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                                                                      Exhibit 99

                              CURAGEN CORPORATION
                              AMENDED AND RESTATED
               1997 EMPLOYEE, DIRECTOR AND CONSULTANT STOCK PLAN



1.   DEFINITIONS.
     -----------

     Unless otherwise specified or unless the context otherwise requires, the
     following terms, as used in this CuraGen Corporation 1997 Employee,
     Director and Consultant Stock Plan, have the following meanings:

          Administrator means the Board of Directors, unless it has delegated
          -------------
          power to act on its behalf to the Committee, in which case the
          Administrator means the Committee.

          Affiliate means a corporation which, for purposes of Section 424 of
          ---------
          the Code, is a parent or subsidiary of the Company, direct or
          indirect.

          Board of Directors means the Board of Directors of the Company.
          ------------------

          Code means the United States Internal Revenue Code of 1986, as
          ----
          amended.

          Committee means the committee of the Board of Directors to which the
          ---------
          Board of Directors has delegated power to act under or pursuant to the
          provisions of the Plan.

          Common Stock means shares of the Company's voting common stock, $.01
          ------------
          par value per share.

          Company means CuraGen Corporation, a Delaware corporation.
          -------

          Disability or Disabled means permanent and total disability as defined
          ----------    --------
          in Section 22(e)(3) of the Code.

          Fair Market Value of a Share of Common Stock means:
          -----------------

          (1) If the Common Stock is listed on a national securities exchange or
          traded in the over-the-counter market and sales prices are regularly
          reported for the Common Stock, the closing or last price of the Common
          Stock on the Composite Tape or other comparable reporting system for
          the trading day immediately preceding the applicable date;
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          (2) If the Common Stock is not traded on a national securities
          exchange but is traded on the over-the-counter market, if sales prices
          are not regularly reported for the Common Stock for the trading day
          referred to in clause (1), and if bid and asked prices for the Common
          Stock are regularly reported, the mean between the bid and the asked
          price for the Common Stock at the close of trading in the over-the-
          counter market for the trading day on which Common Stock was traded
          immediately preceding the applicable date; and

          (3) If the Common Stock is neither listed on a national securities
          exchange nor traded in the over-the-counter market, such value as the
          Administrator, in good faith, shall determine.

          ISO means an option meant to qualify as an incentive stock option
          ---
          under Section 422 of the Code.

          Key Employee means an employee of the Company or of an Affiliate
          ------------
          (including, without limitation, an employee who is also serving as an
          officer or director of the Company or of an Affiliate), designated by
          the Administrator to be eligible to be granted one or more Stock
          Rights under the Plan.

          Non-Qualified Option means an option which is not intended to qualify
          --------------------
          as an ISO.

          Option means an ISO or Non-Qualified Option granted under the Plan.
          ------

          Option Agreement means an agreement between the Company and a
          ----------------
          Participant delivered pursuant to the Plan, in such form as the
          Administrator shall approve.

          Participant means a Key Employee, director or consultant to whom one
          -----------
          or more Stock Rights are granted under the Plan.  As used herein,
          "Participant" shall include "Participant's Survivors" where the
          context requires.

          Plan means this CuraGen Corporation 1997 Employee, Director and
          ----
          Consultant Stock Plan.

          Shares means shares of the Common Stock as to which Stock Rights have
          ------
          been or may be granted under the Plan or any shares of capital stock
          into which the Shares are changed or for which they are exchanged
          within the provisions of Paragraph 3 of the Plan.  The Shares issued
          under the Plan may be authorized and unissued shares or shares held by
          the Company in its treasury, or both.

          Stock Grant  means a grant by the Company of Shares under the Plan.
          -----------

          Stock Grant Agreement means an agreement between the Company and a
          ---------------------
          Participant delivered pursuant to the Plan, in such form as the
          Administrator shall approve.

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          Stock Right means a right to Shares of the Company granted pursuant to
          -----------
          the Plan -- an ISO, a Non-Qualified Option or a Stock Grant.

          Survivors means a deceased Participant's legal representatives and/or
          ---------
          any person or persons who acquired the Participant's rights to a Stock
          Right by will or by the laws of descent and distribution.


