<PAGE>


                                                                   EXHIBIT 10.30

     THIS EMPLOYMENT AGREEMENT ("Agreement") is made and entered into as of
March 4, 2002 between CuraGen Corporation, a corporation organized under the
laws of the State of Delaware, with its principal place of business at 555 Long
Wharf Drive, New Haven, Connecticut (the "Company"), and Jonathan M. Rothberg
("Executive").

     WHEREAS, the Executive desires to be employed by the Company, subject to
the terms and conditions of this Agreement; and the Company desires to retain
the Executive's services, subject to the terms and conditions of this Agreement.

     THEREFORE, the Company and the Executive, intending to be legally bound,
hereby agree as follows:

1. Employment; Duties and Responsibilities
   ---------------------------------------

     A) The Company shall employ the Executive, and the Executive shall serve
the Company, as Chairman, President and Chief Executive Officer, with such
duties and responsibilities as may be assigned to the Executive by the Board of
Directors ("BOD") of the Company and are typically associated with a position of
that nature.

     B) The Executive shall devote his best efforts and all of his business time
to the performance of his duties under this Agreement and shall perform them
faithfully, diligently and competently in a manner consistent with the policies
and goals of the Company as determined from time to time by the BOD.

     C) The Executive shall report to the BOD of the Company.

     D) The Executive shall not engage in any activities outside the scope of
his employment that would detract from, or interfere with, the fulfillment of
his responsibilities or duties under this Agreement.



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     E) The Executive shall not serve as a director (or the equivalent position)
of any company or entity and shall not render services of a business,
professional or commercial nature to any other person or firm without prior
written consent of the BOD. Such consent shall not be unreasonably withheld.

     F) The Executive shall not receive fees or other remuneration for work
performed either within or outside the scope of his employment except for
not-for-profit entities without prior written consent of the BOD. Such consent
shall not be unreasonably withheld.

2. Term of Employment
   ------------------

     A) The Executive's employment by the Company under this Agreement shall
commence on the date of this Agreement and, subject to the earlier termination
pursuant to section 10 shall terminate on December 31, 2002; provided, however,
that commencing on January 1, 2003 and each January 1 thereafter the term of
this Agreement shall be extended for one (1) additional year unless, not later
than October 31 of the preceding year, the Company or the Executive shall have
given written notice that the Company or the Executive does not wish to extend
this Agreement.




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3. Compensation
   ------------

     As full compensation for all services rendered by the Executive to the
Company under this Agreement, the Company shall pay the Executive the
compensation set forth in Schedule A attached and incorporated into this
Agreement. This schedule may be amended from time to time in writing by the
Company and the Executive.

4. Fringe Benefits
   ---------------

     A) The Executive shall be entitled to participate in all health and welfare
benefit plans provided by the Company to its employees.

     B) The Executive shall be entitled to participate in all pension plans
provided by the Company to its employees.

     C) The Company may, at its sole option, devise a benefit plan for its
executives or senior managers. The Executive shall be entitled to participate in
benefit plans provided by the Company to its executives or senior managers.

     D) The Executive shall be entitled to a minimum of four (4) weeks paid
vacation time annually, to be taken at times selected by him.

5. Expenses
   --------

     The Company shall reimburse the Executive for all reasonable
and necessary expenses incurred by him in connection with the performance of his
services for the Company in accordance with the Company's policies, upon
submission of appropriate expense reports and documentation in accordance with
the Company's policies and procedures.



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6. Disability or Death
   -------------------

     A) If, as the result of any physical or mental disability, the Executive
shall have failed or is unable to perform his duties for a period of ninety (90)
consecutive days, the Company may, by notice to the Executive, terminate his
employment under this Agreement as of the date of the notice without any further
payment or the furnishing of any benefit by the Company under this Agreement
(other than accrued and unpaid base salary and expenses and benefits which have
accrued pursuant to any plan or by law).

     B) The term of the Executive's employment under this Agreement shall
terminate upon his death without any further payment or the furnishing of any
benefit by the Company under this Agreement (other than accrued and unpaid base
salary and commission and expenses and benefits which have accrued pursuant to
any plan or by law). This provision shall not be read to change the terms of any
other agreement between the Executive and the Company, including any stock
option plans, which shall be governed by its terms. Unless expressly provided
for in such agreements, the death of the Executive shall not terminate such
agreements.

