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                                                                   Exhibit 10.21

         CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED
         SEPARATELY WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN
         REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.

                DELTASELECT-TM- COLLABORATIVE SERVICES AGREEMENT

         This DeltaSelect-TM- Collaborative Services Agreement, including all
attachments hereto, (this "Agreement") is entered into as of June 27, 2000 (the
"Agreement Date"), by and between DELTAGEN, INC., a Delaware corporation having
a place of business at 1003 Hamilton Avenue, California 94025 ("DELTAGEN"),
GLAXO GROUP LIMITED ("GGL") AND GLAXO RESEARCH AND DEVELOPMENT LIMITED ("GWRD"),
each incorporated in England with a place of business at Glaxo Wellcome House,
Berkeley Avenue, Greenford, Middlesex UB6 ONN, United Kingdom (GGL and GWRD
together with their Affiliates being collectively, "GLAXO").

         WHEREAS, DELTAGEN possesses certain knowledge and experience in the
research, creation, design and generation of Standard Knockout Mice and to
establish a pilot program to create, design and generate Conditional Knockout
Mice and Knock-In Mice; and

         WHEREAS, GLAXO desires to engage DELTAGEN to generate for GLAXO, in
accordance with this Agreement, Standard Knockout Mice and, assuming the pilot
program is successful, Conditional Knockout Mice and Knock-In Mice, and DELTAGEN
desires to undertake such engagement as set forth herein.

         NOW THEREFORE, in consideration of the mutual covenants set forth
below, DELTAGEN and GLAXO (individually "Party" and collectively "Parties")
agree as follows:

1.       DEFINITIONS.

         1.1      "Affiliate" shall mean, with respect to a party to this
Agreement, any entity directly or indirectly controlling or controlled by or in
common control with such party, where "control" is defined as the ownership of
at least *** of the equity or beneficial interests of such entity, or the right
to vote for or appoint a majority of the board of directors or other governing
body of such entity.

         1.2      "Budget" means the pricing and payment terms for a Standard
Knockout Mice Project, Conditional Knockout Mice Project or Knock-In Mice
Project, each as set forth in Attachment I attached hereto.

         1.3      "Conditional Knockout Mouse" or "Conditional Knockout Mice"
means, a mouse or mice generated or provided pursuant to this Agreement in which
***.

         1.4      "Conditional Knockout Mice Project" means a specific project
to create and generate particular Conditional Knockout Mice in accordance with
the terms of a specific Scope of Work under this Agreement.

         1.5      "Confidential Information" means the content of this
Agreement, the DELTAGEN Technology, the Data, the GLAXO Technology, the Study
Materials, and, with respect to a party, all data and/or information of any kind
whatsoever (including without limitation, data, databases, compilations,
formulae, schemata, models, patent disclosures, procedures, processes,
projections, protocols, results of experimentation and testing,

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

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specifications, strategies and techniques), and all tangible and intangible
embodiments thereof of any kind whatsoever (including without limitation,
apparatus, compositions, documents, drawings, machinery, patent applications,
records, laboratory and research notebooks, memoranda and reports), which are
disclosed by such party to the other party and is marked, identified as or
otherwise acknowledged to be confidential at the time of disclosure to the other
party.

         1.6      "*** Mouse" or "*** Mice" means a mouse or mice that have been
engineered, ***.

         1.7      "Data" means all data or information generated under a Project
under this Agreement, including but not limited to all information, records,
reports and other material(s) required to be generated, collected or analyzed by
DELTAGEN thereunder.

         1.8      "DELTAGEN Technology" means all Inventions owned by or
licensed to DELTAGEN related to ***.

         1.9      "Effective Commencement Date" means the commencement date for
a particular Project, either as specified in this Agreement or, if different, as
specified in the applicable Scope of Work.

         1.10     "*** Mouse" or "*** Mice" means a mouse or mice that contain
one or more regions of DNA that have been engineered ***.

         1.11     "GLAXO Representative" means the representative identified in
writing by GLAXO to DELTAGEN on a Scope of Work, as such representative may be
changed from time to time in writing by GLAXO.

         1.12     "GLAXO Technology" means all Inventions and *** owned by or
licensed to GLAXO ***.

         1.13     "Inventions" means technology, information, data, know-how,
inventions, improvements and all patent, copyright, trade secret, and other
intellectual property rights therein and thereto.

         1.14     "Knock-In Mice" means, ***; mice or a mouse generated pursuant
to this Agreement that ***.

         1.15     "Knock-In Mice Project" means a specific project to create and
generate Knock-In Mice in accordance with the terms of a specific Scope of Work
under this Agreement.

         1.16     "Milestone" means the milestones set forth on the Scope of
Work attached hereto.

         1.17     "Project" means a Standard Knockout Mice Project, Conditional
Knockout Mice Project or Knock-In Mice Project, as the context requires.

         1.18     "Project Mice" means, with respect to a particular Project,
the specific mouse or mice that are generated in the performance of such Project
(i.e., the particular animals

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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themselves); Project Mice may be Standard Knockout Mice, Conditional Knockout
Mice or Knock-In Mice, depending on the Project.

         1.19     "Scope of Work" means the mutually agreed, applicable written
work plan for a Project, substantially in the form attached hereto as Attachment
I and more particularly as Section IA of Attachment I (Standard Knockout Mice
Project), Section IB of Attachment I (Conditional Knockout Mice Project) and
Section IC of Attachment I (Knock-In Mice Project).

         1.20     "Standard Knockout Mouse" or "Standard Knockout Mice" ***,
mice or a mouse generated pursuant to this Agreement that have ***.

         1.21     "Standard Knockout Mice Project" means a specific project to
create and generate Standard Knockout Mice in accordance with the terms of a
specific Scope of Work under this Agreement.

         1.22     "Standard Mutation" means the interruption, disruption or
deletion in a portion of a specified gene.

         1.23     "Study Materials" means any samples or materials (including
chemical or biological) provided by GLAXO to DELTAGEN for purposes of a Project
under this Agreement.

2.       PROJECTS

         2.1      INDIVIDUAL PROJECTS. If GLAXO wishes to have DELTAGEN perform
a Project under this Agreement, GLAXO shall initiate each such request for a
Scope of Work by notifying DELTAGEN in writing in the form set forth in
Attachment II and providing a description of the particular Project requested as
well as the information set forth in Section 2.2 and the Scope of Work. DELTAGEN
shall evaluate each such request to determine whether such Project is feasible,
if DELTAGEN requires technical or scientific modifications or if DELTAGEN
requires additional information to undertake such evaluation. If such Project in
DELTAGEN's reasonable discretion is commercially or technically infeasible,
DELTAGEN shall have the right (without penalty) to decline to undertake such
Project. The terms of this Agreement, together with the applicable Scope of Work
and the Budget, shall form the entire agreement of the Parties with respect to
each particular Project.

         2.2      INITIATION OF PROJECTS. Prior to DELTAGEN's initiation of each
Project, GLAXO shall:

                  2.2.1    Identify to DELTAGEN in writing each Project to be
initiated and agree in writing with DELTAGEN upon the Scope of Work for such
Project;

                  2.2.2    GLAXO shall be solely responsible for providing to
DELTAGEN the data and information *** and other information for such Project.