2.   PURPOSES OF THE PLAN.
     --------------------

     The Plan is intended to encourage ownership of Shares by Key Employees and
directors of and certain consultants to the Company in order to attract such
people, to induce them to work for the benefit of the Company or of an Affiliate
and to provide additional incentive for them to promote the success of the
Company or of an Affiliate.  The Plan provides for the granting of ISOs, Non-
Qualified Options and Stock Grants.


3.   SHARES SUBJECT TO THE PLAN.
     --------------------------

     The number of Shares which may be issued from time to time pursuant to this
Plan shall be 3,500,000 or the equivalent of such number of Shares after the
Administrator, in its sole discretion, has interpreted the effect of any stock
split, stock dividend, combination, recapitalization or similar transaction in
accordance with Paragraph 23 of the Plan.

     If an Option ceases to be "outstanding", in whole or in part, or if the
Company shall reacquire any Shares issued pursuant to a Stock Grant, the Shares
which were subject to such Option and any Shares so reacquired by the Company
shall be available for the granting of other Stock Rights under the Plan.  Any
Option shall be treated as "outstanding" until such Option is exercised in full,
or terminates or expires under the provisions of the Plan, or by agreement of
the parties to the pertinent Option Agreement.


4.   ADMINISTRATION OF THE PLAN.
     --------------------------

     The Administrator of the Plan will be the Board of Directors, except to the
extent the Board of Directors delegates its authority to the Committee, in which
case the Committee shall be the Administrator.  Subject to the provisions of the
Plan, the Administrator is authorized to:

     a.   Interpret the provisions of the Plan or of any Option or Stock Grant
          and to make all rules and determinations which it deems necessary or
          advisable for the administration of the Plan;

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     b.   Determine which employees of the Company or of an Affiliate shall be
          designated as Key Employees and which of the Key Employees, directors
          and consultants shall be granted Stock Rights;

     c.   Determine the number of Shares for which a Stock Right or Stock Rights
          shall be granted, provided, however, that in no event shall Stock
          Rights with respect to more than 750,000 shares be granted to any
          Participant in any fiscal year; and

     d.   Specify the terms and conditions upon which a Stock Right or Stock
          Rights may be granted;

provided, however, that all such interpretations, rules, determinations, terms
and conditions shall be made and prescribed in the context of preserving the tax
status under Section 422 of the Code of those Options which are designated as
ISOs.  Subject to the foregoing, the interpretation and construction by the
Administrator of any provisions of the Plan or of any Stock Right granted under
it shall be final, unless otherwise determined by the Board of Directors, if the
Administrator is the Committee.



5.   ELIGIBILITY FOR PARTICIPATION.
     -----------------------------

     The Administrator will, in its sole discretion, name the Participants in
the Plan, provided, however, that each Participant must be a Key Employee,
director or consultant of the Company or of an Affiliate at the time a Stock
Right is granted.  Notwithstanding the foregoing, the Administrator may
authorize the grant of a Stock Right to a person not then an employee, director
or consultant of the Company or of an Affiliate; provided, however, that the
actual grant of such Stock Right shall be conditioned upon such person becoming
eligible to become a Participant at or prior to the time of the delivery of the
Agreement evidencing such Stock Right.  ISOs may be granted only to Key
Employees.  Non-Qualified Options and Stock Grants may be granted to any Key
Employee, director or consultant of the Company or an Affiliate.  The granting
of any Stock Right to any individual shall neither entitle that individual to,
nor disqualify him or her from, participation in any other grant of Stock
Rights.



6.   TERMS AND CONDITIONS OF OPTIONS.
     -------------------------------

     Each Option shall be set forth in writing in an Option Agreement, duly
executed by the Company and, to the extent required by law or requested by the
Company, by the Participant.  The Administrator may provide that Options be
granted subject to such conditions as the Administrator may deem appropriate
including, without limitation, subsequent approval by the shareholders of the
Company of this Plan or any amendments thereto.  The Option Agreements shall be
subject to at least the following terms and conditions:

     A.   Non-Qualified Options:  Each Option intended to be a Non-Qualified
          ---------------------
          Option shall be subject to the terms and conditions which the
          Administrator determines to be