7. Patents, Copyrights and Intellectual Property
   ---------------------------------------------

     A) The Executive shall promptly disclose to the Company all Inventions.
Inventions shall mean, for purposes of this paragraph, inventions, discoveries,
developments, methods and processes (whether or not patenable or copyrightable
or constituting trade secrets) conceived, made or discovered by the Executive
(whether alone or with others) while employed by the Company that relate,
directly or indirectly, to the past, present, or future business activities,
research, product design or development, personnel, and business opportunities
of the Company, or result from tasks assigned to the Executive by the Company or
done by the Executive for or on behalf of the Company. The Executive hereby
assigns and agrees to assign to the Company



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(or as otherwise directed by the Company) his full right, title and interest in
and to all Inventions. The Executive agrees to execute any and all applications
for domestic and foreign patents, copyrights or other proprietary rights and to
do such other acts (including, among others, the execution and delivery of
instruments of further assurance or confirmation) requested by the Company to
assign the Inventions to the Company and to permit the Company to file, obtain
and enforce any patents, copyrights or other proprietary rights in the
Inventions. The Executive agrees to make and maintain adequate and current
records of all Inventions, in the form of notes, sketches, drawings, or reports
relating thereto, which records shall be and remain the property of and
available to the Company at all times.



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8. Proprietary and Trade Secret Information
   ----------------------------------------

     A) The Executive agrees that he will keep confidential and will not make
any unauthorized use or disclosure, or use for his own benefit or the benefit of
others, during or subsequent to his employment of any research, development,
engineering and manufacturing data, plans, designs, formulae, processes,
specifications, techniques, trade secrets, financial information, customer or
supplier lists or other information that becomes known to him as a result of his
employment with the Company which is the property of the Company or any of its
clients, customers, consultants, licensors, licensees, or affiliates, provided
nothing herein shall be construed to prevent the Executive from using his
general knowledge and skill after termination of his employment whether acquired
prior to or during his employment by the Company.

     B) Proprietary information subject to paragraph 8(A) does not include
information that: (i) is or later becomes available to the public through no
breach of this Agreement by the Employee; (ii) is obtained by the Executive from
a third party who had the legal right to disclose the information to the
Executive; or (iii) is required to be disclosed by law, government regulation,
or court order.





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     C) Upon leaving the employment of the Company, the Executive will not
remove from the Company premises, either directly or indirectly, any drawings,
writings, prints, any documents or anything containing, embodying, or disclosing
any confidential or proprietary information or any of the Company's trade
secrets unless express written permission is given by the Board of Directors.
Upon termination of his employment, the Executive shall return to the Company
any and all documents and materials that are the property of the Company or its
customers, licensees, licensors or affiliates or which contain information that
is the property of the Company.

9. Covenant Not to Compete
   -----------------------

     A) While in the employ of the Company and for a period of one year or the
maximum period permitted by applicable law (whichever is shorter) following
termination of his employment with the Company, the Executive shall not, without
the approval of the Company, alone or as a partner, officer, director,
consultant, employee, stockholder or otherwise, engage in any employment,
consulting or business activity or occupation that is or is intended to be
directly competitive with the business of the Company, as being considered,
researched, developed, marketed and/or sold at the time of termination;
provided, however, that the holding by the Executive of any investment in any
security shall not be deemed to be a violation of this section if such
investment does not constitute over one percent (1%) of the outstanding issue of
such security. The restriction shall run for a period of one year after said
termination, and if there shall be any violation hereof during said period, then
for a period of one year after cessation of such violation.

     B) While in the employ of the Company, the Executive shall promptly notify
the Company, if the Executive, alone or as a partner, officer, director,
consultant, employee,



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stockholder or otherwise, engages in any employment, consulting or business
activity or occupation outside his employment by the Company.

     C) The Executive shall not, directly or indirectly, either during the term
of the Executive's employment under this Agreement or for a period of one (1)
year thereafter, solicit, directly or indirectly, the services of any person who
was a full-time employee of the Company, its subsidiaries, divisions or
affiliates, or solicit the business of any person who was a client or customer
of the Company, its subsidiaries, divisions or affiliates, in each case at any
time during the last year of the term of the Executive's employment under this
Agreement. The Executive shall not, directly or indirectly, either during the
term of the Executive's employment under this Agreement or for a period of one
(1) year thereafter, employ, directly or indirectly, the services of any person
who was a full-time employee of the Company, its subsidiaries, divisions or
affiliates, or solicit the business of any person who was a client or customer
of the Company, its subsidiaries, divisions or affiliates, in each case at any
time during the last year of the term of the Executive's employment under this
Agreement. For purposes of this Agreement, the term "person" shall include
natural persons, corporations, business trusts, associations, sole
proprietorships, unincorporated organizations, partnerships, joint ventures and
governments or any agencies, instrumentalities or political subdivisions
thereof.