                  2.2.3    Consult with and agree in writing with DELTAGEN
regarding any proposed modifications or additions to the form of Scope of Work
attached as Attachment I for such Project.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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                  2.2.4    Provide in writing to DELTAGEN *** and other
information, materials and data reasonably required by DELTAGEN to undertake
such Project (including the Starting Materials specified in Attachment I).

                  2.2.5    Transfer to DELTAGEN, to the extent possible and
under appropriate license if applicable, *** and other GLAXO Technology
licensed, owned by or otherwise available to GLAXO for use solely by DELTAGEN
and its subcontractors (see Section 10) and solely on the Project, that may be
suitable ***.

         2.3      COMMENCEMENT OF PROJECT WORK. Unless otherwise specified in
its Scope of Work, each Project conducted hereunder shall commence *** after
written agreement by both parties on a Scope of Work and DELTAGEN's receipt from
GLAXO of all information and materials set forth in Section 2.2 above relating
to such Project .

         2.4      PERFORMANCE. DELTAGEN shall use commercially reasonable
efforts to perform its obligations under this Agreement, PROVIDED THAT, GLAXO
acknowledges and agrees that the performance of the Projects involves a number
of technologically complex steps and that any time periods for performance and
the Scope of Work may be subject to change due to potential technological
difficulties encountered. DELTAGEN shall notify GLAXO of technical difficulties
as soon as reasonably practicable after such difficulties are encountered and
the parties shall discuss and agree in good faith upon methods to resolve such
technical difficulties in a reasonable manner.

         2.5      COMPLETION OF PROJECT. Each Project shall be deemed complete
upon GLAXO's receipt of the Data for such Project under Section 9 below *** set
forth in the Scope of Work for such Project, unless GLAXO and DELTAGEN mutually
agree otherwise.

         2.6      ADHERENCE TO SCOPE OF WORK. DELTAGEN shall perform those
activities described in the Scope of Work for each Project. Neither Party shall
change or deviate from a Scope of Work in any material manner or degree without
the prior written consent of the other Party.

         2.7      CHANGES TO A PROJECT. GLAXO shall have the right, from time to
time, to propose modifications to the Scope of Work of a Project. If GLAXO
proposes to change any terms of a Project, including but not limited to the
estimated time schedule for such Project, GLAXO shall submit such
modification(s) in writing to DELTAGEN (the "Proposed Modification"). Such
Proposed Modification shall be implemented by the Parties upon the written
agreement of both parties to such Proposed Modification (which agreement shall
not be unreasonably withheld) and a revised Budget and time schedule for such
Proposed Modification. DELTAGEN shall have the right, in its commercially
reasonable discretion, to accept or reject such Proposed Modification based upon
DELTAGEN's good faith reasonable belief as to whether such proposed
modifications would alter DELTAGEN's technical, performance or financial
obligations under a Scope of Work.

         2.8      STANDARDS OF WORK AND ANIMAL CARE. With respect to each
Project, DELTAGEN shall comply with:- (a) all applicable IACUC standards and
good industry standards regarding the maintenance and care of the Standard
Knockout Mice, Conditional Knockout Mice or Knock-In Mice involved in a
particular Project; (b) laboratory animal care and welfare as

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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reasonably implemented by Deltagen in its facilities and operations; (c) to the
extent applicable, all other local, state and federal laws, rules, regulations,
and ordinances including, but not limited to, the federal Food, Drug and
Cosmetic Act (21 U.S.C. 301 et seq.); FDA regulations including, but not limited
to, Good Laboratory Practices (21 C.F.R. Part 58) and Good Manufacturing
Practices (21 C.F.R. Parts 210 and 211); and the federal Animal Welfare Act (7
U.S.C. 2131 et seq.), and the regulations of the United States Department of
Agriculture. DELTAGEN shall replace any Project Mice that arrive at GLAXO
diseased or dead except for disease or death (i) directly or indirectly caused
by or resulting from any infirmity, susceptibility, condition or other factor
induced or inherent in such Project Mice as a result of, or otherwise caused by
or a consequence of, the Project and/or (ii) resulting from the actions of
GLAXO's designated carrier or GLAXO itself. Upon the request of GLAXO, DELTAGEN
shall promptly provide a written report to GLAXO concerning DELTAGEN's
maintenance and care of the Standard Knockout Mice, Conditional Knockout Mice or
Knock-In Mice involved in a particular Project.

         2.9      CONDITIONAL KNOCKOUT MICE AND KNOCK-IN MICE. Notwithstanding
anything to the contrary contained in this Agreement, GLAXO acknowledges and
agrees that all Projects involving *** are undertaken ***. The Milestones
associated with the implementation of a pilot project to produce Conditional
Knockout Mice or Knock-In Mice will be set forth in the applicable Scope of
Work.

3.       PAYMENTS AND BUDGET.

         3.1      BUDGET. GLAXO shall pay to DELTAGEN the payments set forth in
the Budget for each Project. Except as set forth in a revised Budget under
Section 3.2 below, such payments shall constitute full payment for such Project,
including all labor, materials and overhead and GLAXO shall have no other
payment obligations hereunder.

         3.2      PAYMENTS. DELTAGEN shall submit invoices to GLAXO for the
payments set forth in the Scope of Work and Budget separately for each Project,
upon DELTAGEN's completion of each Milestone set forth in the Scope of Work and
Budget for that Project. GLAXO shall pay all DELTAGEN's invoices at the end of
the month after the month in which such invoice is received. DELTAGEN shall
include with each invoice a written statement of DELTAGEN's completion of all
Milestones for which payment is being sought. Upon request, DELTAGEN will
provide reasonable supporting documentation, to the extent available,
demonstrating or substantiating such completion.

         3.3      MAXIMUM OBLIGATION. In no event shall DELTAGEN be obligated to
provide services or to undertake any Projects that would cause the aggregate
amount payable under this Agreement for all Projects, ***, to exceed ***.

         3.4      PAYMENT WITHOUT DEDUCTION. All payments due under this
Agreement will be made in full without deduction for or on account of any
present or future taxes or duties of whatever nature that may be imposed, except
as provided in Section 3.5.

         3.5      WITHHOLDING TAXES. Glaxo *** from amounts otherwise due
hereunder if and as compelled by applicable law and shall remit the amount
withheld to the appropriate taxing authorities on Deltagen's behalf and the
remainder to Deltagen. Glaxo will provide Deltagen with a written receipt or
a tax deduction certificate from the tax authority for all taxes so withheld.
GLAXO will cooperate with DELTAGEN in obtaining exemption from such
withholding and in minimizing or avoiding any such tax withholding
requirement, as available under applicable law.

         3.6      CURRENCY. All amounts due

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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under this Agreement are payable in US Dollars.

4.       RIGHTS TO INVENTIONS.

         4.1      DELTAGEN'S INVENTIONS. DELTAGEN shall own all DELTAGEN
Technology.

         4.2      GLAXO'S INVENTIONS. GLAXO shall own all GLAXO Technology.

         4.3      PROJECT MICE OWNERSHIP. With respect to each Project under
this Agreement, after GLAXO has made to DELTAGEN all payments associated with
Milestones that have arisen and been completed by DELTAGEN and all other
payments due under this Agreement for such Project, GLAXO shall own (i) all
Project Mice generated under such Project, and any sperm, tissues, embryonic
stem cells or other cells, materials or progeny derived or generated by DELTAGEN
or its subcontractors from those particular animals in the course of performing
such Project and (ii) all phenotypic data and information with respect to the
Project Mice generated under such Project (without which, ownership for all
items not paid for by GLAXO shall remain with DELTAGEN), in each case subject to
the following:

                  4.3.     Notwithstanding GLAXO's ownership of the specified
items pursuant to Article 4.3, DELTAGEN shall continue to own all of the
DELTAGEN Technology applicable thereto, inherent therein or embodied thereby.