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          appropriate and in the best interest of the Company, subject to the
          following minimum standards for any such Non-Qualified Option:

          a.   Option Price: Each Option Agreement shall state the option price
               (per share) of the Shares covered by each Option, which option
               price shall be determined by the Administrator but shall not be
               less than the par value per share of Common Stock.

          b.   Each Option Agreement shall state the number of Shares to which
               it pertains;

          c.   Each Option Agreement shall state the date or dates on which it
               first is exercisable and the date after which it may no longer be
               exercised, and may provide that the Option rights accrue or
               become exercisable in installments over a period of months or
               years, or upon the occurrence of certain conditions or the
               attainment of stated goals or events; and

          d.   Exercise of any Option may be conditioned upon the Participant's
               execution of a Share purchase agreement in form satisfactory to
               the Administrator providing for certain protections for the
               Company and its other shareholders, including requirements that:

               i.   The Participant's or the Participant's Survivors' right to
                    sell or transfer the Shares may be restricted; and

               ii.  The Participant or the Participant's Survivors may be
                    required to execute letters of investment intent and must
                    also acknowledge that the Shares will bear legends noting
                    any applicable restrictions.

          e.   Directors' Options:  Each director of the Company who is serving
               ------------------
               on the Board of Directors on October 6, 1997 and who is not an
               employee of or consultant to the Company or any Affiliate, shall
               be granted a Non-Qualified Option to purchase 5,000 Shares as of
               such date.  In addition, each director of the Company who is
               elected or appointed to the Board of Directors after October 6,
               1997 and who is not an employee of or consultant to the Company
               or any Affiliate, upon first being elected or appointed to the
               Board of Directors, shall be granted a Non-Qualified Option to
               purchase 20,000 Shares as of the date of election or appointment.
               Each Option described in the foregoing two sentences shall (i)
               have an exercise price equal to the Fair Market Value (per share)
               of the Shares on the date of grant of the Option, (ii) have a
               term of ten years, and (iii) become cumulatively exercisable as
               follows: (x) one-third shall vest immediately on the date of
               grant, (y) one-third shall vest on the first anniversary of the
               date of grant, and (z) one-third shall vest on the second
               anniversary of the date of grant.

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               Immediately following the 1998 annual meeting of stockholders (or
               special meeting in lieu of an annual meeting), and until the 1999
               annual meeting of stockholders, each Continuing Director (as
               defined below) will be granted a Non-Qualified Option to purchase
               5,000 Shares. Immediately following each annual meeting of
               stockholders (or special meeting in lieu of an annual meeting),
               commencing with the 1999 annual meeting, each Continuing Director
               (as defined below) will be granted a Non-Qualified Option to
               purchase 7,500 Shares. As used herein, the term "Continuing
               Director" shall mean a director who (i) is serving as a director
               immediately following such annual or special meeting but was not
               first elected at such annual or special meeting, (ii) has been in
               continued and uninterrupted service as a director of the Company
               since his or her initial election or appointment and (iii) is not
               an employee of or consultant to the Company or any Affiliate.
               Each such Option shall (i) have an exercise price equal to the
               Fair Market Value (per share) of the Shares on the date of grant
               of the Option, (ii) have a term of ten years, and (iii) be
               immediately exercisable in full.

               Any director entitled to receive an Option under this
               subparagraph may elect to decline the Option.

     Except as otherwise provided in the pertinent Option Agreement, if a
     director who receives Options pursuant to this subparagraph:

               a.   ceases to be a member of the Board of Directors for any
                    reason other than death or Disability, any then unexercised
                    Options granted to such director may be exercised by the
                    director within a period of ninety (90) days after the date
                    the director ceases to be a member of the Board of
                    Directors, but only to the extent of the number of Shares
                    with respect to which the Options are exercisable on the
                    date the director ceases to be a member of the Board of
                    Directors, and in no event later than the expiration date of
                    the Option; or

               b.   ceases to be a member of the Board of Directors by reason of
                    his or her death or Disability, any then unexercised Options
                    granted to such director may be exercised by the director
                    (or by the director's personal representative, or the
                    director's Survivors) within a period of one hundred eighty
                    (180) days after the date the director ceases to be a member
                    of the Board of Directors, but only to the extent of the
                    number of Shares with respect to which the Options are
                    exercisable on the date the director ceases to be a member
                    of the Board of Directors, and in no event later than the
                    expiration date of the Option.

