Document:

EXHIBIT B
                                                                     TO PURCHASE
                                                                       AGREEMENT

                                                                Right to
                                                                Purchase -------
                                                                Shares of
                                                                Common Stock,
                                                                par value $0.001
                                                                per share

                     FORM OF COMMON STOCK PURCHASE WARRANT B

     THIS CERTIFIES THAT, for value received, subject to Section 2 hereof, _____
(the "Holder") or its registered assigns, is entitled to purchase from Geron
Corporation, a Delaware corporation (the "Company"), at any time or from time to
time during the period specified in Paragraph 2 hereof, _____ (_____ ) fully
paid and nonassessable shares of the Company's common stock, par value $0.001
per share (the "Common Stock"), at an exercise price of $6.10 per share (the
"Exercise Price"). The term "Warrant Shares," as used herein, refers to the
shares of Common Stock purchasable hereunder. The Warrant Shares and the
Exercise Price are subject to adjustment as provided in Paragraph 4 hereof. The
term "Warrants" means this Warrant and the other warrants (including the A
Warrants and the C Warrants (each as defined in the Purchase Agreement)) issued
pursuant to that certain Securities Purchase Agreement, dated November 10, 2004,
by and among the Company and the Buyers listed on the execution page thereof
(the "Purchase Agreement").

         This Warrant is subject to the following terms, provisions, and
conditions:

1. Manner of Exercise; Issuance of Certificates; Payment for Warrant Shares. (a)
Subject to the provisions hereof, this Warrant may be exercised by the Holder,
in whole or in part, by the surrender of this Warrant, together with a completed
exercise agreement in the form attached hereto (the "Exercise Agreement"), to
the Company during normal business hours on any business day at the Company's
principal executive offices (or such other office or agency of the Company as it
may designate by notice to the Holder), and upon payment to the Company in cash,
by certified or official bank check or by wire transfer for the account of the
Company of the Exercise Price for the Warrant Shares specified in the Exercise
Agreement. The Warrant Shares so purchased shall be deemed to be issued to the
Holder or such holder's designee, as the record owner of such shares, as of the
close of business on the date on which this Warrant shall have been surrendered,
the completed Exercise Agreement shall have been delivered, and payment shall
have been made for such shares as set forth above. In the event of any exercise
of the rights represented by this Warrant in accordance with and subject to the
terms and conditions hereof, the Warrant Shares shall be issued and delivered to
the Depository Trust Company account on the Holder's behalf via the Deposit
Withdrawal Agent Commission system ("DWAC Transfer") within a reasonable time,
not exceeding two (2) trading days after such exercise (or, if DWAC Transfer is

<PAGE>

not available or Holder otherwise requests in writing, certificates for the
Warrant Shares shall be issued, dated the date of such exercise and delivered to
the Holder hereof within a reasonable time, not exceeding three (3) trading days
after such exercise), and the Holder hereof shall be deemed for all purposes to
be the holder of the Warrant Shares so purchased as of the date of such
exercise. Any certificates requested shall be delivered in such denominations as
may be requested by the Holder and shall be registered in the name of such
holder or such other name as shall be designated by such holder. If this Warrant
shall have been exercised only in part, then, unless this Warrant has expired,
the Company shall, at its expense, at the time of delivery of such certificates,
deliver to the holder a new Warrant representing the number of shares with
respect to which this Warrant shall not then have been exercised. In the event
an Exercise Agreement is delivered and the Company is unable to issue the
Warrant Shares, the Holder may, at its option, rescind such Exercise Agreement
and such rescission will not effect the Holder's right to an extension of the
Exercise Period pursuant to Section 4.13 of the Purchase Agreement.

         (b) Notwithstanding anything in this Warrant to the contrary, in no
event shall the Holder of this Warrant be entitled to exercise a number of
Warrants (or portions thereof) in excess of the number of Warrants (or portions
thereof) upon exercise of which the sum of (i) the number of shares of Common
Stock beneficially owned by the Holder and its affiliates (other than shares of
Common Stock which, but for this proviso, may be deemed beneficially owned
through the ownership of the unexercised Warrants and the unexercised or
unconverted portion of any other securities of the Company subject to a
limitation on conversion or exercise analogous to the limitation contained
herein) and (ii) the number of shares of Common Stock issuable upon exercise of
the Warrants (or portions thereof) with respect to which the determination
described herein is being made, would result in beneficial ownership by the
Holder and its affiliates of more than 4.9% of the outstanding shares of Common
Stock. For purposes of the immediately preceding sentence, beneficial ownership
shall be determined in accordance with Section 13(d) of the Securities Exchange
Act of 1934, as amended, and Regulations 13D-G thereunder, except as otherwise
provided in clause (i) hereof. Notwithstanding anything in this Warrant to the
contrary, the restrictions on exercise of this Warrant set forth in this
paragraph shall not be amended without (i) the written consent of the Holder and
the Company and (ii) the approval of the holders of a majority of the Common
Stock present, or represented by proxy, and voting at any meeting called to vote
on the amendment of such restriction.