                  4.3.2    Conditioned on payment in full of all amounts due as
described above, DELTAGEN grants GLAXO a non-exclusive license under the
DELTAGEN Technology to use such Project Mice, phenotypic data and information
derived therefrom, and tissues, cells, materials or progeny, for internal
research only and not for any other use or purpose. Otherwise, GLAXO's ownership
of such Project Mice and phenotypic data and information derived therefrom, and
related tissues, cells, materials or progeny, shall not include or imply any
grant of any express or implied license under any DELTAGEN Technology
(including, without limitation, any right or license to commercialize) For the
avoidance of doubt, nothing contained in this Section 4.3.2. shall constrain in
any way GLAXO's right to commercialize as it sees fit the results of any of its
research on Project Mice or results derived from its use of DELTAGEN Technology
so long as such commercialization or related activities do not infringe or
misappropriate of any of DELTAGEN's intellectual property or other proprietary
rights, do not make or constitute any unauthorized or unlicensed use of the
DELTAGEN Technology, and do not make unauthorized use or disclosure of any of
DELTAGEN's Confidential Information.

                  4.3.3    Except as expressly set forth in the applicable Scope
of Work, DELTAGEN shall not transfer to a third party any Project Mice (except
***) generated by DELTAGEN for GLAXO under this Agreement.

                  4.3.4    GLAXO acknowledges and agrees that, subject to
Section 4.3.5, (a) DELTAGEN may at any time (past, present or future),
independently or with or for others, research, develop and/or commercialize
the *** provided by GLAXO to DELTAGEN under this Agreement; (b) DELTAGEN may
at any time (past, present or future), independently or with or for others,
research, develop and/or commercialize any other mice that are derived from
DELTAGEN's work for GLAXO under the Project but not the Project Mice, either
for DELTAGEN's own products and programs or for a third party; and (c)

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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DELTAGEN or a third party may at any time, independently (or with others) have
secured, own or be seeking patent or other intellectual property rights with
respect to, or with respect to the use of any other mice that are derived from
DELTAGEN's work for GLAXO under the Project but not the Project Mice.

                  4.3.5    Notwithstanding anything to the contrary in this
Agreement, GLAXO shall not use the Project Mice or any Data, results or other
information provided by DELTAGEN to GLAXO to reverse-engineer or practice (and
GLAXO shall not directly or indirectly acquire rights to) any of the DELTAGEN
Technology or any of DELTAGEN's or any of its licensor's methods, processes,
techniques, inventions, know-how or intellectual property rights relating
directly or indirectly to the design, creation, development, generation or
production of Standard Knockout Mice, Conditional Knockout Mice, Knock-In Mice
or transgenic animals.

         4.4      DELTAGEN'S USE OF GENE SEQUENCES ON A BLINDED BASIS. Except
where technically infeasible or the applicable Scope of Work provides otherwise,
DELTAGEN shall perform all Projects under this Agreement on a "blinded" basis,
meaning that (a) DELTAGEN shall not use the gene sequence information provided
by GLAXO to DELTAGEN to determine the identity of such genes, to blast such gene
sequences against gene sequences of DELTAGEN or a third party or to generate
Project Mice for DELTAGEN or a third party; (b) the gene sequence information
provided by GLAXO shall be used by DELTAGEN solely for the purpose of
undertaking and performing Projects under this Agreement and (c) DELTAGEN shall
not use or disclose such gene sequence information to any third party other than
as allowed by the applicable Scope of Work or as reasonably required in the
performance of its obligations under the Project or pursuant to this Agreement;
PROVIDED, HOWEVER, that this Section 4.4 shall not limit the use or disclosure
by DELTAGEN of the same or similar information when independently generated or
obtained from other sources or the independent generation by DELTAGEN of the
same or similar mice without reference to the gene sequence information provided
by GLAXO and so long as such use or disclosure does not infringe or
misappropriate of any of GLAXO's intellectual property or other proprietary
rights, do not make or constitute any unauthorized or unlicensed use of the
GLAXO Technology, and do not make unauthorized use or disclosure of any of
GLAXO's Confidential Information. In addition to any other remedies available to
GLAXO at Law, equity or under this Agreement, any breach of this Section 4.4 by
DELTAGEN that is not willful or intentional shall constitute a basis for
termination by GLAXO of this Agreement but not any other agreement between
DELTAGEN and GLAXO, subject to DELTAGEN's applicable rights of notice and
opportunity to cure. Any willful or intentional breach of this Section 4.4 by
Deltagen shall constitute the basis for termination by Glaxo of this Agreement
and of any other Agreement between Deltagen and Glaxo, subject to DELTAGEN's
applicable rights of notice and opportunity to cure. In the event of either such
termination GLAXO shall be entitled, upon payment to DELTAGEN of all amounts due
hereunder, to continue to use all (i) all Project Mice generated up to the date
of termination, and any sperm, tissues, embryonic stem cells or other cells,
materials or progeny derived or generated by DELTAGEN or its subcontractors from
those particular animals in the course of performing such Project, and (ii) all
phenotypic data and information with respect to the Project Mice, in each case
subject to Sections 4.3.1 through 4.3.6.

         4.5      NO OTHER TECHNOLOGY RIGHTS OR LICENSES. No Party shall, as a
result of this Agreement, obtain any ownership interest, license or other right
(whether express or

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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implied, including without limitation licenses or other rights with respect to
any patent or other intellectual property rights owned by or licensed to the
other Party or a third party (whether to Project Mice and/or any sperm, tissues,
embryonic stem cells or other cells, materials or progeny derived or generated
therefrom, or otherwise)) in any technology, Confidential Information or other
data or information, know-how, patents, pending patent applications, products,
programs, materials or intellectual property rights of the other Party,
including items owned, controlled or developed by such other Party or
transferred by such other Party pursuant to this Agreement.

5.       CONFIDENTIALITY.

         5.1      CONFIDENTIAL INFORMATION. Except as otherwise expressly
provided in this Agreement, for a period of ten (10) years from the later of the
date of disclosure or the date of termination of this Agreement, (a) each Party
shall maintain in confidence the Confidential Information of the other Party;
(b) neither Party shall use, disclose or grant the use of the other's
Confidential Information, except on a "need-to-know" basis to those directors,
officers, employees, and agents to the extent such disclosure is reasonably
necessary in connection with its activities as expressly authorized by this
Agreement and (c) to the extent that disclosure is authorized by this Agreement,
prior to such disclosure, the Party wishing to disclose the other Party's
Confidential Information shall obtain the written agreement of any such person
who is not otherwise bound by confidentiality obligations at least as
restrictive as the obligations set forth in this Agreement, to hold in
confidence and not make use of the Confidential Information for any purpose
other than those permitted by this Agreement.