     D) The Executive acknowledges and agrees that the covenants in this section
are necessary for the protection of the legitimate business interests of the
Company and that the covenants are reasonable in all respects. The Executive
further acknowledges and agrees that, if his employment by the Company is
terminated, his experience and capabilities are such that he is both qualified
and willing to seek and obtain employment involving business activities which



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will not violate any covenant on his part to be observed hereunder and that a
court decree enjoining any such violation will not prevent him from earning a
reasonable livelihood.

     E) Just compensation for the duties under this paragraph is included in the
salary and benefits provided herein.

     F) If the Executive is terminated as a result of a Change of Control, as
defined in this Agreement, this Section, titled "Covenant Not to Compete," shall
not be applicable.

10. Termination
    -----------

     A) The Company shall have the right to terminate this Agreement and the
Executive's employment with the Company for performance reasons or cause. For
purposes of this Agreement, the term "performance reasons" shall mean
termination of the Executive's employment upon the assessment of the Board of
Directors, or a Committee of the Board of Directors, that the Executive has
failed to satisfactorily perform the essential functions of the Executive's
position. Such a determination shall be made using acceptable business practices
and sound management principles and shall not be made in bad faith or
arbitrarily.

     B) For purposes of this Agreement, the term "for cause" shall mean the
Executive's willfully engaging in conduct demonstrably and materially injurious
to the Company, monetarily or otherwise, provided that the Executive receives a
copy of a resolution duly adopted by the unanimous affirmative vote of the
entire membership of the Board of Directors of the Company at a meeting of the
Board of the Company called and held for such purpose after the Executive has
been given reasonable notice of such meeting and has been given an opportunity,
together with his counsel, to be heard by the Board of the Company, finding that
in the good faith opinion of the Board of the Company the Executive was guilty
of the conduct set forth and specifying the particulars thereof in detail.



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     C) The Executive's act, or failure to act, shall be deemed "willful" if the
Executive was not acting in good faith or acting without reasonable belief that
the Executive's action or omission was in the best interests of the Company. Any
act or failure to act based on authority given pursuant to a resolution duly
adopted by the Board of the Company, or based upon the advice of counsel for the
Company shall be conclusively presumed to have been done by the Executive in
good faith and in the best interests of the Company.

     D) If the Executive is terminated for cause, the Company shall not be
obligated to make any further payment to the Executive (other than accrued and
unpaid base salary and expenses to the date of termination), or continue to
provide any benefit (other than benefits which have accrued pursuant to any plan
or by law) to the Executive under this Agreement.

         E) If the Executive is terminated for performance reasons, the
Executive shall be entitled to certain benefits. The benefits shall consist of
(i) salary continuation at the salary the Executive was receiving at the time of
termination and (ii) the Executive's continued participation in any employee
health and welfare benefit plan to which the Executive was a participant prior
to his termination on the same basis as the Executive had participated as an
employee. The salary continuation and continued participation in any health and
welfare benefit plan shall be for twelve (12) months.

11. Change of Control
    -----------------

     A) "Change in Control" of CuraGen Corporation means the occurrence of any
        -------------------
one of the following events:

          (i) individuals who, on January 1, 2002, constituted 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 January 1, 2002,



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     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, however, that no
     individual elected or nominated as a director of the Company initially as a
     result of an actual or threatened election contest with respect to
     directors or any other actual or threatened solicitation of proxies (or
     consents) by or on behalf of any person other than the Board shall be
     deemed an Incumbent Director;

          (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 Section
     13(d)(3) and 14(d)(2) of the Exchange Act) is or becomes a "beneficial
     owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
     indirectly, of securities of the Company representing 25% 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 the event described in this paragraph (ii) shall
     not be deemed to be a Change in Control by virtue of any of the following
     acquisitions: (A) by the Company or any Subsidiary; (B) by any employee
     benefit plan sponsored or maintained by the Company or Subsidiary; or (C)
     by any underwriter temporarily holding securities pursuant to an offering
     of such securities;



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          (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) more than 50% 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, 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 sponsored or maintained by the
     Surviving Corporation or the Parent Corporation), is or becomes the
     beneficial owner, directly or indirectly, of 20% or more of the total
     voting power of the outstanding voting securities eligible to elect
     directors of the Parent Corporation (or, if there is no Parent Corporation,
     the Surviving Corporation); (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) 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) the stockholders of the Company approve a plan of complete
     liquidation or dissolution of the Company or a sale or disposition of all
     or substantially all of the Company's assets.