2. Period of Exercise. This Warrant is exercisable at any time or from time to
time on or after the date on which this Warrant is issued and delivered pursuant
to the terms of the Purchase Agreement (the "Issue Date") and before 8:00 p.m.,
New York City time on January 11, 2005 (the "Exercise Period"); provided,
however, that:

         (i) on January 11, 2005, if the Holder pays an extension fee of $6.09
per share (the "Extension Fee"), to the Company in cash, by certified or
official bank check or by wire transfer for the account of the Company (which
Extension Fee is non-refundable), the "Exercise Period" shall be extended to
November 12, 2007 with respect to that number of Warrant Shares determined by
dividing (i) the aggregate amount of the Extension Fee paid by (ii) $6.09;
provided, further, that after January 11, 2005, if the Exercise Period has been
extended pursuant to the terms of this Section 2 upon payment of the Extension
Fee to the Company, the Exercise Price per share shall equal $0.01; and

<PAGE>

         (ii) the Exercise Period will be extended in accordance with Section
4.13 of the Purchase Agreement upon the occurrence of events set forth in such
section.

     3. Certain Agreements of the Company. The Company hereby covenants and
agrees as follows:

     (a) Shares to be Fully Paid. All Warrant Shares will, upon issuance in
accordance with the terms of this Warrant, be validly issued, fully paid, and
nonassessable and free from all taxes, liens, and charges with respect to the
issue thereof.

     (b) Reservation of Shares. During the Exercise Period, the Company shall at
all times have authorized, and reserved for the purpose of issuance upon
exercise of this Warrant, a sufficient number of shares of Common Stock to
provide for the full exercise of this Warrant.

     (c) Listing. The Company shall promptly secure the listing of the Warrant
Shares upon each national securities exchange or automated quotation system, if
any, upon which shares of Common Stock are then listed (subject to official
notice of issuance upon exercise of this Warrant) and shall maintain, so long as
any other shares of Common Stock shall be so listed, such listing of all Warrant
Shares; and the Company shall so list on each national securities exchange or
automated quotation system, as the case may be, and shall maintain such listing
of, any other shares of capital stock of the Company issuable upon the exercise
of this Warrant if and so long as any shares of the same class shall be listed
on such national securities exchange or automated quotation system.

     (d) Certain Actions Prohibited. The Company will not, by amendment of its
charter or through any reorganization, transfer of assets, consolidation,
merger, dissolution, issue or sale of securities, or any other voluntary action,
avoid or seek to avoid the observance or performance of any of the terms to be
observed or performed by it hereunder, but will at all times in good faith
assist in the carrying out of all the provisions of this Warrant and in the
taking of all such action as may reasonably be requested by the holder of this
Warrant in order to protect the exercise privilege of the holder of this Warrant
against dilution or other impairment, consistent with the tenor and purpose of
this Warrant. Without limiting the generality of the foregoing, the Company (i)
will not increase the par value of any shares of Common Stock receivable upon
the exercise of this Warrant above the Exercise Price then in effect, and (ii)
will take all such actions as may be necessary or appropriate in order that the
Company may validly and legally issue fully paid and nonassessable shares of
Common Stock upon the exercise of this Warrant.

     (e) Successors and Assigns. This Warrant will be binding upon any entity
succeeding to the Company by merger, consolidation, or acquisition of all or
substantially all the Company's assets.

     4. Antidilution Provisions. During the Exercise Period, the Exercise Price
and the number of Warrant Shares shall be subject to adjustment from time to
time as provided in this Paragraph 4. In the event that any adjustment of the
Exercise Price as required herein results in a fraction of a cent, such Exercise
Price shall be rounded up to the nearest cent.

<PAGE>

     (a) Subdivision or Combination of Common Stock. If the Company at any time
subdivides (by any stock split, stock dividend, recapitalization,
reorganization, reclassification or otherwise) the shares of Common Stock
acquirable hereunder into a greater number of shares, then, after the date of
record for effecting such subdivision, the Exercise Price in effect immediately
prior to such subdivision will be proportionately reduced. If the Company at any
time combines (by reverse stock split, recapitalization, reorganization,
reclassification or otherwise) the shares of Common Stock acquirable hereunder
into a smaller number of shares, then, after the date of record for effecting
such combination, the Exercise Price in effect immediately prior to such
combination will be proportionately increased. "Common Stock," for purposes of
this Paragraph 4, includes the Common Stock, par value $0.001 per share, and any
additional class of stock of the Company having no preference as to dividends or
distributions on liquidation, provided that the shares purchasable pursuant to
this Warrant shall include only shares of Common Stock, par value $0.001 per
share, in respect of which this Warrant is exercisable, or shares resulting from
any subdivision or combination of such Common Stock, or in the case of any
reorganization, reclassification, consolidation, merger, or sale of the
character referred to in Paragraph 4(c) hereof, the stock or other securities or
property provided for in such Paragraph.

     (b) Adjustment in Number of Shares. Upon each adjustment of the Exercise
Price pursuant to the provisions of this Paragraph 4, the number of shares of
Common Stock issuable upon exercise of this Warrant shall be adjusted by
multiplying a number equal to the Exercise Price in effect immediately prior to
such adjustment by the number of shares of Common Stock issuable upon exercise
of this Warrant immediately prior to such adjustment and dividing the product so
obtained by the adjusted Exercise Price.