         5.2      PERMITTED DISCLOSURES. The nonuse and nondisclosure
obligations contained in this Article 5 shall not apply to data and/or
information which the other party can establish by written documentation (a) to
have been publicly known prior to disclosure of such data and/or information by
the disclosing party to the other party, (b) to have become publicly known,
without fault on the part of the other party, subsequent to disclosure of such
data and/or information by the disclosing party to the other party, (c) to have
been received by the other party at any time from a source, other than the
disclosing party, rightfully having possession of and a right to disclose such
data and/or information, (d) to have been otherwise known by the other party
prior to disclosure of such data and/or information by the disclosing party to
the other party, or (e) to have been independently developed by the employees or
agents of the other party without access to or the use of such data and/or
information disclosed by the disclosing party to the other party.

         5.3      TERMS OF THIS AGREEMENT. Neither Party shall disclose any
terms or conditions of this Agreement (including without limitation the Budget)
to any third party without the prior consent of the other Party, except as
required by applicable law; PROVIDED HOWEVER, that either Party may disclose the
terms or conditions of this Agreement to a third party under an obligation of
confidentiality to such Party in connection with a proposed sale or in the event
of a proposed merger, change in control, consolidation, an equity investment by
such third party in such Party or other similar transaction. Notwithstanding the
foregoing, GLAXO and DELTAGEN shall agree upon the substance of information that
can be used to describe the existence and/or terms of this transaction in a
press release and GLAXO and DELTAGEN shall have the right to disclose such
information, as such information may be modified by mutual agreement of the

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WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
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parties from time to time.

         5.4      RETURN OF CONFIDENTIAL INFORMATION. Except as expressly
provided in this Agreement or in a particular Scope of Work, nothing herein
shall be construed as giving either Party any license, right, title or interest
in or ownership of the other Party's Confidential Information, whether express
or implied. Upon termination of this Agreement or a particular Project as
provided in Article 11, a Party shall return all Confidential Information of the
other Party and/or destroy any portion of any documents, computer records, notes
and other material retained by such Party containing the Confidential
Information of the other Party. However, each Party may retain one copy of such
Confidential Information in its legal files to be used only for interpretation
of and compliance with this Agreement.

6.       REPRESENTATIONS AND WARRANTIES.

         6.1      MUTUAL REPRESENTATIONS AND WARRANTIES. Subject to the other
provisions of this Article 6, each Party hereby represents and warrants to the
other Party as follows:

                  6.1.1    Such Party is a corporation duly organized, validly
existing and in good standing under the laws of the state in which it is
incorporated.

                  6.1.2    Such Party (a) has the corporate power and authority
and the legal right to enter into this Agreement and to perform its obligations
hereunder, and (b) has taken all necessary corporate action on its part to
authorize the execution and delivery of this Agreement and the performance of
its obligations hereunder. This Agreement has been duly executed and delivered
on behalf of such Party, and constitutes a legal, valid, binding obligation,
enforceable against such Party in accordance with its terms.

                  6.1.3    All necessary consents, approvals and authorizations
of all governmental authorities and other persons required to be obtained by
such Party in connection with this Agreement have been obtained.

                  6.1.4    The execution and delivery of this Agreement and the
performance of such Party's obligations hereunder (a) do not conflict with or
violate any requirement of applicable laws or regulations, and (b) do not
conflict with, result in a breach of any of the terms and provisions of, or
constitute a default under, any contractual obligation of it, and (c) do not
conflict with or result in a breach of any of the terms and provisions of its
charter or operative documents or bylaws.

                  6.1.5    Such Party shall comply with all applicable material
laws and regulations related to its activities contemplated under this
Agreement.

         6.2      DELTAGEN TECHNOLOGY. DELTAGEN represents and warrants to its
best knowledge (using reasonable diligence) that DELTAGEN (a) is the owner or
licensee of the DELTAGEN Technology and (b) has the right to use the DELTAGEN
Technology to generate Standard Knockout Mice, Conditional Knockout Mice and
Knock-In Mice.

         6.3      GLAXO TECHNOLOGY. GLAXO represents and warrants that (a) to
its best knowledge (using reasonable diligence) it is the owner or licensee of
the GLAXO Technology and (b) it has the right to provide the gene sequences and
information relating thereto to DELTAGEN and to have made Standard Knockout
Mice, Conditional Knockout Mice and Knock-In Mice under this Agreement.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
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         6.4      LIMITATION OF WARRANTY AND LIABILITY. EXCEPT AS OTHERWISE
EXPRESSLY SET FORTH IN THIS AGREEMENT, DELTAGEN MAKES NO WARRANTIES, EXPRESS OR
IMPLIED, WITH RESPECT TO THE STANDARD KNOCKOUT MICE, CONDITIONAL KNOCKOUT MICE,
KNOCK-IN MICE OR DATA GENERATED UNDER THIS AGREEMENT OR THE PROJECTS AND
DELTAGEN DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT
LIMITATION IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR LOSS OF
PROFITS OR INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES DIRECTLY OR INDIRECTLY
ARISING OUT OF THIS AGREEMENT OR THE RESEARCH, DEVELOPMENT, GENERATION OR USE OF
THE STANDARD KNOCKOUT MICE, CONDITIONAL KNOCKOUT MICE, KNOCK-IN MICE OR DATA
GENERATED UNDER THIS AGREEMENT. Except as specifically provided in Section 2.8,
all Standard Knockout Mice, Conditional Knockout Mice and Knock-In Mice
generated pursuant to this Agreement are delivered to and will be accepted by
GLAXO on an "as-is" basis and without any warranty, express or implied.

         6.5      RESPONSIBILITY FOR SELECTION OF GENE SEQUENCE AND RESULTING
STANDARD KNOCKOUT MICE, CONDITIONAL KNOCKOUT MICE OR KNOCK-IN MICE.
Notwithstanding anything to the contrary in this Agreement, GLAXO acknowledges
and agrees that (a) each gene sequence (or portion thereof) that is the subject
of a Project is solely selected by GLAXO and GLAXO shall be solely responsible
for selecting and providing DELTAGEN with such specific gene sequences for each
Project. Consequently, GLAXO shall solely bear the risk for any Claims (defined
in Section 12.1 below) relating to *** Standard Knockout Mice, Conditional
Knockout Mice or Knock-In Mice generated under this Agreement and (b) DELTAGEN's
representations and warranties under this Article 6 shall not apply or relate to
the identification, selection or use of the specific gene sequences for any
Project under this Agreement or any Standard Knockout Mice, Conditional Knockout
Mice, Knock-In Mice or Data arising from the deletion, interruption or
disruption of such gene sequences .

7.       REPORTING. Unless another method of reporting is specified in the
applicable Scope of Work, DELTAGEN shall deliver via overnight delivery service
(or other reasonable means agreed to by the parties) to the GLAXO Representative
all reports required to be delivered in connection with a Project.

8.       RECORD RETENTION, INSPECTIONS AND COOPERATION.

         8.1      RETENTION BY DELTAGEN. At GLAXO'S request, DELTAGEN shall
maintain all written Data and reports from each Project for a period of one (1)
year from the date of completion of such Project. At the expiration of such one
(1) year period, GLAXO, at GLAXO's cost and expense, shall arrange with DELTAGEN
for delivery of such Data to GLAXO or DELTAGEN may dispose of such written Data
sixty (60) days after providing written notice of the same to GLAXO.

