, the Purchase Price shall be determined by the Committee at
its sole discretion. The Purchase Price shall be payable in a form described in
Section 8.

     (d) Withholding Taxes. As a condition to the award, purchase, vesting or
sale of Shares, the Offeree shall make such arrangements as the Committee may
require for the satisfaction of any federal, state, local or foreign withholding
tax obligations that may arise in connection with such Shares. The Committee may
permit the Offeree to satisfy all or part of his or her tax obligations related
to such Shares by having the Company withhold a portion of any Shares that
otherwise would be issued to him or her or by surrendering any Shares that
previously were acquired by him or her. The Shares withheld or surrendered shall
be valued at their Fair Market Value on the date when taxes otherwise would be
withheld in cash. The payment of taxes by assigning Shares to the Company, if
permitted by the Committee, shall be subject to such restrictions as the
Committee may impose, including any restrictions required by rules of the
Securities and Exchange Commission.

     (e) Restrictions on Transfer of Shares. Any Shares awarded or sold under
the Plan shall be subject to such special forfeiture conditions, rights of
repurchase, rights of first refusal and other transfer restrictions as the
Committee may determine. Such restrictions shall be set forth in the applicable
Stock Purchase Agreement and shall apply in addition to any general restrictions
that may apply to all holders of Shares.

SECTION 7.  TERMS AND CONDITIONS OF OPTIONS.

     (a) Stock Option Agreement. Each grant of an Option under the Plan shall be
evidenced by a Stock Option Agreement between the Optionee and the Company. Such
Option shall be subject to all applicable terms and conditions of the Plan and
may be subject to any other terms and conditions which are not inconsistent with
the Plan and which the Committee deems appropriate for inclusion in a Stock
Option Agreement. The provisions of the various Stock Option Agreements entered
into under the Plan need not be identical.

     (b) Number of Shares. Each Stock Option Agreement shall specify the number
of Shares that are subject to the Option and shall provide for the adjustment of
such number in accordance with Section 9. The Stock Option Agreement shall also
specify whether the Option is an ISO or a

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Nonstatutory Option. Options granted to any Optionee in a single calendar year
shall in no event cover more than 800,000 Shares, subject to adjustment in
accordance with Section 9.

     (c) Exercise Price. Each Stock Option Agreement shall specify the Exercise
Price. The Exercise Price of an ISO shall not be less than 100 percent of the
Fair Market Value of a Share on the date of grant, and a higher percentage may
be required by Section 4(b). The Exercise Price of a Nonstatutory Option shall
not be less than 100 percent of the Fair Market Value of a Share on the date of
grant. Subject to the preceding two sentences, the Exercise Price under any
Option shall be determined by the Committee at its sole discretion. The Exercise
Price shall be payable in a form described in Section 8.

     (d) Withholding Taxes. As a condition to the exercise of an Option, the
Optionee shall make such arrangements as the Committee may require for the
satisfaction of any federal, state, local or foreign withholding tax obligations
that may arise in connection with such exercise. The Optionee shall also make
such arrangements as the Committee may require for the satisfaction of any
federal, state, local or foreign withholding tax obligations that may arise in
connection with the disposition of Shares acquired by exercising an Option. The
Committee may permit the Optionee to satisfy all or part of his or her tax
obligations related to the Option by having the Company withhold a portion of
any Shares that otherwise would be issued to him or her or by surrendering any
Shares that previously were acquired by him or her. Such Shares shall be valued
at their Fair Market Value on the date when taxes otherwise would be withheld in
cash. The payment of taxes by assigning Shares to the Company, if permitted by
the Committee, shall be subject to such restrictions as the Committee may
impose, including any restrictions required by rules of the Securities and
Exchange Commission.

     (e) Exercisability. Each Stock Option Agreement shall specify the date when
all or any installment of the Option is to become exercisable. A Stock Option
Agreement may provide for accelerated exercisability in the event of the
Optionee's death, Total and Permanent Disability or retirement or other events.

     (f) Effect of Change in Control. The Committee may determine, at the time
of granting an Option or thereafter, that such Option shall become exercisable
on an accelerated basis in the event that a Change in Control occurs with
respect to the Company. If the Committee finds that there is a reasonable
possibility that, within the succeeding six months, a Change in Control will
occur with respect to the Company, then the Committee may determine that all
outstanding Options shall be exercisable on an accelerated basis.

     (g) Term. The Stock Option Agreement shall specify the term of the Option.
The term shall not exceed 10 years from the date of grant, except as otherwise
provided in Section 4(b). Subject to the preceding sentence, the Committee at
its sole discretion shall determine when an Option is to expire.

     (h) Nontransferability. Except as may be provided in the applicable Stock
Option Agreement with respect to a Nonstatutory Option, no Option shall be
transferable by the Optionee other than by will, by beneficiary designation
delivered to the Company, or by the laws of descent and distribution. An Option
may be exercised during the lifetime of the Optionee only by the Optionee or by
the Optionee's guardian or legal representative. No Option or interest therein
may be transferred, assigned, pledged or hypothecated by the Optionee during his
or her lifetime, whether by operation of law or otherwise, or be made subject to
execution, attachment or similar process.