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<PAGE>

     B.   ISOs:  Each Option intended to be an ISO shall be issued only to a Key
          ----
          Employee and be subject to at least the following terms and
          conditions, with such additional restrictions or changes as the
          Administrator determines are appropriate but not in conflict with
          Section 422 of the Code and relevant regulations and rulings of the
          Internal Revenue Service:

          a.   Minimum standards:  The ISO shall meet the minimum standards
               required of Non-Qualified Options, as described in Paragraph 6(A)
               above, except clauses (a) and (e) thereunder.

          b.   Option Price:  Immediately before the Option is granted, if the
               Participant owns, directly or by reason of the applicable
               attribution rules in Section 424(d) of the Code:

               i.   Ten percent (10%) or less of the total combined voting power
                                      -------
                    of all classes of stock of the Company or an Affiliate, the
                    Option price per share of the Shares covered by each Option
                    shall not be less than one hundred percent (100%) of the
                    Fair Market Value per share of the Shares on the date of the
                    grant of the Option.

               ii.  More than ten percent (10%) of the total combined voting
                    power of all classes of stock of the Company or an
                    Affiliate, the Option price per share of the Shares covered
                    by each Option shall not be less than one hundred ten
                    percent (110%) of the said Fair Market Value on the date of
                    grant.

          c.   Term of Option:  For Participants who own

               i.   Ten percent (10%) or less of the total combined voting power
                                      -------
                    of all classes of stock of the Company or an Affiliate, each
                    Option shall terminate not more than ten (10) years from the
                    date of the grant or at such earlier time as the Option
                    Agreement may provide.

               ii.  More than ten percent (10%) of the total combined voting
                    power of all classes of stock of the Company or an
                    Affiliate, each Option shall terminate not more than five
                    (5) years from the date of the grant or at such earlier time
                    as the Option Agreement may provide.

          d.   Limitation on Yearly Exercise:  The Option Agreements shall
               restrict the amount of Options which may be exercisable in any
               calendar year (under this or any other ISO plan of the Company or
               an Affiliate) so that the aggregate Fair Market Value (determined
               at the time each ISO is granted) of the stock with respect to
               which ISOs are exercisable for the first time by the Participant
               in any calendar year does not exceed one hundred thousand

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               dollars ($100,000), provided that this subparagraph (d) shall
               have no force or effect if its inclusion in the Plan is not
               necessary for Options issued as ISOs to qualify as ISOs pursuant
               to Section 422(d) of the Code.


7.   TERMS AND CONDITIONS OF STOCK GRANTS.
     ------------------------------------

     Each offer of a Stock Grant to a Participant shall state the date prior to
which the Stock Grant must be accepted by the Participant, and the principal
terms of each Stock Grant shall be set forth in a Stock Grant Agreement, duly
executed by the Company and, to the extent required by law or requested by the
Company, by the Participant.  The Stock Grant Agreement shall be in a form
approved by the Administrator and shall contain terms and conditions which the
Administrator determines to be appropriate and in the best interest of the
Company, subject to the following minimum standards:

     (a)  Each Stock Grant Agreement shall state the purchase price (per share),
          if any, of the Shares covered by each Stock Grant, which purchase
          price shall be determined by the Administrator but shall not be less
          than the minimum consideration required by the Delaware General
          Corporation Law on the date of the grant of the Stock Grant;

     (b)  Each Stock Grant Agreement shall state the number of Shares to which
          the Stock Grant pertains; and

     (c)  Each Stock Grant Agreement shall include the terms of any right of the
          Company to reacquire the Shares subject to the Stock Grant, including
          the time and events upon which such rights shall accrue and the
          purchase price therefor, if any.