         8.2      GOVERNMENTAL AUDITS. If a federal, state or local government
authority conducts or gives notice of its intent to conduct an inspection or
takes regulatory action with respect to a Project conducted under this
Agreement, the Party learning thereof shall reasonably notify in writing the
other Party thereof and each Party shall provide the other with any information

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       10
<PAGE>

reasonably required in connection therewith.

9.       DATA. Notwithstanding the provisions of Section 8, for each Project,
DELTAGEN shall prepare and submit to GLAXO or its designee the Data set forth
under the applicable Scope of Work with respect to a particular Project within
forty-five (45) days after (i) the date of termination or completion of the
Milestones on the Scope of Work for such Project or, if later, (ii) the date
GLAXO requests for delivery of such Data.

10.      SUBCONTRACTING AND INDEPENDENT CONTRACTOR.

         10.1     SUBCONTRACTING. GLAXO is aware that certain Projects may
require DELTAGEN to subcontract to third parties portions of the work required
under a Scope of Work. GLAXO shall be deemed to have approved such
subcontracting on the following terms and conditions: (i) DELTAGEN shall not be
allowed or authorized to make any representations relating to GLAXO without the
prior written consent of GLAXO; and (ii) such third party subcontractor shall be
subject to the terms and conditions of this Agreement. Prior to subcontracting
any work contemplated by a Project, DELTAGEN shall notify GLAXO of the intended
third party subcontractor and ***, DELTAGEN may subcontract such work under the
Scope of Work to such third party subcontractor. If GLAXO does object to the use
of a particular subcontractor, in its sole discretion, DELTAGEN shall be
prohibited from using such subcontractor to perform work under this Agreement
and DELTAGEN may terminate the affected Project(s) without penalty if DELTAGEN
determines in its reasonable discretion that its ability to timely complete the
Project(s) within Budget is materially and adversely affected by such
prohibition.

         10.2     INDEPENDENT CONTRACTOR. DELTAGEN shall perform its obligations
under this Agreement as an independent contractor and nothing contained herein
shall be construed to be inconsistent with that relationship or status. Neither
Party, nor their officers, directors, employees or agents shall be considered
employees or agents of the other Party and shall not be entitled to participate
in any of the other Party's benefit plans, programs, employment policies, or
workers' compensation insurance. This Agreement shall not constitute, create, or
in any way be interpreted as a joint venture, partnership or business
organization of any kind. Neither Party shall have the authority to bind the
other Party to any agreement whatsoever.

11.      TERM AND TERMINATION.

         11.1     TERM. This Agreement shall commence on the Agreement Date and
remain in full force and effect, unless earlier terminated as provided below in
this Article 11, until the latest of (a) two (2) years after the Agreement Date,
(b) the completion by DELTAGEN of all Milestones under any Projects commenced
under this Agreement, or ***, unless otherwise agreed between the Parties.

         11.2     TERMINATION BY GLAXO. GLAXO shall have the right to terminate
this Agreement or a Project at any time without cause, upon *** prior written
notice.

         11.3     TERMINATION BY DELTAGEN. DELTAGEN shall have the right to
terminate any Project upon DELTAGEN's identification of an item or
circumstance under Section 2.4 or 10.1 that would prevent DELTAGEN from
completing such Project using commercially reasonable efforts by providing
*** written notice to GLAXO, which notice shall contain

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       11
<PAGE>

the basis for such termination.

         11.4     TERMINATION BY EITHER PARTY.

                  11.4.1   Except as otherwise provide in Article 14 below, this
Agreement or a Project may be terminated by either Party upon any material
breach of this Agreement by the other Party, provided that any breaching Party
shall be given not less than sixty (60) days (fifteen (15) days, in the case of
payment defaults) prior written notice of such breach and the opportunity to
cure such breach during such period.

                  11.4.2   This Agreement or a Project may be immediately
terminated by either Party if the other Party is dissolved or liquidated, files
or has filed against it a petition in bankruptcy or has a receiver appointed for
a substantial part of its assets.

         11.5     RIGHTS AND OBLIGATIONS AFTER NOTICE OF TERMINATION.

                  11.5.1   If this Agreement is terminated either by GLAXO
pursuant to Section 11.2 or by DELTAGEN pursuant to Section 11.4, then DELTAGEN
shall cease further work on all Projects. If a Project is terminated by GLAXO
pursuant to Section 11.2, then DELTAGEN shall cease further work on the
terminated Project and shall have the right to cease further work on any or all
other Projects.

                  11.5.2   If a Project is terminated by DELTAGEN pursuant to
Section 11.3, then DELTAGEN shall cease further work on the terminated Project.
If this Agreement is terminated by GLAXO pursuant to Section 11.4, then DELTAGEN
shall cease further work on all Projects.

                  11.5.3   In the event of any termination of this Agreement or
a Project, then with respect to the affected Project(s):

                           11.5.3.1 DELTAGEN may endeavor to cancel, if
permitted under the terms of applicable agreements, any third party obligations
that relate thereto.

                           11.5.3.2 Within *** after DELTAGEN's cessation of
work thereon, DELTAGEN shall provide GLAXO with a written statement of all work
performed by it through termination, including any non-cancelable costs or
expenses incurred by DELTAGEN prior to termination. Subject to the next
sentence, (i) DELTAGEN shall invoice GLAXO for all Milestones completed by
DELTAGEN and for all reasonable non-cancelable costs or expenses and (ii) if
such notice is received by DELTAGEN after work has commenced but prior to
DELTAGEN's completion of work under a Milestone, DELTAGEN shall invoice GLAXO
for payment of such uncompleted Milestone as if DELTAGEN had completed such
Milestone and GLAXO shall pay DELTAGEN for such uncompleted Milestone. ***,
however, *** to the work performed and/or Milestones completed that constitute
such breach by DELTAGEN and ***.

                           11.5.3.2 Within sixty (60) days of DELTAGEN'S or
GLAXO's notice of termination, as the case may be, DELTAGEN shall deliver to
GLAXO all unused Study

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       12
<PAGE>

Materials and GLAXO Technology generated under such Project.

                           11.5.3.3 Within thirty (30) days after payment to
DELTAGEN of all amounts due hereunder, DELTAGEN shall deliver to GLAXO (i) all
Project Mice generated under such Project up to the date of termination, *** or
generated by DELTAGEN or its subcontractors from those particular animals in the
course of performing such Project, and (ii) all phenotypic data and information
with respect to the Project Mice, in each case subject to Sections 4.3.1 through
4.3.

         11.6     EFFECT OF EXPIRATION OR TERMINATION. Expiration or termination
of this Agreement shall not relieve the parties of any obligation accruing prior
to such expiration or termination. The provisions of Sections 6.4, 6.5, and 11.5
and Articles 1, 3 (with respect to periods prior to termination), 4, 5, 7, 8, 12
and 16 shall survive any expiration or termination of this Agreement.

12.      INDEMNIFICATION.

         12.1     GLAXO'S INDEMNIFICATION. GLAXO shall defend, indemnify and
hold harmless DELTAGEN and its directors, officers, employees and agents from
and against any and all losses, liabilities, damages or expenses (collectively,
"Liabilities") that they may suffer as a result of any claims, demands, actions
or other proceedings (collectively, "Claims") made or instituted by any third
party and arising out of or relating to (a) a breach of any representation,
warranty or covenant of GLAXO under this Agreement or (b) GLAXO's gross
negligence or willful misconduct, except in each case to the extent such
Liabilities resulted from the gross negligence or willful misconduct of
DELTAGEN.