     (c) Consolidation, Merger or Sale. In case of any consolidation of the
Company with, or merger of the Company into any other corporation, or in case of
any sale or conveyance of all or substantially all of the assets of the Company
other than in connection with a plan of complete liquidation of the Company,
then as a condition of such consolidation, merger or sale or conveyance,
adequate provision will be made whereby the holder of this Warrant will have the
right to acquire and receive upon exercise of this Warrant in lieu of the shares
of Common Stock immediately theretofore acquirable upon the exercise of this
Warrant, such shares of stock, securities or assets as may be issued or payable
with respect to or in exchange for the number of shares of Common Stock
immediately theretofore acquirable and receivable upon exercise of this Warrant
had such consolidation, merger or sale or conveyance not taken place. In any
such case, the Company will make appropriate provision to insure that the
provisions of this Paragraph 4 hereof will thereafter be applicable as nearly as
may be in relation to any shares of stock or securities thereafter deliverable
upon the exercise of this Warrant. The Company will not effect any
consolidation, merger or sale or conveyance unless prior to the consummation
thereof, the successor or acquiring entity (if other than the Company) and, if
an entity different from the successor or acquiring entity, the entity whose
capital stock or assets the holders of the Common Stock of the Company are
entitled to receive as a result of such consolidation, merger or sale or
conveyance assumes by written instrument the obligations under this Paragraph 4
and the obligations to deliver to the holder of this Warrant such shares of
stock, securities or assets as, in accordance with the foregoing provisions, the
holder may be entitled to acquire.

<PAGE>

     (d) Distribution of Assets. In case the Company shall declare or make any
distribution of its assets (including cash) to holders of Common Stock as a
partial liquidating dividend, by way of return of capital or otherwise, then,
after the date of record for determining stockholders entitled to such
distribution, but prior to the date of distribution, the holder of this Warrant
shall be entitled upon exercise of this Warrant for the purchase of any or all
of the shares of Common Stock subject hereto, to receive the amount of such
assets which would have been payable to the holder had such holder been the
holder of such shares of Common Stock on the record date for the determination
of stockholders entitled to such distribution.

     (e) Notice of Adjustment. Upon the occurrence of any event which requires
any adjustment of the Exercise Price, then, and in each such case, the Company
shall give notice thereof to the holder of this Warrant, which notice shall
state the Exercise Price resulting from such adjustment and the increase or
decrease in the number of Warrant Shares purchasable at such price upon
exercise, setting forth in reasonable detail the method of calculation and the
facts upon which such calculation is based. Such calculation shall be certified
by the chief financial officer of the Company.

     (f) Minimum Adjustment of Exercise Price. No adjustment of the Exercise
Price shall be made in an amount of less than 1% of the Exercise Price in effect
at the time such adjustment is otherwise required to be made, but any such
lesser adjustment shall be carried forward and shall be made at the time and
together with the next subsequent adjustment which, together with any
adjustments so carried forward, shall amount to not less than 1% of such
Exercise Price.

     (g) No Fractional Shares. No fractional shares of Common Stock are to be
issued upon the exercise of this Warrant. If the exercise of this Warrant would
result in a fractional share of Common Stock, such fractional share shall be
disregarded and the number of shares of Common Stock issuable upon exercise of
the Warrant shall be the next higher number of shares.

     (h) Other Notices. In case at any time:

     (i) the Company shall declare any dividend upon the Common Stock payable in
shares of stock of any class or make any other distribution (including dividends
or distributions payable in cash out of retained earnings) to the holders of the
Common Stock;

     (ii) the Company shall offer for subscription pro rata to the holders of
the Common Stock any additional shares of stock of any class or other rights;

     (iii) there shall be any capital reorganization of the Company, or
reclassification of the Common Stock, or consolidation or merger of the Company
with or into, or sale of all or substantially all its assets to, another
corporation or entity; or

     (iv) there shall be a voluntary or involuntary dissolution, liquidation or
winding-up of the Company;

<PAGE>

then, in each such case, the Company shall give to the holder of this Warrant
(a) notice of the date on which the books of the Company shall close or a record
shall be taken for determining the holders of Common Stock entitled to receive
any such dividend, distribution, or subscription rights or for determining the
holders of Common Stock entitled to vote in respect of any such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation or
winding-up and (b) in the case of any such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation or winding-up, notice of
the date (or, if not then known, a reasonable approximation thereof by the
Company) when the same shall take place. Such notice shall also specify the date
on which the holders of Common Stock shall be entitled to receive such dividend,
distribution, or subscription rights or to exchange their Common Stock for stock
or other securities or property deliverable upon such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation, or
winding-up, as the case may be. Such notice shall be given at least 30 days
prior to the record date or the date on which the Company's books are closed in
respect thereto. Failure to give any such notice or any defect therein shall not
affect the validity of the proceedings referred to in clauses (i), (ii), (iii)
and (iv) above.

     (i) Certain Events. If any event occurs of the type contemplated by the
adjustment provisions of this Paragraph 4 but not expressly provided for by such
provisions, the Company will give notice of such event as provided in Paragraph
4(e) hereof, and the Company's Board of Directors will make an appropriate
adjustment in the Exercise Price and the number of shares of Common Stock
acquirable upon exercise of this Warrant so that the rights of the Holder shall
be neither enhanced nor diminished by such event.

5. Issue Tax. The issuance of certificates for Warrant Shares upon the exercise
of this Warrant shall be made without charge to the holder of this Warrant or
such shares for any issuance tax or other costs in respect thereof, provided
that the Company shall not be required to pay any tax which may be payable in
respect of any transfer involved in the issuance and delivery of any certificate
in a name other than the holder of this Warrant.

