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                                                                    EXHIBIT 10.2

                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                          UNDER 17 C.F.R. SECTIONS 200.80(b)(4),
                                                            200.83 AND 240.24B-2
                                                           Agreement No. 99-0036

                            SPONSOR OPTION AGREEMENT

        THIS AGREEMENT, dated and effective as of April 23, 1999, is by and
between the Wisconsin Alumni Research Foundation ("WARF"), a nonstock, nonprofit
Wisconsin corporation, and Geron Corporation ("Sponsor"), a Delaware
corporation.

                              PURPOSE OF AGREEMENT

        WHEREAS, Sponsor, pursuant to a separate agreement with the University
of Wisconsin-Madison ("University"), has committed Financial Support (defined
below) to the University for the purpose of conducting research;

        WHEREAS, WARF is willing and hereby offers to grant options to take
licenses to additional cell types not covered by the License Agreement (defined
below), wherein such option is defined in the License Agreement, and further
offers to grant options to any other invention arising from the Financial
Support provided to the University by the Sponsor and under certain patents or
patent applications which are or will be assigned to WARF, and Sponsor hereby
states its desire for such options;

        NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth below, the parties covenant and agree as follows:

        Section 1. DEFINITIONS.

        For the purposes of this Agreement, the Appendix 1 definitions shall
apply.

        Section 2. GRANT OF OPTIONS TO LICENSES.

                A.      Future Notification and Option to Future Patents.

                        (i)     WARF shall notify Sponsor of any Future Patents
by sending Sponsor a written disclosure from the inventor or a copy of the U.S.
Patent Application claiming such invention. Such disclosure shall be considered
confidential information subject to the obligations set forth in Section 7
hereto. WARF shall not be obligated to grant any rights to Sponsor concerning
any inventions, disclosures or applications provided to Sponsor pursuant to this
Section 2B(i) except as provided in Section 2B(ii).

                        (ii)    Sponsor shall have an option to add any Future
Patents to the Licensed Patents under the license granted by the License
Agreement. Sponsor must exercise such option within ninety (90) days after
receiving a copy of U.S. Patent Application (without claims) by written
notification to WARF including a Development Plan detailing Sponsor's plan and
timeline for bringing Products to market incorporating the Future Patents and
paying WARF a license fee for the Future Patent. The license fee shall be
negotiated in good faith for each new U.S. patent application added to the
Licensed Patents under the License Agreement. In addition, Sponsor shall pay to
WARF patent reimbursement as set forth in Section 4C of the License Agreement.



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                C.      U.S. Government Interests.

        It is understood that if the United States Government (through any of
its agencies or otherwise) has funded research, during the course of or under
which any of the inventions of the Future Patents were or are conceived or made,
the United States Government is entitled, as a right, under the provisions of 35
U.S.C. Section 200-212 and applicable regulations of Chapter 37 of the Code of
Federal Regulations, to a nonexclusive, nontransferable, irrevocable, paid-up
license to practice or have practiced the invention of such Future Patents for
governmental purposes. Any license granted to Sponsor in this Agreement shall be
subject to such right.

        Section 3. CONSIDERATION.

        The consideration for the options is the Financial Support, which is
accepted by WARF in lieu of any separate option fees, which otherwise would have
been required by WARF.

        Section 4. CERTAIN WARRANTIES OF WARF.

        WARF makes no warranty other than WARF warrants that the Principal
Investigator ("PI") and Researchers have entered into the agreement set forth in
Appendix 4 to assign to WARF all inventions that any of them conceive and reduce
to practice during and as a part of the Research Program. PI has further agreed
to require each additional Researcher who may work on the Research Program to
accept the same obligation to assign. (See Appendix 3.) Furthermore, nothing in
this Agreement shall be construed as an obligation by WARF to provide Sponsor
with any know-how or materials not provided in Future Patents.

        Section 5. TERMINATION.

        This Agreement shall be subject to termination under the following
circumstances:

                A.      This Agreement shall terminate on [...***...] unless
Sponsor and WARF have agreed to extend the option for an additional term and
Sponsor has provided the Financial Support of the Research Program as required
by the University for such extension.

                B.      This Agreement shall terminate if the Research
Agreement, or its successor agreement, is terminated for any reason.

                C.      Sponsor may terminate this Agreement at any time upon
giving WARF thirty (30) days' written notice but only with respect to its
obligations to WARF and WARF's obligations to Sponsor.

        Section 6. ASSIGNMENT.

        This Agreement may not be transferred or assigned by Sponsor except to a
company in which Sponsor owns at least fifty percent (50%) of the equity; upon
sale or transfer of substantially all the assets of Sponsor or with the prior
written consent of WARF.