         12.2     DELTAGEN'S INDEMNIFICATION. DELTAGEN shall defend, indemnify
and hold harmless GLAXO and its directors, officers, employees and agents from
and against any and all Liabilities that they may suffer as a result of any
Claims made or instituted by any third party and arising out of or relating to
(a) a breach of any representation, warranty or covenant of DELTAGEN under this
Agreement or (b) DELTAGEN's gross negligence or willful misconduct, except in
each case to the extent such Liabilities resulted from the gross negligence or
willful misconduct of GLAXO.

         12.3     PROCEDURE. A Party (the "Indemnified Party") which intends to
claim indemnification under this Article 12, shall promptly notify the other
Party (the "Indemnifying Party") of any Claim with respect to which the
Indemnified Party intends to claim such indemnification. The Indemnifying Party
shall have the right to assume the defense of such Claim with counsel selected
by the Indemnifying Party; PROVIDED, HOWEVER, that the Indemnified Party shall
have the right to retain its own counsel and the fees and expenses shall be paid
by the Indemnifying Party only if representation of the Indemnified Party by the
counsel retained by the Indemnifying Party would be inappropriate due to actual
or potential differing interests between the Indemnified Party and any other
party represented by such counsel in such proceedings. The indemnity obligations
under this Article 12 shall not apply to amounts paid in settlement of any
Liability if such settlement is effected without the consent of the Indemnifying
Party, which consent shall not be withheld unreasonably. The failure of the
Indemnified Party to promptly notify the Indemnifying Party of a potential Claim
shall not constitute a waiver of, or result in the loss of, such Party's right
to indemnification under this Section 12.3, except to the extent that the

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       13
<PAGE>

Indemnifying Party's rights and/or its ability to defend such Claim is
prejudiced by the Indemnified Party's failure to notify the Indemnifying Party
of such Claim within a reasonable time after the commencement of any action. The
Indemnifying Party may not settle the action or otherwise consent to an adverse
judgment in such action that diminishes the rights or interests of the
Indemnified Party without the express written consent of the Indemnified Party,
which consent shall not be withheld unreasonably. The Indemnified Party, its
employees and agents, shall cooperate fully with the Indemnified Party and its
legal representatives in the investigation of any Claim covered by this
indemnification.

13.      TRADEMARKS AND PUBLICITY. Except as set forth in Section 5.3 above,
each Party agrees not to identify the other Party or any Affiliate of the other
Party in any promotion advertising or other promotion materials to be
disseminated to the public, or to use any trademark, service mark, trade name or
symbol of the other Party or any Affiliate of the other Party without the
express written consent of the other Party.

14.     DELAYS OR FORCE MAJEURE.

         14.1     FORCE MAJEURE. Neither Party shall be liable for the failure
or delay to perform its obligations under this Agreement or a Project if such
failure or delay is caused by or results from causes beyond such Party's
reasonable control, including but not limited to strikes or other labor
disturbances, embargoes, acts of God, omissions or delays in acting by any
governmental authority or the other party, lockouts, riots, wars, fires, floods,
earthquakes or storms. A Party claiming a right to excused performance under
this Section 14.1 shall immediately notify the other Party in writing of the
extent of its inability to perform, which notice shall specify the occurrence
beyond its reasonable control that prevents such performance, and such Party
shall exert reasonable efforts to eliminate, cure and overcome any such causes
and to promptly resume performance of its obligations under this Agreement.

         14.2     DELAY. If GLAXO delays in performing its obligations under a
Project for any reason, the estimated date that DELTAGEN is targeted to complete
its duties and obligations as described in the applicable Scope of Work shall be
extended by the period of time corresponding to the delay provided always that
DELTAGEN gives GLAXO reasonable notice of the reason for the delay.

15.      NOTICES. Any notice required or permitted to be given hereunder by one
of the parties hereto to the other party shall be in writing and delivered by
any lawful means to the address of the other party set forth below or at such
other address as either Party hereto may designate in writing. If sent by
facsimile letter, notice shall be deemed given when the transmission is
completed if the sender has a confirmed transmission report. Any notice sent by
facsimile must also be sent by mail or overnight courier or delivered by hand.

IF TO DELTAGEN:

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       14
<PAGE>

Deltagen, Inc.
1003 Hamilton Avenue
Menlo Park, CA 94025
Fax:   (650) 752-0202
Attn:  President

With a copy to the above address,
Attn:  General Counsel
Fax:   (650) 752-0220

IF TO GLAXO:

GLAXO GROUP LIMITED
Glaxo Wellcome House

Berkeley Avenue
Greenford
Middlesex UB6 ONN
United Kingdom
Fax:  (0044) (0)208 966 8837
Attn: The Company Secretary,

16.     MISCELLANEOUS

         16.1     ASSIGNMENT. Except as otherwise expressly provided under this
Agreement, neither this Agreement nor any right or obligation hereunder may be
assigned or otherwise transferred (whether voluntarily, by operation of law or
otherwise), without the prior express written consent of the other party;
provided, however, that either party may (in the absence of "good reason" as
defined in Section 9.5.1 of the Collaboration Agreement), assign this Agreement
and its rights and obligations hereunder in connection with the transfer or sale
of all or substantially all of its business, or in the event of its merger,
consolidation, change in control or similar transaction. Any permitted assignee
shall assume all obligations of its assignor under this Agreement. Any purported
assignment or transfer in violation of this Section 16.1 shall be void.

         16.2     AMENDMENTS; WAIVER. No provision of this Agreement, a Budget
or a Scope of Work may be amended, modified, revoked, or waived except in
writing signed and delivered by an authorized officer of each Party. Either
Party's failure to require the other Party to comply with the provisions of this
Agreement shall not be deemed a waiver of such provision or any other provision
of this Agreement.

         16.3     VALIDITY. If any clause, section or paragraph of this
Agreement is determined by a court of competent jurisdiction to be illegal,
invalid or unenforceable, it will be deemed severed from the remainder of this
Agreement and will have no effect on the legality, validity or enforceability of
the remaining provisions.

         16.4     HEADINGS. The paragraph headings of this Agreement are merely
for the convenience of the parties and are not to be construed as modifying or
changing the

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       15
<PAGE>

obligations or conditions expressed in this Agreement.

         16.5     ENTIRETY. This Agreement (including the Attachments hereto)
represents the entire understanding as of the Agreement Date hereof between the
parties with respect to the matter hereof and supersedes all prior agreements,
negotiations, understandings, representations, statements and writings between
the parties relating thereto.

         16.6     CONFLICT WITH SCOPE OF WORK OR BUDGET. If any terms of this
Agreement are in conflict with any terms of any Scope of Work or Budget, the
terms of this Agreement shall govern.

         16.7     COUNTERPARTS. This Agreement may be executed in several
counterparts, each of which shall be deemed an original but all of which shall
constitute one and the same instrument.

         16.8     GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with the laws of New York, without regard to its
conflicts of law principles.

         16.9     FURTHER ACTIONS. Each Party agrees to execute, acknowledge and
deliver such further instruments, and to do all other acts, as may be necessary
or appropriate in order to carry out their obligations under this Agreement.

         IN WITNESS WHEREOF, the Parties hereto through each of their respective
duly authorized representatives have caused this Agreement to be executed as of
the Agreement Date.