6. No Rights or Liabilities as a Stockholder. This Warrant shall not entitle the
Holder to any voting rights, dividend rights or other rights as a stockholder of
the Company. No provision of this Warrant, in the absence of affirmative action
by the Holder to purchase Warrant Shares, and no mere enumeration herein of the
rights or privileges of the Holder, shall give rise to any liability of such
holder for the Exercise Price or as a stockholder of the Company, whether such
liability is asserted by the Company or by creditors of the Company.

7. Transfer, Exchange, and Replacement of Warrant.

     (a) Transfer. This Warrant and the rights granted to the Holder are
transferable, in whole or in part, upon surrender of this Warrant, together with
a properly executed assignment in the form attached hereto, at the office or
agency of the Company referred to in Paragraph 7(e) below. Until due presentment
for registration of transfer on the books of the Company, the Company may treat
the registered Holder as the owner and Holder for all purposes, and the Company
shall not be affected by any notice to the contrary.

     (b) Warrant Exchangeable for Different Denominations. This Warrant is
exchangeable, upon the surrender hereof by the Holder at the office or agency of
the Company referred to in Paragraph 7(e) below, for new Warrants of like tenor
representing in the aggregate the right to purchase the number of shares of
Common Stock which may be purchased hereunder, each of such new Warrants to
represent the right to purchase such number of shares as shall be designated by
the Holder at the time of such surrender.

<PAGE>

     (c) Replacement of Warrant. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction, or mutilation of
this Warrant and, in the case of any such loss, theft, or destruction, upon
delivery of an indemnity agreement reasonably satisfactory in form and amount to
the Company, or, in the case of any such mutilation, upon surrender and
cancellation of this Warrant, the Company, at its expense, will execute and
deliver, in lieu thereof, a new Warrant of like tenor.

     (d) Cancellation; Payment of Expenses. Upon the surrender of this Warrant
in connection with any transfer, exchange, or replacement as provided in this
Paragraph 7, this Warrant shall be promptly canceled by the Company. The Company
shall pay all taxes (other than securities transfer taxes) and all other
expenses (other than legal expenses, if any, incurred by the Holder or
transferees) and charges payable in connection with the preparation, execution,
and delivery of Warrants pursuant to this Paragraph 7.

     (e) Register. The Company shall maintain, at its principal executive
offices (or such other office or agency of the Company as it may designate by
notice to the Holder), a register for this Warrant, in which the Company shall
record the name and address of the person in whose name this Warrant has been
issued, as well as the name and address of each transferee and each prior owner
of this Warrant.

8. Notices. All notices, requests, and other communications required or
permitted to be given or delivered hereunder to the holder of this Warrant shall
be in writing, and shall be personally delivered, or shall be sent by certified
or registered mail or by recognized overnight mail courier, postage prepaid and
addressed, to such holder at the address shown for such holder on the books of
the Company, or at such other address as shall have been furnished to the
Company by notice from such holder. All notices, requests, and other
communications required or permitted to be given or delivered hereunder to the
Company shall be in writing, and shall be personally delivered, or shall be sent
by certified or registered mail or by recognized overnight mail courier, postage
prepaid and addressed, to the office of the Company at 230 Constitution Drive,
Menlo Park, California 94025, Attn: David Greenwood, fax no. (650) 473-7701 with
copies to Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California
94025, Attn: Alan C. Mendelson, Esq., fax no. (650) 463-2600, or at such other
address as shall have been furnished to the holder of this Warrant by notice
from the Company. Any such notice, request, or other communication may be sent
by facsimile, but shall in such case be subsequently confirmed by a writing
personally delivered or sent by certified or registered mail or by recognized
overnight mail courier as provided above. All notices, requests, and other
communications shall be deemed to have been given either at the time of the
receipt thereof by the person entitled to receive such notice at the address of
such person for purposes of this Paragraph 8, or, if mailed by registered or
certified mail or with a recognized overnight mail courier upon deposit with the
United States Post Office or such overnight mail courier, if postage is prepaid
and the mailing is properly addressed, as the case may be.

<PAGE>

9. Governing Law. THIS WARRANT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAWS OF THE STATE OF DELAWARE APPLICABLE TO AGREEMENTS MADE AND TO BE
PERFORMED IN THE STATE OF DELAWARE (WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF
LAWS). BOTH PARTIES IRREVOCABLY CONSENT TO THE EXCLUSIVE JURISDICTION OF THE
UNITED STATES FEDERAL COURTS AND THE STATE COURTS LOCATED IN DELAWARE WITH
RESPECT TO ANY SUIT OR PROCEEDING BASED ON OR ARISING UNDER THIS AGREEMENT, THE
AGREEMENTS ENTERED INTO IN CONNECTION HEREWITH OR THE TRANSACTIONS CONTEMPLATED
HEREBY OR THEREBY AND IRREVOCABLY AGREE THAT ALL CLAIMS IN RESPECT OF SUCH SUIT
OR PROCEEDING MAY BE DETERMINED IN SUCH COURTS. BOTH PARTIES IRREVOCABLY WAIVE
THE DEFENSE OF AN INCONVENIENT FORUM TO THE MAINTENANCE OF SUCH SUIT OR
PROCEEDING. BOTH PARTIES FURTHER AGREE THAT SERVICE OF PROCESS UPON A PARTY
MAILED BY FIRST CLASS MAIL SHALL BE DEEMED IN EVERY RESPECT EFFECTIVE SERVICE OF
PROCESS UPON THE PARTY IN ANY SUCH SUIT OR PROCEEDING. NOTHING HEREIN SHALL
AFFECT EITHER PARTY'S RIGHT TO SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY
LAW. BOTH PARTIES AGREE THAT A FINAL NON-APPEALABLE JUDGMENT IN ANY SUCH SUIT OR
PROCEEDING SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY
SUIT ON SUCH JUDGMENT OR IN ANY OTHER LAWFUL MANNER.