8.   EXERCISE OF OPTIONS AND ISSUE OF SHARES.
     ---------------------------------------

     An Option (or any part or installment thereof) shall be exercised by giving
written notice to the Company at its principal executive office address,
together with provision for payment of the full purchase price in accordance
with this Paragraph for the Shares as to which the Option is being exercised,
and upon compliance with any other condition(s) set forth in the Option
Agreement.  Such written notice shall be signed by the person exercising the
Option, shall state the number of Shares with respect to which the Option is
being exercised and shall contain any representation required by the Plan or the
Option Agreement.  Payment of the purchase price for the Shares as to which such
Option is being exercised shall be made (a) in United States dollars in cash or
by check, or (b) at the discretion of the Administrator, through delivery of
shares of Common Stock having a Fair Market Value equal as of the date of the
exercise to the cash exercise price of the Option, or (c) at the discretion of
the Administrator, by having the Company retain from the shares otherwise
issuable upon exercise of the Option, a number of shares having a Fair Market
Value equal as of the date of exercise to the exercise price of the Option, or
(d) at the discretion of the Administrator, by delivery of the grantee's
personal recourse note bearing

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interest payable not less than annually at no less than 100% of the applicable
Federal rate, as defined in Section 1274(d) of the Code, or (e) at the
discretion of the Administrator, in accordance with a cashless exercise program
established with a securities brokerage firm, and approved by the Administrator,
or (f) at the discretion of the Administrator, by any combination of (a), (b),
(c), (d) and (e) above. Notwithstanding the foregoing, the Administrator shall
accept only such payment on exercise of an ISO as is permitted by Section 422 of
the Code.

     The Company shall then reasonably promptly deliver the Shares as to which
such Option was exercised to the Participant (or to the Participant's Survivors,
as the case may be).  In determining what constitutes "reasonably promptly," it
is expressly understood that the issuance and delivery of the Shares may be
delayed by the Company in order to comply with any law or regulation (including,
without limitation, state securities or "blue sky" laws) which requires the
Company to take any action with respect to the Shares prior to their issuance.
The Shares shall, upon delivery, be evidenced by an appropriate certificate or
certificates for fully paid, non-assessable Shares.

     The Administrator shall have the right to accelerate the date of exercise
of any installment of any Option; provided that the Administrator shall not
accelerate the exercise date of any installment of any Option granted to any Key
Employee as an ISO (and not previously converted into a  Non-Qualified Option
pursuant to Paragraph 26) if such acceleration would violate the annual vesting
limitation contained in Section 422(d) of the Code, as described in Paragraph
6.B.d.

     The Administrator may, in its discretion, amend any term or condition of an
outstanding Option provided (i) such term or condition as amended is permitted
by the Plan, (ii) any such amendment shall be made only with the consent of the
Participant to whom the Option was granted, or in the event of the death of the
Participant, the Participant's Survivors, if the amendment is adverse to the
Participant, and (iii) any such amendment of any ISO shall be made only after
the Administrator, after consulting the counsel for the Company, determines
whether such amendment would constitute a "modification" of any Option which is
an ISO (as that term is defined in Section 424(h) of the Code) or would cause
any adverse tax consequences for the holder of such ISO.


9.   ACCEPTANCE OF STOCK GRANT AND ISSUE OF SHARES.
     ---------------------------------------------

     A Stock Grant (or any part or installment thereof) shall be accepted by
executing the Stock Grant Agreement and delivering it to the Company at its
principal office address, together with provision for payment of the full
purchase price, if any, in accordance with this Paragraph for the Shares as to
which such Stock Grant is being accepted, and upon compliance with any other
conditions set forth in the Stock Grant Agreement.  Payment of the purchase
price for the Shares as to which such Stock Grant is being accepted shall be
made (a) in United States dollars in cash or by check, or (b) at the discretion
of the Administrator, through delivery of shares of Common Stock having a fair
market value equal as of the date of acceptance of the Stock Grant to the
purchase price of the Stock Grant determined in good faith by the Administrator,
or (c) at

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the discretion of the Administrator, by delivery of the grantee's personal
recourse note bearing interest payable not less than annually at no less than
100% of the applicable Federal rate, as defined in Section 1274(d) of the Code,
or (d) at the discretion of the Administrator, by any combination of (a), (b)
and (c) above.

     The Company shall then reasonably promptly deliver the Shares as to which
such Stock Grant was accepted to the Participant (or to the Participant's
Survivors, as the case may be), subject to any escrow provision set forth in the
Stock Grant Agreement.  In determining what constitutes "reasonably promptly,"
it is expressly understood that the issuance and delivery of the Shares may be
delayed by the Company in order to comply with any law or regulation (including,
without limitation, state securities or "blue sky" laws) which requires the
Company to take any action with respect to the Shares prior to their issuance.