     B) 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 25% 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.

12. Benefits Upon Termination

    -------------------------

     A) If the Executive is terminated by the Company for any reason other than
for cause, performance reasons, retirement, total disability or death, or if
this Agreement is not renewed by the Company, pursuant to Section 2.A., the
Executive shall be entitled certain benefits. The benefits shall consist of (i)
salary continuation at the salary the Executive was receiving at the time of
termination and (ii) the Executive's continued participation in any employee
health and welfare benefit plan to which the Executive was a participant prior
to his termination on the same basis as the Executive had participated as an
employee. The salary

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continuation and continued participation in any health and welfare benefit plan
shall be for twelve (12) months.

     B) However, if the Executive is terminated by the Company within twelve
(12) months of a Change of Control as defined in this Agreement, the Executive
shall be entitled to an additional twelve (12) months of salary continuation and
continued participation in any health and welfare benefit plan for a total of
twenty-four (24) months salary continuation and participation in the health and
welfare benefit plan.

     C) If the Executive terminates his employment for a "good reason," the
Executive shall be entitled to the same benefits as provided in paragraph B of
this section. Termination by the Executive of his employment for "good reason"
shall mean termination based on:

          (i) subsequent to a Change in Control of the Company, and without the
     Executive's express written consent, any reduction in Executive's duties or
     responsibilities compared to those prior to a Change in Control, or a
     change in the Executive's reporting responsibilities, titles or offices as
     in effect immediately prior to a Change in Control, or any removal of the
     Executive from, or any failure to re-elect the Executive, to any of his
     previously held positions with the Company; except in connection with the
     termination of the Executive's employment for Cause, Disability or
     Retirement or as a result of the Executive's death or by the Executive
     other than for good reason;

          (ii) subsequent to a Change in Control of the Company, a reduction by
     the Company in the Executive's base salary as in effect on the date hereof
     or as the same may be increased from time to time;

          (iii) subsequent to a Change in Control of the Company, a failure by
     the Company to continue any bonus plans in which the Executive is presently
     entitled



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     to participate (the "Bonus Plans") as the same may be modified from time to
     time but substantially in the form currently in effect, or a failure by the
     Company to continue the Executive as a participant in the Bonus Plans on at
     least the same basis as the Executive presently participates in accordance
     with the Bonus Plans;

          (iv) subsequent to a Change in Control of the Company and without the
     Executive's express written consent, the Company's requiring the Executive
     to be based anywhere other than within fifty (50) miles of the Executive's
     present office location, except for required travel on the Company's
     business to an extent substantially consistent with the Executive's present
     business travel obligations;

          (v) subsequent to a Change in Control of the Company, the failure by
     the Company to continue in effect any benefit or compensation plan, stock
     ownership plan, stock purchase plan, stock option plan, life insurance
     plan, health-and-accident plan or disability plan in which the Executive is
     participating at the time of a Change in Control of the Company (or plans
     providing the Executive with substantially similar benefits), the taking of
     any action by the Company which would adversely affect the Executive's
     participation in or materially reduce the Executive's benefits under any of
     such plans or deprive the Executive of any material fringe benefit enjoyed
     by the Executive at the time of the Change in Control, or the failure by
     the Company to provide the Executive with the number of paid vacation days
     to which the Executive is then entitled in accordance with the Company's
     normal vacation policy in effect on the date hereof; or



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          (vi) subsequent to a Change in Control of the Company, any purported
     termination of the Executive's employment which is not effected pursuant to
     the terms of this Agreement. No such purported termination shall be
     effective.

     D) Upon a Change of Control, notwithstanding any other agreement, all
stock, restricted stock, stock options or restricted stock options of the
Executive shall become fully vested to 100%.

13. Arbitration
    -----------

     A) Any dispute under this Agreement, including any dispute as to cause or
good reason for termination, shall be submitted to binding arbitration subject
to the rules of the American Arbitration Association. EACH OF THE PARTIES
IRREVOCABLY AND UNCONDITIONALLY WAIVES THE RIGHT TO A TRIAL BY JURY IN ANY SUCH
ACTIONS, SUIT OR PROCEEDING. The Company shall bear all costs associated with
the Arbitration, including filing fees and any stipend for the arbitrator. The
Company and the Executive shall each bear its own attorneys' fees. However, if
the Executive prevails in a challenge to the Company's determination for cause,
the Executive shall be entitled to be reimbursed for all attorney fees.