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     (i) Termination of Service (Except by Death). Except as may be provided in
the applicable Stock Option Agreement, if an Optionee's Service terminates for
any reason other than the Optionee's death, then such Optionee's Option(s) shall
expire on the earliest of the following occasions:

          (i) The expiration date determined pursuant to Subsection (g) above;

          (ii) The date 90 days after the termination of the Optionee's Service
     for any reason other than Total and Permanent Disability; or

          (iii) The date six months after the termination of the Optionee's
     Service by reason of Total and Permanent Disability.

The Optionee may exercise all or part of his or her Option(s) at any time before
the expiration of such Option(s) under the preceding sentence, but only to the
extent that such Option(s) had become exercisable before the Optionee's Service
terminated or became exercisable as a result of the termination. The balance of
such Option(s) shall lapse when the Optionee's Service terminates. In the event
that the Optionee dies after the termination of the Optionee's Service but
before the expiration of the Optionee's Option(s), all or part of such Option(s)
may be exercised (prior to expiration) by the executors or administrators of the
Optionee's estate or by any person who has acquired such Option(s) directly from
the Optionee by bequest, beneficiary designation or inheritance, but only to the
extent that such Option(s) had become exercisable before the Optionee's Service
terminated or became exercisable as a result of the termination.

     (j) Leaves of Absence. Except as may be provided in the applicable Stock
Option Agreement, for purposes of Subsection (i) above, Service shall be deemed
to continue while the Optionee is on military leave, sick leave or other bona
fide leave of absence (as determined by the Committee). The foregoing
notwithstanding, in the case of an ISO granted under the Plan, Service shall not
be deemed to continue beyond the first 90 days of such leave, unless the
Optionee's reemployment rights are guaranteed by statute or by contract.

     (k) Death of Optionee. Except as may be provided in the applicable Stock
Option Agreement, if an Optionee dies while he or she is in Service, then such
Optionee's Option(s) shall expire on the earlier of the following dates:

          (i) The expiration date determined pursuant to Subsection (g) above;
     or

          (ii) The date six months after the Optionee's death.

All or part of the Optionee's Option(s) may be exercised at any time before the
expiration of such Option(s) under the preceding sentence by the executors or
administrators of the Optionee's estate or by any person who has acquired such
Option(s) directly from the Optionee by bequest, beneficiary designation or
inheritance, but only to the extent that such Option(s) had become exercisable
before the Optionee's death or became exercisable as a result of the Optionee's
death. The balance of such Option(s) shall lapse when the Optionee dies.

     (l) No Rights as a Stockholder. An Optionee, or a transferee of an
Optionee, shall have no rights as a stockholder with respect to any Shares
covered by his or her Option until he or she

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becomes entitled, pursuant to the terms of such Option, to receive such Shares.
No adjustments shall be made, except as provided in Section 9.

     (m) Modification, Extension and Assumption of Options. Within the
limitations of the Plan, the Committee may modify, extend or assume outstanding
Options or may accept the cancellation of outstanding Options (whether granted
by the Company or another issuer) in return for the grant of new Options for the
same or a different number of Shares and at the same or a different Exercise
Price. The foregoing notwithstanding, no modification of an Option shall,
without the consent of the Optionee, impair such Optionee's rights or increase
his or her obligations under such Option.

     (n) Restrictions on Transfer of Shares. Any Shares issued upon exercise of
an Option may be subject to such special forfeiture conditions, rights of
repurchase, rights of first refusal and other transfer restrictions as the
Committee may determine. Such restrictions shall be set forth in the applicable
Stock Option Agreement and shall apply in addition to any general restrictions
that may apply to all holders of Shares.

SECTION 8.  PAYMENT FOR SHARES.

     (a) General Rule. The entire Purchase Price or Exercise Price of Shares
issued under the Plan shall be payable in lawful money of the United States of
America at the time when such Shares are purchased, except as provided in
Subsections (b), (c), (d), (e) and (f) below.

     (b) Surrender of Stock. To the extent that a Stock Option Agreement so
provides, payment may be made all or in part with Shares which have already been
owned by the Optionee or the Optionee's representative for more than six months
and which are surrendered to the Company in good form for transfer. Such Shares
shall be valued at their Fair Market Value on the date when the new Shares are
purchased under the Plan.

     (c) Services Rendered. At the discretion of the Committee, Shares may be
awarded under the Plan in consideration of services rendered to the Company or a
Subsidiary prior to the award. If Shares are awarded without the payment of a
Purchase Price in cash, the Committee shall make a determination (at the time of
the award) of the value of the services rendered by the Offeree and the
sufficiency of the consideration to meet the requirements of Section 6(c).

     (d) Promissory Note. To the extent that a Stock Option Agreement or Stock
Purchase Agreement so provides, a portion of the Exercise Price or Purchase
Price (as the case may be) of Shares issued under the Plan may be paid with a
full-recourse promissory note, provided that (i) the par value of such Shares
must be paid in lawful money of the United States of America at the time when
such Shares are purchased, (ii) the Shares are pledged as security for payment
of the principal amount of the promissory note and interest thereon and (iii)
the interest rate payable under the terms of the promissory note shall not be
less than the minimum rate (if any) required to avoid the imputation of
additional interest under the Code. Subject to the foregoing, the Committee (at
its sole discretion) shall specify the term, interest rate, amortization
requirements (if any) and other provisions of such note.