10. Miscellaneous.

     (a) Amendments. This Warrant and any provision hereof may only be amended
by an instrument in writing signed by the Company and the Holder.

     (b) Descriptive Headings. The descriptive headings of the several
paragraphs of this Warrant are inserted for purposes of reference only, and
shall not affect the meaning or construction of any of the provisions hereof.

     (c) Remedies. The Company acknowledges that a breach by it of its
obligations hereunder will cause irreparable harm to the holder of this Warrant
by vitiating the intent and purpose of the transactions contemplated hereby.
Accordingly, the Company acknowledges that the remedy at law for a breach of its
obligations under this Warrant will be inadequate and agrees, in the event of a
breach or threatened breach by the Company of the provisions of this Warrant,
that the holder of this Warrant shall be entitled, in addition to all other
available remedies in law or in equity, to an injunction or injunctions to
prevent or cure any breaches of the provisions of this Agreement and to enforce
specifically the terms and provisions of this Warrant, without the necessity of
showing economic loss and without any bond or other security being required.

                [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officer.

                          GERON CORPORATION

                          By:   /s/ David L. Greenwood
                              -----------------------------------------------
                          Name: David L. Greenwood
                          Title: Executive Vice President and Chief Financial
                          Officer

                          Dated as of November __, 2004

<PAGE>

                           FORM OF EXERCISE AGREEMENT

                                                        Dated: ________ __, 200_

To:  GERON CORPORATION

         The undersigned, pursuant to the provisions set forth in the Warrant
attached hereto, hereby agrees to purchase ________ shares of Common Stock
covered by such Warrant, and makes payment herewith in full therefor at the
price per share provided by such Warrant in cash or by certified or official
bank check in the amount of $______. Please issue a certificate or certificates
for such shares of Common Stock in the name of and pay any cash for any
fractional share to:

                   Name:
                         -------------------------------------------------------

                   Signature:
                              --------------------------------------------------

                   Address:
                           -----------------------------------------------------

                   Note:   The above signature  should  correspond  exactly with
                           the name on the face of the Warrant attached hereto.

and, if said number of shares of Common Stock shall not be all the shares
purchasable under the Warrant attached hereto, a new Warrant is to be issued in
the name of said undersigned covering the balance of the shares purchasable
thereunder less any fraction of a share paid in cash.

<PAGE>

                               FORM OF ASSIGNMENT

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and
transfers all the rights of the undersigned under the Warrant attached hereto,
with respect to the number of shares of Common Stock covered thereby set forth
hereinbelow, to:

Name of Assignee             Address                  No of Shares
----------------             -------                  ------------

, and hereby irrevocably constitutes and appoints
____________________________________ as agent and attorney-in-fact to transfer
said Warrant on the books of the within-named corporation, with full power of
substitution in the premises.

Dated:  ________ __, 200_

In the presence of:

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

                       Name:
                            ----------------------------------------------------

                       Signature:
                                 -----------------------------------------------

                       Title of Signing Officer or Agent (if any):

                       Address:
                               -------------------------------------------------

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

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

                       Note: The above signature should correspond exactly
                       with the name on the face of the Warrant attached hereto.EXHIBIT C
                                                                     TO PURCHASE
                                                                       AGREEMENT

                                                                Right to
                                                                Purchase -------
                                                                Shares of
                                                                Common Stock,
                                                                par value $0.001
                                                                per share

                     FORM OF COMMON STOCK PURCHASE WARRANT C

     THIS CERTIFIES THAT, for value received, _____ or its registered assigns,
is entitled to purchase from Geron Corporation, a Delaware corporation (the
"Company"), at any time or from time to time during the period specified in
Paragraph 2 hereof, _____ fully paid and nonassessable shares of the Company's
common stock, par value $0.001 per share (the "Common Stock"), at an exercise
price of $0.01 per share (the "Exercise Price"). The term "Warrant Shares," as
used herein, refers to the shares of Common Stock purchasable hereunder. The
Warrant Shares are subject to adjustment as provided in Paragraph 4 hereof. The
term "Warrants" means this Warrant and the other warrants (including the A
Warrants and the B Warrants (each as defined in the Purchase Agreement)) issued
pursuant to that certain Securities Purchase Agreement, dated November 10, 2004,
by and among the Company and the Buyers listed on the execution page thereof
(the "Purchase Agreement").