     B) Nothing in this section shall be read to preclude the Company seeking
injunctive relief for the Executive's breach of Section 8, Proprietary and Trade
Secret Information or Section 9, Covenant Not to Compete.



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14. Injunctive Relief
    -----------------

     A) The Executive acknowledges that the services rendered by him under this
Agreement are of a special, unique and extraordinary character and, in
connection with such services, he will have access to confidential information
concerning the Company's business. By reason of this access to confidential
information, the Executive consents and agrees that if he violates any of the
provisions of this Agreement with respect to Proprietary and Trade Secret
Information or the Covenant Not to Compete, the Company would sustain
irreparable harm and, therefore, in addition to any other remedies which the
Company may have under this Agreement or otherwise, the Company shall be
entitled to an injunction to be issued by any court of competent jurisdiction
restraining the Executive from committing or continuing to commit any such
violation of this Agreement.

15. Miscellaneous
    -------------

     A) This Agreement shall be governed by and construed in accordance with the
laws of the State of Connecticut, applicable to agreements made and to be
performed in Connecticut, and shall be construed without regard to any
presumption or other rule requiring construction against the party causing the
Agreement to be drafted.

     B) This Agreement contains a complete statement of all the arrangements
between the Company and the Executive with respect to its subject matter,
supersedes all previous agreements, written or oral, among them relating to its
subject matter and cannot be modified, amended or terminated orally. Amendments
may be made to this Agreement at any time if mutually agreed upon in writing.

     C) Any amendment, notice or other communication under this Agreement shall
be in writing and shall be considered given when received and shall be delivered
personally or mailed



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by Certified Mail, Return Receipt Requested, to the parties at their respective
addresses set forth in this Agreement, or at such other address as a party may
specify by written notice to the other.

     D) The failure of a party to insist upon strict adherence to any term of
this Agreement on any occasion shall not be considered a waiver or deprive that
party of the right thereafter to insist upon strict adherence to that term or
any other term of this Agreement. Any waiver must be in writing.

     E) Each of the parties irrevocably submits to the exclusive jurisdiction of
any court of the State of Connecticut or the Federal District Court of
Connecticut over any action, suit or proceeding relating to or arising out of
this Agreement and the transactions contemplated hereby. Each party hereby
irrevocably waives any objections, including, without limitation, any objection
to the laying of venue or based on the grounds of forum non conveniens which
such party may now or hereafter have to the bringing of any such actions, suit
or proceeding in any such court and irrevocably agrees that process in any such
actions, suit or proceeding may be served upon that party personally or by
Certified or Registered Mail, Return Receipt Requested.

     F) The invalidity or unenforceability of any term or provision of this
Agreement shall not affect the validity or enforceability of the remaining terms
or provisions of this Agreement which shall remain in full force and effect and
any such invalid or unenforceable term or provision shall be given full effect
as is legally permissible. If any term or provision of this Agreement is invalid
or unenforceable in one jurisdiction, it shall not affect the validity or
enforceability of that term or provision in any other jurisdiction.

     G) This Agreement is not assignable by either party except that it shall
inure to the benefit of and be binding upon any successor to the Company by
merger or consolidation or the acquisition of all or substantially all of the
Company's assets, provided such successor assumes



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all of the obligations of the Company, and shall inure to the benefit of the
heirs and legal representatives of the Executive.



By: /s/ Robert E. Patricelli                    4-1-02
    ----------------------------------          ------
    Robert E. Patricelli                         Date
    Chairman, Compensation Committee
    Board of Directors
    CuraGen Corporation
    555 Long Wharf Drive 11th Floor
    New Haven, CT 06511

By: /s/ Jonathan M. Rothberg                    4-1-02
    -------------------------------             ------
    Jonathan M. Rothberg                         Date
    Chief Executive Officer
    CuraGen Corporation
    555 Long Wharf Drive 11th Floor
    New Haven, CT 06511
    ("the Executive")




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                                   SCHEDULE A

     Compensation

     The Executive shall receive the following compensation for services during
the initial term of employment:

                   1) The Executive's base salary shall be $363,700 per year,
                      payable in bi-weekly installments, subject to increases by
                      the Board of Directors, which shall review the salary
                      periodically.

                   2) The Executive, if otherwise eligible, shall participate in
                      any incentive compensation plan, pension, profit sharing,
                      stock purchase or stock option plan, annuity, or group
                      insurance plan, medical plan and other benefits,
                      maintained by the Company for its employees.

                   3) The Executive shall be eligible to receive performance-
                      based bonuses on the attainment of certain goals set by
                      the Compensation Committee of the Board of Directors.

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