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[...***...] = MATERIAL HAS BEEN OMITTED PURSUANT TO A REQUEST FOR CONFIDENTIAL
TREATMENT AND HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION.



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        Section 7. CONFIDENTIALITY.

        A.      Both parties agree to hold the other party's confidential
information in confidence using procedures at least as stringent as the
receiving party uses to protect its own confidential information. Each party
shall mark all confidential information confidential or, if disclosed orally,
such information shall be identified to the receiving party as confidential at
the time of the oral disclosure and the disclosing party shall confirm the
confidentiality of such oral information by letter to the receiving party no
later than ten (10) days after the oral disclosure. Confidential information
shall not include any information:

        (a)     known to the receiving party at the time of disclosure by the
disclosing party;

        (b)     known or available to the public at the time of the disclosure
or thereafter; or

        (c)     disclosed to receiving party in good faith by another party
having the right to disclose such information.

        B.      All information regarding inventions conceived or reduced to
practice during the course of or under the Research Program which is disclosed
by PI or Researchers to Sponsor shall be considered confidential.

        Section 8. NOTICE.

        Any notice required to be given pursuant to the provisions of this
Agreement shall be in writing and shall be deemed to have been given at the
earlier of the time when actually received as a consequence of any effective
method of delivery, including but not limited to hand delivery, transmission by
telecopier, or delivery by a professional courier service or the time when sent
by certified or registered mail addressed to the party for whom intended at the
address below or at such changed address as the party shall have specified by
written notice, provided that any notice of change of address shall be effective
only upon actual receipt.

        (a)     Wisconsin Alumni Research Foundation
                Attn: Managing Director
                614 Walnut Street
                Madison, Wisconsin  53705

        (b)     Geron Corporation
                Attn: Vice President of Corporate Development
                200 Constitution Drive
                Menlo Park, CA  94025

        Section 9.  AMENDMENT AND CHOICE OF LAWS.

        This Agreement may not be amended except by written, mutual agreement of
the parties expressly set forth as an amendment hereto. This Agreement shall be
governed by the laws of the State of Wisconsin.

        Section 10. AUTHORITY.

        The persons signing on behalf of WARF and Sponsor hereby warrant and
represent that they have authority to execute this Agreement on behalf of the
party for whom they have signed.

        IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement
on the dates



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indicated below.

        WISCONSIN ALUMNI RESEARCH FOUNDATION

By: /s/ Richard H. Leazer                         Date: 5/6/99
   -----------------------------------------
     Richard H. Leazer, Managing Director

        GERON CORPORATION

By: /s/ David L. Greenwood                        Date: 5/6/99
   -----------------------------------------

Name & Title:
             -------------------------------------------------

- --------------------------------------------------------------
Approved in by WARF's General Counsel:

/s/ Elizabeth L.R. Donley                        Date: April 22, 1999
- --------------------------------------------
Elizabeth L.R. Donley



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                                   APPENDIX 1

        1.      "Research Program" shall be limited to the ongoing program of
research described in Appendix 2 during the period such program is funded by
Sponsor pursuant to the Research Agreement.

        2.      "Principal Investigator" shall be the individual identified in
the University of Wisconsin Principal Investigator Patent Agreement, attached as
Appendix 3.

        3.      "Researchers" shall be limited to individuals performing
research under the Research Program who have signed the University of Wisconsin
Researcher and Patent Agreement which is attached as Appendix 4.

        4.      "Development Plan" shall mean a summary overview of the
activities believed necessary to commercialize an invention of the Future
Patents or to bring Products relating to cell types to market.

        5.      "Research Agreement" shall refer to and mean a separate,
contemporaneous agreement between Sponsor and the University, a copy of which is
attached as Appendix 5.

        6.      "Financial Support" shall refer to and mean funds provided by
Sponsor to the University in support of the Research Program in an amount of at
least $[...***...] for the period April 1, 1998 to March 31, 1999; $[...***...]
for the year beginning on April 1, 1999 to March 31, 2000; and $[...***...] for
the year beginning on April 1, 2000 to March 31, 2001 to support further
research by Professor Thomson at the University of Wisconsin - Madison.

        7.      "Future Patents" shall be limited to any patent or patent
application arising out of any invention which is conceived and reduced to
practice under and during the course of the Research Program and which is
assigned to WARF by Principal Investigator or Researchers.

        8.      "Licensed Field" shall be limited to therapeutic and diagnostic
treatments for humans which are covered by one or more claims of the Licensed
Patents.