         This Warrant is subject to the following terms, provisions, and
conditions:

1. Manner of Exercise; Issuance of Certificates; Payment for Warrant Shares. (a)
Subject to the provisions hereof, this Warrant may be exercised by the Holder,
in whole or in part, by the surrender of this Warrant, together with a completed
exercise agreement in the form attached hereto (the "Exercise Agreement"), to
the Company during normal business hours on any business day at the Company's
principal executive offices (or such other office or agency of the Company as it
may designate by notice to the Holder), and upon payment to the Company in cash,
by certified or official bank check or by wire transfer for the account of the
Company of the Exercise Price for the Warrant Shares specified in the Exercise
Agreement. The Warrant Shares so purchased shall be deemed to be issued to the
Holder or such holder's designee, as the record owner of such shares, as of the
close of business on the date on which this Warrant shall have been surrendered,
the completed Exercise Agreement shall have been delivered, and payment shall
have been made for such shares as set forth above. In the event of any exercise
of the rights represented by this Warrant in accordance with and subject to the
terms and conditions hereof, the Warrant Shares shall be issued and delivered to
the Depository Trust Company account on the Holder's behalf via the Deposit
Withdrawal Agent Commission system ("DWAC Transfer") within a reasonable time,
not exceeding two (2) trading days after such exercise (or, if DWAC Transfer is

<PAGE>

not available or Holder otherwise requests in writing, certificates for the
Warrant Shares shall be issued, dated the date of such exercise and delivered to
the Holder hereof within a reasonable time, not exceeding three (3) trading days
after such exercise), and the Holder hereof shall be deemed for all purposes to
be the holder of the Warrant Shares so purchased as of the date of such
exercise. Any certificates requested shall be delivered in such denominations as
may be requested by the Holder and shall be registered in the name of such
holder or such other name as shall be designated by such holder. If this Warrant
shall have been exercised only in part, then, unless this Warrant has expired,
the Company shall, at its expense, at the time of delivery of such certificates,
deliver to the holder a new Warrant representing the number of shares with
respect to which this Warrant shall not then have been exercised. In the event
an Exercise Agreement is delivered and the Company is unable to issue the
Warrant Shares, the Holder may, at its option, rescind such Exercise Agreement
and such rescission will not effect the Holder's right to an extension of the
Exercise Period pursuant to Section 4.13 of the Purchase Agreement.

         (b) Notwithstanding anything in this Warrant to the contrary, in no
event shall the Holder of this Warrant be entitled to exercise a number of
Warrants (or portions thereof) in excess of the number of Warrants (or portions
thereof) upon exercise of which the sum of (i) the number of shares of Common
Stock beneficially owned by the Holder and its affiliates (other than shares of
Common Stock which, but for this proviso, may be deemed beneficially owned
through the ownership of the unexercised Warrants and the unexercised or
unconverted portion of any other securities of the Company subject to a
limitation on conversion or exercise analogous to the limitation contained
herein) and (ii) the number of shares of Common Stock issuable upon exercise of
the Warrants (or portions thereof) with respect to which the determination
described herein is being made, would result in beneficial ownership by the
Holder and its affiliates of more than 4.9% of the outstanding shares of Common
Stock. For purposes of the immediately preceding sentence, beneficial ownership
shall be determined in accordance with Section 13(d) of the Securities Exchange
Act of 1934, as amended, and Regulations 13D-G thereunder, except as otherwise
provided in clause (i) hereof. Notwithstanding anything in this Warrant to the
contrary, the restrictions on exercise of this Warrant set forth in this
paragraph shall not be amended without (i) the written consent of the Holder and
the Company and (ii) the approval of the holders of a majority of the Common
Stock present, or represented by proxy, and voting at any meeting called to vote
on the amendment of such restriction.

     2. Period of Exercise. This Warrant is exercisable at any time or from time
to time on or after the date on which this Warrant is issued and delivered
pursuant to the terms of the Purchase Agreement (the "Issue Date") before 8:00
p.m., New York City time on the second (2nd) anniversary of the Issue Date (the
"Exercise Period"); provided, however, that the Exercise Period will be extended
in accordance with Section 4.13 of the Purchase Agreement upon the occurrence of
events set forth in such section.

     3. Certain Agreements of the Company. The Company hereby covenants and
agrees as follows:

     (a) Shares to be Fully Paid. All Warrant Shares will, upon issuance in
accordance with the terms of this Warrant, be validly issued, fully paid, and
nonassessable and free from all taxes, liens, and charges with respect to the
issue thereof.

<PAGE>

     (b) Reservation of Shares. During the Exercise Period, the Company shall at
all times have authorized, and reserved for the purpose of issuance upon
exercise of this Warrant, a sufficient number of shares of Common Stock to
provide for the full exercise of this Warrant.

     (c) Listing. The Company shall promptly secure the listing of the Warrant
Shares upon each national securities exchange or automated quotation system, if
any, upon which shares of Common Stock are then listed (subject to official
notice of issuance upon exercise of this Warrant) and shall maintain, so long as
any other shares of Common Stock shall be so listed, such listing of all Warrant
Shares; and the Company shall so list on each national securities exchange or
automated quotation system, as the case may be, and shall maintain such listing
of, any other shares of capital stock of the Company issuable upon the exercise
of this Warrant if and so long as any shares of the same class shall be listed
on such national securities exchange or automated quotation system.