<TABLE>
<S><C>
GLAXO GROUP LIMITED                    DELTAGEN, INC.



By:  /s/ F. M. Bicknell                By: /s/ William Matthews
   ---------------------------------      -----------------------------------------

Name: F.M. Bicknell                    Name: William Matthews
     -------------------------------        ---------------------------------------

Title: Assistant Corporate Secretary   Title: President and Chief Executive Officer
      ------------------------------         --------------------------------------


GLAXO RESEARCH AND DEVELOPMENT LIMITED



By: /s/ F. M. Bicknell
   -----------------------------------

Name: F.M. Bicknell
     ---------------------------------

Title: Corporate Secretary
      --------------------------------
</TABLE>

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       16
<PAGE>

                                  ATTACHMENT I


                            SCOPE OF WORK AND BUDGET



               SCIENTIFIC MILESTONES AND PAYMENT SCHEDULE FOR ***

         Payments to DELTAGEN shall be based on the achievement of the specific
Milestones for each Project as outlined below. GLAXO understands and
acknowledges that each Project involves a number of technologically complex
steps and that any time periods for performance are reasonable estimates only
and subject to change due to technological difficulties encountered. DELTAGEN
shall be obligated to notify GLAXO of any such technical difficulties as soon as
reasonably possible after they arise and the parties will commence good faith
discussions to resolve such technical difficulties in a reasonable manner.

STANDARD KNOCKOUT MICE PROJECTS

<TABLE>
<S>                                                                   <C>
Total cost for each Standard Knockout Mice Project:                   ***

The following payments are per each Standard Knockout Mice Project:

***                                                                   ***

***                                                                   ***

***                                                                   ***

***                                                                   ***
</TABLE>

If requested by GLAXO, the following additional services would be provided at
the additional costs set forth below:

         For *** analysis of the resulting Standard Knockout Mice, an additional
payment of ***;

         For *** of an *** after *** of the *** under Milestone 1 below,
DELTAGEN would perform Milestones 1 and 2 as follows: For *** *** based upon
such *** (up to ***), an additional payment negotiated on a case-by-case
basis (***) (the "*** Milestone"); and

         For *** beyond the *** by DELTAGEN as set forth in Milestone 2
(other than *** associated with the ***), DELTAGEN ***at GLAXO's request for
an additional cost of *** for each *** (the "***").

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       17
<PAGE>

PAYMENT MILESTONES FOR A STANDARD KNOCKOUT MICE PROJECT

The Milestones for a Standard Knockout Project would be as follows:

MILESTONE 1: ***. DELTAGEN will *** based on *** received from GLAXO. The cost
of *** is included in the initiation payment paid by GLAXO. GLAXO will receive
*** information in order to confirm the gene ***in the ***. In the event of
unforeseen technical difficulties encountered after *** relating to the ***,
either (a) DELTAGEN would, upon consultation with GLAXO, *** at no additional
cost to GLAXO (one time), (b) GLAXO could terminate the particular Project or
(c) GLAXO could request that ***. *** would be provided at costs set forth in
the *** Milestone above.

***. DELTAGEN would *** and select ***. DELTAGEN would *** up to *** for
identification of at least *** and a maximum of up to ***. In the event that
DELTAGEN is only able to *** and GLAXO requests that DELTAGEN ***, or if ***
within the *** of the ***, DELTAGEN, after consultation with GLAXO, would either
(a) *** and *** and *** up to an additional *** at the costs specified for the
*** Milestone or (b) *** at the costs specified for the *** Milestone. The ***
would be analyzed through ***. GLAXO would also receive *** in order to confirm
the ***.

MILESTONE 2: ***. DELTAGEN would *** a minimum of *** and up to a maximum of ***
mice. DELTAGEN would provide to GLAXO by delivery FOB GLAXO's designated
carrier, either *** mice or *** mice. GLAXO shall promptly and reasonably
confirm *** using ***. If *** reasonably demonstrates that *** with the *** mice
or *** provided by DELTAGEN to GLAXO, DELTAGEN would provide to GLAXO *** mice
or *** capable of ***, provided that GLAXO properly and reasonably conducted
***. Prior to DELTAGEN providing such additional *** mice or ***, GLAXO would
demonstrate to DELTAGEN's reasonable satisfaction that ***.

GLAXO would have the right to terminate a particular Standard Knockout Mice
Project at any time (after payment in full of the next applicable Milestone
payment) but without further obligation to proceed with additional Milestones
with respect to the particular Standard Knockout Mice Project).

STARTING MATERIALS FOR A STANDARD KNOCKOUT MICE PROJECT

The costs set forth above would be dependent upon GLAXO providing to DELTAGEN
the following "Starting Materials" for Standard Knockout Mice Projects and GLAXO
would be responsible for providing to DELTAGEN such Starting Materials in order
for DELTAGEN to undertake a Standard Knockout Mice Project at such costs. The
Starting Materials for a Standard Knockout Mice Project shall be *** reasonably
required by Deltagen as mutually agreed to by the parties for Deltagen to
commence Milestone 1 above.



CONDITIONAL KNOCKOUT MICE PROJECTS ***

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       18
<PAGE>

<TABLE>
<S>                                                                  <C>
Total cost for each *** Conditional Knockout Mice Project:                  ***

The following Milestone payments are per each *** Conditional Knockout Mice
Project:

Milestone 1 ***                                                             ***

Milestone 2 ***                                                             ***

Milestone 3 ***                                                             ***

Milestone 4 ***                                                             ***
</TABLE>

If requested by GLAXO, the following additional services would be provided at
the additional costs set forth below:

         For ***and *** analysis of mice generated/provided under a Conditional
Knockout Mice Project, an additional payment of ***;

         For *** analysis of mice generated/provided under a Conditional
Knockout Mice Project, an additional payment of ***.

Total cost for each *** Mouse in a Conditional Knockout Mice Project:

         Available *** Mouse - Where DELTAGEN has the *** Mouse in its
possession and DELTAGEN has the *** Mouse to GLAXO, the cost for such Cre Mouse
shall be ***

         Custom *** Mouse - Where DELTAGEN is required to design, generate and
deliver such *** Mouse to GLAXO, the cost for such *** Mouse shall be ***

The following Milestone payments are per each *** Mouse Conditional Knockout
Mice Project:

<TABLE>
<S>                                                                         <C>
Milestone 1 ***                                                             ***

Milestone 2 ***                                                             ***

Milestone 3 ***                                                             ***

Milestone 4 ***                                                             ***
</TABLE>

If requested by GLAXO, the following additional services would be provided at
the costs set forth below:

         For *** and *** analysis of mice generated/provided under a Conditional
Knockout Mice Project, an additional payment of ***;

         For *** analysis of mice generated/provided under a Conditional
Knockout Mice Project, an additional payment of ***.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       19
<PAGE>

PAYMENT MILESTONES FOR A CONDITIONAL KNOCKOUT MICE PROJECT

The Milestones for a Conditional Knockout Mice Project would be as follows:

MILESTONE 1: ***. DELTAGEN will commence the project after reviewing the ***
provided by GLAXO. These include:

         ***;

         *** relating to ***; and

         ***.

         If DELTAGEN determines that there is insufficient information or
materials to commence the project, DELTAGEN will discuss with GLAXO the steps
that DELTAGEN believes are reasonably necessary to obtain the needed information
or materials.