        9.      "License Agreement" shall refer to and mean Agreement No.
99-0027, of even date herewith, entered into by the parties hereto.


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[...***...] = MATERIAL HAS BEEN OMITTED PURSUANT TO A REQUEST FOR CONFIDENTIAL
TREATMENT AND HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION



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                                   APPENDIX 2

                                RESEARCH PROGRAM

                           (To be provided by Sponsor)



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                                   APPENDIX 3

                             UNIVERSITY OF WISCONSIN

                     PRINCIPAL INVESTIGATOR PATENT AGREEMENT

James A. Thomson                              Principal Investigator
- ----------------------------------------

Geron Corporation                             Sponsor
- ----------------------------------------

        I am the above Principal Investigator at the University of Wisconsin on
the Research Program as described in Appendix 2 hereto. I understand that the
Research Program is now or is soon to be supported, directly or indirectly by
funds supplied by the Sponsor. I understand and agree that Sponsor's support of
the Research Program is being accepted in lieu of the option fees which might
otherwise be charged for the technology resulting from the Research Program and
that such support will not be part of the basis for the gross income relied on
by WARF for payment of any royalty shares to the inventors for any licenses of
patents or other technology resulting from this research.

        In consideration for such support, I hereby agree and obligate myself to
disclose promptly to the Wisconsin Alumni Research Foundation (WARF) any
invention conceived of or reduced to practice by me, whether solely or jointly
by others, resulting in whole or in part from activity undertaken by me as a
part of the Research Program. I so agree and obligate myself on the condition
that WARF will consider the patentability and the licensability of any such
invention and advise me of WARF's interest in taking title to the invention and
pursuing patent protection for it.

        At the sole option of WARF and if WARF so requests, I agree to assign to
WARF all my right, title and interest in such invention in the United States,
its territories and possessions and in all foreign countries. The making of this
assignment shall be conditioned solely upon WARF's willingness to accord to me
the benefit of its then-standard Memorandum Agreement for use with University
inventors assigning inventions to WARF, a copy of such Agreement shall be
executed both by me and WARF.

        I also agree to require any other researchers working on the Research
Program to similarly assign their rights in any such inventions to WARF. To
fulfill this obligation, I will require that each investigator sign a copy of
the University of Wisconsin Investigator and Patent Agreement attached hereto as
Appendix 4, and forward the signed copy to WARF. All such inventors assigning to
WARF will have the same opportunity for financial reward as any other University
inventor who brings an invention to WARF under the terms of the then-standard
Memorandum Agreement.

__________________________________________ Principal Investigator


Dated: ___________________________________



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                                   APPENDIX 4

            UNIVERSITY OF WISCONSIN INVESTIGATOR AND PATENT AGREEMENT

                                         Researcher
- ----------------------------------------

            James A. Thomson             Principal Investigator(s)
- ----------------------------------------

            Geron Corporation            Sponsor
- ----------------------------------------

        I am the University of Wisconsin researcher identified above. I am about
to enter into research forming part of the Research Program described in
Appendix 2 conducted by the above Principal Investigator(s) at the University of
Wisconsin that is covered by an Agreement between WARF, and the above Sponsor.
As a consequence, the research work I am about to undertake may be supported,
directly or indirectly, by a grant from the Sponsor. I understand and agree that
Sponsor's support of the Research Program is being accepted in lieu of the
option fees which might otherwise be charged for the technology resulting from
the Research Program and that such support will not be part of the basis for the
gross income relied on by WARF for payment of any royalty shares to the
inventors for any licenses of patents or other technology resulting from this
research.

        In consideration for such support, I hereby agree and obligate myself to
disclose promptly to the Wisconsin Alumni Research Foundation (WARF) any
invention conceived of or reduced to practice by me, whether solely or jointly
with others, resulting in whole or in part from activity undertaken by me as
part of the Research Program. I so agree and obligate myself on the condition
that WARF will consider the patentability and the licensability of any such
invention and advise me of WARF's interest in taking title to the invention and
pursuing patent protection for it.

        At the sole option of WARF and if WARF so requests, I agree to assign to
WARF all right, title, and interest in any such invention in the United States,
its territories and possessions and in all foreign countries. The making of this
assignment shall be conditioned solely upon WARF's willingness to accord to me
the benefit of its then-standard Memorandum Agreement for use with University
inventors assigning inventions to WARF, a copy of which Agreement shall be
executed both by me and by WARF.

                                         Researcher
- ----------------------------------------


- ----------------------------------------
                  Date



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                                   APPENDIX 5

                               RESEARCH AGREEMENT

                        (To be provided by Sponsor prior
                         to execution of this Agreement)



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