     (d) Certain Actions Prohibited. The Company will not, by amendment of its
charter or through any reorganization, transfer of assets, consolidation,
merger, dissolution, issue or sale of securities, or any other voluntary action,
avoid or seek to avoid the observance or performance of any of the terms to be
observed or performed by it hereunder, but will at all times in good faith
assist in the carrying out of all the provisions of this Warrant and in the
taking of all such action as may reasonably be requested by the holder of this
Warrant in order to protect the exercise privilege of the holder of this Warrant
against dilution or other impairment, consistent with the tenor and purpose of
this Warrant. Without limiting the generality of the foregoing, the Company (i)
will not increase the par value of any shares of Common Stock receivable upon
the exercise of this Warrant above the Exercise Price then in effect, and (ii)
will take all such actions as may be necessary or appropriate in order that the
Company may validly and legally issue fully paid and nonassessable shares of
Common Stock upon the exercise of this Warrant.

     (e) Successors and Assigns. This Warrant will be binding upon any entity
succeeding to the Company by merger, consolidation, or acquisition of all or
substantially all the Company's assets.

     4. Antidilution Provisions. During the Exercise Period, the number of
Warrant Shares shall be subject to adjustment from time to time as provided in
this Paragraph 4.

     (a) Subdivision or Combination of Common Stock. If the Company at any time
subdivides (by any stock split, stock dividend, recapitalization,
reorganization, reclassification or otherwise) the shares of Common Stock
acquirable hereunder into a greater number of shares, then, after the date of
record for effecting such subdivision, the number of shares of Common Stock
issuable upon exercise of this Warrant prior to such subdivision will be
increased accordingly. If the Company at any time combines (by reverse stock
split, recapitalization, reorganization, reclassification or otherwise) the
shares of Common Stock acquirable hereunder into a smaller number of shares,
then, after the date of record for effecting such combination, the number of
shares of Common Stock issuable upon exercise of this Warrant prior to such
subdivision will be decreased accordingly. "Common Stock," for purposes of this
Paragraph 4, includes the Common Stock, par value $0.001 per share, and any
additional class of stock of the Company having no preference as to dividends or
distributions on liquidation, provided that the shares purchasable pursuant to
this Warrant shall include only shares of Common Stock, par value $0.001 per

<PAGE>

share, in respect of which this Warrant is exercisable, or shares resulting from
any subdivision or combination of such Common Stock, or in the case of any
reorganization, reclassification, consolidation, merger, or sale of the
character referred to in Paragraph 4(c) hereof, the stock or other securities or
property provided for in such Paragraph.

     (b) Consolidation, Merger or Sale. In case of any consolidation of the
Company with, or merger of the Company into any other corporation, or in case of
any sale or conveyance of all or substantially all of the assets of the Company
other than in connection with a plan of complete liquidation of the Company,
then as a condition of such consolidation, merger or sale or conveyance,
adequate provision will be made whereby the holder of this Warrant will have the
right to acquire and receive upon exercise of this Warrant in lieu of the shares
of Common Stock immediately theretofore acquirable upon the exercise of this
Warrant, such shares of stock, securities or assets as may be issued or payable
with respect to or in exchange for the number of shares of Common Stock
immediately theretofore acquirable and receivable upon exercise of this Warrant
had such consolidation, merger or sale or conveyance not taken place. In any
such case, the Company will make appropriate provision to insure that the
provisions of this Paragraph 4 hereof will thereafter be applicable as nearly as
may be in relation to any shares of stock or securities thereafter deliverable
upon the exercise of this Warrant. The Company will not effect any
consolidation, merger or sale or conveyance unless prior to the consummation
thereof, the successor or acquiring entity (if other than the Company) and, if
an entity different from the successor or acquiring entity, the entity whose
capital stock or assets the holders of the Common Stock of the Company are
entitled to receive as a result of such consolidation, merger or sale or
conveyance assumes by written instrument the obligations under this Paragraph 4
and the obligations to deliver to the holder of this Warrant such shares of
stock, securities or assets as, in accordance with the foregoing provisions, the
holder may be entitled to acquire.

     (c) Distribution of Assets. In case the Company shall declare or make any
distribution of its assets (including cash) to holders of Common Stock as a
partial liquidating dividend, by way of return of capital or otherwise, then,
after the date of record for determining stockholders entitled to such
distribution, but prior to the date of distribution, the holder of this Warrant
shall be entitled upon exercise of this Warrant for the purchase of any or all
of the shares of Common Stock subject hereto, to receive the amount of such
assets which would have been payable to the holder had such holder been the
holder of such shares of Common Stock on the record date for the determination
of stockholders entitled to such distribution.

     (d) Notice of Adjustment. Upon the occurrence of any event which requires
any adjustment of the Exercise Price, then, and in each such case, the Company
shall give notice thereof to the holder of this Warrant, which notice shall
state the Exercise Price resulting from such adjustment and the increase or
decrease in the number of Warrant Shares purchasable at such price upon
exercise, setting forth in reasonable detail the method of calculation and the
facts upon which such calculation is based. Such calculation shall be certified
by the chief financial officer of the Company.

     (e) Minimum Adjustment of Exercise Price. No adjustment of the Exercise
Price shall be made in an amount of less than 1% of the Exercise Price in effect
at the time such adjustment is otherwise required to be made, but any such
lesser adjustment shall be carried forward and shall be made at the time and
together with the next subsequent adjustment which, together with any
adjustments so carried forward, shall amount to not less than 1% of such
Exercise Price.