     (e) Exercise/Sale. To the extent that a Stock Option Agreement so provides,
payment may be made all or in part by the delivery (on a form prescribed by the
Company) of an irrevocable direction to a securities broker approved by the
Company to sell Shares and to deliver all or part of the sales proceeds to the
Company in payment of all or part of the Exercise Price and any

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withholding taxes.

     (f) Exercise/Pledge. To the extent that a Stock Option Agreement so
provides, payment may be made all or in part by the delivery (on a form
prescribed by the Company) of an irrevocable direction to pledge Shares to a
securities broker or lender approved by the Company, as security for a loan, and
to deliver all or part of the loan proceeds to the Company in payment of all or
part of the Exercise Price and any withholding taxes.

SECTION 9.  ADJUSTMENT OF SHARES.

     (a) General. In the event of a subdivision of the outstanding Stock, a
declaration of a dividend payable in Shares, a declaration of a dividend payable
in a form other than Shares in an amount that has a material effect on the value
of Shares, a combination or consolidation of the outstanding Stock into a lesser
number of Shares, a recapitalization, a spinoff, a reclassification or a similar
occurrence, the Committee shall make appropriate adjustments in one or more of
(i) the number of Shares available for future grants under Section 5, (ii) the
limit set forth in Section 7(b), (iii) the number of Shares covered by each
outstanding Option or (iv) the Exercise Price under each outstanding Option.

     (b) Reorganizations. In the event that the Company is a party to a merger
or other reorganization, outstanding Options shall be subject to the agreement
of merger or reorganization. Such agreement may provide, without limitation, (i)
for the assumption of outstanding Options by the surviving corporation or its
parent, (ii) for their continuation by the Company, if the Company is a
surviving corporation, (iii) for payment of a cash settlement equal to the
difference between the amount to be paid for one Share pursuant to such
agreement and the Exercise Price or (iv) for the acceleration of their
exercisability followed by the cancellation of Options not exercised, in all
cases without the Optionees' consent. Any cancellation shall not occur until
after such acceleration is effective and Optionees have been notified of such
acceleration.

     (c) Reservation of Rights. Except as provided in this Section 9, an
Optionee or Offeree shall have no rights by reason of (i) any subdivision or
consolidation of shares of stock of any class, (ii) the payment of any dividend
or (iii) any other increase or decrease in the number of shares of stock of any
class. 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 be made with respect to, the number or
Exercise Price of Shares subject to an Option. The grant of an Option pursuant
to the Plan 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.

SECTION 10.  SECURITIES LAWS.

     Shares shall not be issued under the Plan unless the issuance and delivery
of such Shares comply with (or are exempt from) all applicable requirements of
law, including (without limitation) the Securities Act of 1933, as amended, the
Exchange Act, the rules and regulations promulgated thereunder, state securities
laws and regulations, and the regulations of any stock exchange on which the
Company's securities may then be listed.

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SECTION 11.  NO EMPLOYMENT RIGHTS.

     No provision of the Plan, nor any right or Option granted under the Plan,
shall be construed to give any person any right to become, to be treated as, or
to remain an Employee. The Company and its Subsidiaries reserve the right to
terminate any person's Service at any time and for any reason.

SECTION 12.  DURATION AND AMENDMENTS.

     (a) Term of the Plan. The Plan, as amended and restated as set forth
herein, shall become effective as of February 15, 2001. In the event the
Company's stockholders fail to approve the amendment to the Plan increasing the
number of shares issuable hereunder at the 2001 annual meeting of stockholders,
any Option grants or Stock awards made in excess of an aggregate of 17,400,000
Shares shall be null and void. The Plan shall terminate automatically on
February 15, 2011 and may be terminated on any earlier date pursuant to
Subsection (b) below.

     (b) Right to Amend or Terminate the Plan. The Board of Directors may amend,
suspend or terminate the Plan at any time and for any reason. An amendment of
the Plan shall be subject to the approval of the Company's stockholders to the
extent required by applicable laws, regulations, rules, listing standards or
other requirements, including (without limitation) Rule 16b-3 under the Exchange
Act. Stockholder approval shall not be required for any other amendment of the
Plan.

     (c) Effect of Amendment or Termination. No Shares shall be issued or sold
under the Plan after the termination thereof, except upon exercise of an Option
granted prior to such termination. The termination of the Plan, or any amendment
thereof, shall not affect any Share previously issued or any Option previously
granted under the Plan.

SECTION 13.  EXECUTION.

     To record the amendment and restatement of the Plan by the Board of
Directors on February 15, 2001, the Company has caused its authorized officer to
execute the same.

                                        INCYTE GENOMICS, INC.



                                        By  /s/  ROY A. WHITFIELD
                                          --------------------------------------

                                        Its  Chief Executive Officer
                                           -------------------------------------


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