MILESTONE 2: ***. DELTAGEN would *** based on *** that would be provided to
DELTAGEN by GLAXO. In the event of unforeseen technical difficulties encountered
after *** relating to ***, either (a) DELTAGEN would, upon consultation with
GLAXO *** at no additional cost to GLAXO (one time), (b) GLAXO could terminate
the particular Conditional Knockout Mice Project or (c) GLAXO could request that
DELTAGEN ***). *** would be provided at the costs set forth in the *** Milestone
above.

Completion of this milestone will be determined by ***. DELTAGEN will provide
*** to GLAXO for approval.

MILESTONE 3: ***. DELTAGEN would *** and ***. DELTAGEN would *** up to *** for
identification of at least *** and a maximum of up to ***. In the event that
DELTAGEN is only able to identify *** and GLAXO requests that DELTAGEN identify
***, or if *** within the initial *** of the ***, DELTAGEN, after consultation
with GLAXO, would either (a) *** and *** with the *** and *** up to *** at the
costs specified for the *** Milestone or (b) *** at the costs specified for the
*** Milestone. The identification of a *** would be analyzed through ***.

MILESTONE 4: ***. DELTAGEN would *** a minimum of *** and up to a maximum of ***
mice. DELTAGEN would provide to GLAXO by delivery FOB GLAXO's designated
carrier, either *** mice or *** mice. GLAXO shall promptly and reasonably
confirm *** using ***. If *** reasonably demonstrates that *** with the *** mice
or *** provided by DELTAGEN to GLAXO, DELTAGEN would provide to GLAXO *** mice
or ***, provided that GLAXO properly and reasonably conducted ***. Prior to
DELTAGEN providing such *** mice or ***, GLAXO would demonstrate to DELTAGEN's
reasonable satisfaction ***.

GLAXO would have the right to terminate a particular Conditional Knockout Mice
Project at any time (after payment in full of the next applicable Milestone
payment) but without further obligation to proceed with additional Milestones
with respect to the particular Conditional Knockout Mice Project).

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       20
<PAGE>

STARTING MATERIALS FOR A CONDITIONAL KNOCKOUT MICE PROJECT

The costs set forth above would be dependent upon GLAXO providing to DELTAGEN
the following "Starting Materials" for Conditional Knockout Mice Projects and
GLAXO would be responsible for providing to DELTAGEN such Starting Materials in
order for DELTAGEN to undertake a Conditional Knockout Mice Project at such
costs. The Starting Materials for a Conditional Knockout Mice Project are the
following materials and information:

         ***

                  -- The ***

         The ***

                  -- GLAXO would also need to provide all ***

         *** for the *** by DELTAGEN



KNOCK-IN MICE PROJECT

<TABLE>
<S>                                                                  <C>
Total cost for each Knock-In Mice Project:                            ***

The following payments are per each Knock-In Mice Project:

Milestone 1 ***                                                       ***

Milestone 2 ***                                                       ***

Milestone 3 - ***                                                     ***

Milestone 4 ***                                                       ***
</TABLE>

If requested by GW, the following additional services would be provided at the
additional costs set forth below:

         For *** and *** analysis of mice generated/provided under a Knock-In
Mice Project, a payment of ***;

         For *** analysis of mice generated/provided under a Knock-In Mice
Project, a payment of ***.

PAYMENT MILESTONES FOR A KNOCK-IN MICE PROJECT

The Milestones for a Knock-In Mice Project would be as follows:

MILESTONE 1 ***. DELTAGEN will commence the project after reviewing the *** and
***

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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<PAGE>

provided by GLAXO.

If DELTAGEN determines that there is insufficient information or materials to
commence the project, DELTAGEN will discuss with GLAXO what steps are reasonably
necessary to obtain the needed information or materials.

MILESTONE 2: ***. DELTAGEN would *** based on *** that would be provided to
DELTAGEN by GLAXO. In the event of unforeseen technical difficulties encountered
after *** relating to the ***, either (a) DELTAGEN would, upon consultation with
GLAXO, *** at no additional cost to GLAXO (one time), (b) GLAXO could terminate
the particular Knock-In Mice Project or (c) GLAXO could request that DELTAGEN
***). *** would be provided at the costs set forth in the *** Milestone above.

Completion of this milestone will be determined by *** to confirm the ***.
DELTAGEN will provide this *** to GLAXO for approval.

MILESTONE 3: ***. DELTAGEN would *** and ***. DELTAGEN would *** up to *** for
identification of at least *** and a maximum of up to *** that have undergone
***. In the event that DELTAGEN is only able to *** and GLAXO requests that
DELTAGEN identify ***, or if *** within the *** of the ***, DELTAGEN, after
consultation with GLAXO, would either (a) *** and *** and *** up to *** at the
costs specified for the *** Milestone or (b) *** at the costs specified for the
*** Milestone. The identification of a *** would be analyzed through ***.

MILESTONE 4: ***. DELTAGEN would *** a minimum of *** and up to a maximum of ***
*** mice. DELTAGEN would provide to GLAXO by delivery FOB GLAXO's designated
carrier, either *** mice or *** mice. GLAXO shall promptly and reasonably
confirm *** using ***. If *** reasonably demonstrates *** has occurred with the
*** or *** provided by DELTAGEN to GLAXO, DELTAGEN would provide to GLAXO ***
mice or ***, provided that GLAXO properly and reasonably conducted ***. Prior to
DELTAGEN providing *** mice or ***, GLAXO would demonstrate to DELTAGEN's
reasonable satisfaction ***.

GLAXO would have the right to terminate a particular Knock-In Mice Project at
any time (after payment in full of the next applicable Milestone payment) but
without further obligation to proceed with additional Milestones with respect to
the particular Knock-In Mice Project).

STARTING MATERIALS FOR A KNOCK-IN MICE PROJECT

The costs set forth above would be dependent upon GLAXO providing to DELTAGEN
the following "Starting Materials" for Knock-In Mice Projects and GLAXO would be
responsible for providing to DELTAGEN such Starting Materials in order for
DELTAGEN to undertake a Knock-In Mice Project at such costs. The Starting
Materials for a Knock-In Mice Project are the following materials and
information:

         ***

                  -- The ***

         The ***

                  -- GLAXO would also need to provide all *** events

         *** for the *** by DELTAGEN

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       22
<PAGE>

                                  ATTACHMENT II



            FORM NOTIFICATION LETTER FOR INITIATION OF A NEW PROJECT





                               (Template follows)

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                       23
<PAGE>

                               (GLAXO letterhead)



______________, _____



William Matthews, Ph.D.
President
Deltagen, Inc.
1003 Hamilton Avenue
Menlo Park, CA 94025

Dear Bill,

This letter is to provide notice to DELTAGEN of GLAXO's request to DELTAGEN to
initiate work on a Project under the terms and conditions of the DeltaSelect-TM-
Collaborative Services Agreement between DELTAGEN, Inc. and GLAXO, dated
______________ (the "Agreement"), including but not limited to, the
confidentiality obligations of the Agreement.

The Project to be initiated is described as follows:





The GLAXO contact scientist for technical information regarding the Project will
be:





GLAXO requests that DELTAGEN begin to work to develop the above described
Project on the terms and conditions of the above-referenced Agreement.

Sincerely,



[GLAXO RESEARCH INSTITUTE'S Signatory]

Agreed,


______________________
Deltagen, Inc.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


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