     The Administrator may, in its discretion, amend any term or condition of an
outstanding Stock Grant or Stock Grant Agreement provided (i) such term or
condition as amended is permitted by the Plan, and (ii) any such amendment shall
be made only with the consent of the Participant to whom the Stock Grant was
made, if the amendment is adverse to the Participant.


10.  RIGHTS AS A SHAREHOLDER.
     -----------------------

     No Participant to whom a Stock Right has been granted shall have rights as
a shareholder with respect to any Shares covered by such Stock Right, except
after due exercise of the Option or acceptance of the Stock Grant and tender of
the full purchase price, if any, for the Shares being purchased pursuant to such
exercise or acceptance and registration of the Shares in the Company's share
register in the name of the Participant.


11.  ASSIGNABILITY AND TRANSFERABILITY OF STOCK RIGHTS.
     -------------------------------------------------

     By its terms, a Stock Right granted to a Participant shall not be
transferable by the Participant other than (i) by will or by the laws of descent
and distribution, or (ii) as otherwise determined by the Administrator and set
forth in the applicable Option Agreement or Stock Grant Agreement.  The
designation of a beneficiary of a Stock Right by a Participant shall not be
deemed a transfer prohibited by this Paragraph.  Except as provided above, a
Stock Right shall only be exercisable or may only be accepted, during the
Participant's lifetime, by such Participant (or by his or her legal
representative) and shall not be assigned, pledged or hypothecated in any way
(whether by operation of law or otherwise) and shall not be subject to
execution, attachment or similar process.  Any attempted transfer, assignment,
pledge, hypothecation or other disposition of any Stock Right or of any rights
granted thereunder contrary to the provisions of this Plan, or the levy of any
attachment or similar process upon a Stock Right, shall be null and void.

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<PAGE>

12.  EFFECT ON OPTIONS OF TERMINATION OF SERVICE OTHER THAN "FOR CAUSE" OR DEATH
     ---------------------------------------------------------------------------
     OR DISABILITY.
     -------------

     Except as otherwise provided in the pertinent Option Agreement in the event
of a termination of service (whether as an employee, director or consultant)
with the Company or an Affiliate before the Participant has exercised an Option,
the following rules apply:


     a.   A Participant who ceases to be an employee, director or consultant of
          the Company or of an Affiliate (for any reason other than termination
          "for cause", Disability, or death for which events there are special
          rules in Paragraphs 13, 14, and 15, respectively), may exercise any
          Option granted to him or her to the extent that the Option is
          exercisable on the date of such termination of service, but only
          within such term as the Administrator has designated in the pertinent
          Option Agreement.

     b.   Except as provided in subparagraph (c) below, or Paragraph 14 or 15,
          In no event may an Option Agreement provide, if an Option is intended
          to be an ISO, that the time for exercise be later than three (3)
          months after the Participant's termination of employment.

     c.   The provisions of this Paragraph, and not the provisions of Paragraph
          14 or 15, shall apply to a Participant who subsequently becomes
          Disabled or dies after the termination of employment, director status
          or consultancy, provided, however, in the case of a Participant's
          Disability or death within three (3) months after the termination of
          employment, director status or consultancy, the Participant or the
          Participant's Survivors may exercise the Option within one (1) year
          after the date of the Participant's termination of employment, but in
          no event after the date of expiration of the term of the Option.

     d.   Notwithstanding anything herein to the contrary, if subsequent to a
          Participant's termination of employment, termination of director
          status or termination of consultancy, but prior to the exercise of an
          Option, the Board of Directors determines that, either prior or
          subsequent to the Participant's termination, the Participant engaged
          in conduct which would constitute "cause", then such Participant shall
          forthwith cease to have any right to exercise any Option.

     e.   A Participant to whom an Option has been granted under the Plan who is
          absent from work with the Company or with an Affiliate because of
          temporary disability (any disability other than a permanent and total
          Disability as defined in Paragraph 1 hereof), or who is on leave of
          absence for any purpose, shall not, during the period of any such
          absence, be deemed, by virtue of such absence alone, to have
          terminated such Participant's employment, director status or
          consultancy with the Company or with an Affiliate, except as the
          Administrator may otherwise expressly provide.

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