<PAGE>

     (f) No Fractional Shares. No fractional shares of Common Stock are to be
issued upon the exercise of this Warrant. If the exercise of this Warrant would
result in a fractional share of Common Stock, such fractional share shall be
disregarded and the number of shares of Common Stock issuable upon exercise of
the Warrant shall be the next higher number of shares.

     (g) Other Notices. In case at any time:

     (i) the Company shall declare any dividend upon the Common Stock payable in
shares of stock of any class or make any other distribution (including dividends
or distributions payable in cash out of retained earnings) to the holders of the
Common Stock;

     (ii) the Company shall offer for subscription pro rata to the holders of
the Common Stock any additional shares of stock of any class or other rights;

     (iii) there shall be any capital reorganization of the Company, or
reclassification of the Common Stock, or consolidation or merger of the Company
with or into, or sale of all or substantially all its assets to, another
corporation or entity; or

     (iv) there shall be a voluntary or involuntary dissolution, liquidation or
winding-up of the Company;

then, in each such case, the Company shall give to the holder of this Warrant
(a) notice of the date on which the books of the Company shall close or a record
shall be taken for determining the holders of Common Stock entitled to receive
any such dividend, distribution, or subscription rights or for determining the
holders of Common Stock entitled to vote in respect of any such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation or
winding-up and (b) in the case of any such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation or winding-up, notice of
the date (or, if not then known, a reasonable approximation thereof by the
Company) when the same shall take place. Such notice shall also specify the date
on which the holders of Common Stock shall be entitled to receive such dividend,
distribution, or subscription rights or to exchange their Common Stock for stock
or other securities or property deliverable upon such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation, or
winding-up, as the case may be. Such notice shall be given at least 30 days
prior to the record date or the date on which the Company's books are closed in
respect thereto. Failure to give any such notice or any defect therein shall not
affect the validity of the proceedings referred to in clauses (i), (ii), (iii)
and (iv) above.

     (h) Certain Events. If any event occurs of the type contemplated by the
adjustment provisions of this Paragraph 4 but not expressly provided for by such
provisions, the Company will give notice of such event as provided in Paragraph
4(e) hereof, and the Company's Board of Directors will make an appropriate
adjustment in the Exercise Price and the number of shares of Common Stock
acquirable upon exercise of this Warrant so that the rights of the Holder shall
be neither enhanced nor diminished by such event.

<PAGE>

     5. Issue Tax. The issuance of certificates for Warrant Shares upon the
exercise of this Warrant shall be made without charge to the holder of this
Warrant or such shares for any issuance tax or other costs in respect thereof,
provided that the Company shall not be required to pay any tax which may be
payable in respect of any transfer involved in the issuance and delivery of any
certificate in a name other than the holder of this Warrant.

     6. No Rights or Liabilities as a Stockholder. This Warrant shall not
entitle the Holder to any voting rights, dividend rights or other rights as a
stockholder of the Company. No provision of this Warrant, in the absence of
affirmative action by the Holder to purchase Warrant Shares, and no mere
enumeration herein of the rights or privileges of the Holder, shall give rise to
any liability of such holder for the Exercise Price or as a stockholder of the
Company, whether such liability is asserted by the Company or by creditors of
the Company.

     7. Transfer, Exchange, and Replacement of Warrant.

     (a) Transfer. This Warrant and the rights granted to the Holder are
transferable, in whole or in part, upon surrender of this Warrant, together with
a properly executed assignment in the form attached hereto, at the office or
agency of the Company referred to in Paragraph 7(e) below. Until due presentment
for registration of transfer on the books of the Company, the Company may treat
the registered Holder as the owner and Holder for all purposes, and the Company
shall not be affected by any notice to the contrary.

     (b) Warrant Exchangeable for Different Denominations. This Warrant is
exchangeable, upon the surrender hereof by the Holder at the office or agency of
the Company referred to in Paragraph 7(e) below, for new Warrants of like tenor
representing in the aggregate the right to purchase the number of shares of
Common Stock which may be purchased hereunder, each of such new Warrants to
represent the right to purchase such number of shares as shall be designated by
the Holder at the time of such surrender.

     (c) Replacement of Warrant. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction, or mutilation of
this Warrant and, in the case of any such loss, theft, or destruction, upon
delivery of an indemnity agreement reasonably satisfactory in form and amount to
the Company, or, in the case of any such mutilation, upon surrender and
cancellation of this Warrant, the Company, at its expense, will execute and
deliver, in lieu thereof, a new Warrant of like tenor.

     (d) Cancellation; Payment of Expenses. Upon the surrender of this Warrant
in connection with any transfer, exchange, or replacement as provided in this
Paragraph 7, this Warrant shall be promptly canceled by the Company. The Company
shall pay all taxes (other than securities transfer taxes) and all other
expenses (other than legal expenses, if any, incurred by the Holder or
transferees) and charges payable in connection with the preparation, execution,
and delivery of Warrants pursuant to this Paragraph 7.

     (e) Register. The Company shall maintain, at its principal executive
offices (or such other office or agency of the Company as it may designate by
notice to the Holder), a register for this Warrant, in which the Company shall
record the name and address of the person in whose name this Warrant has been
issued, as well as the name and address of each transferee and each prior owner
of this Warrant.

<PAGE>

     8. Notices. All notices, requests, and other communications required or
permitted to be given or delivered hereunder to the holder of this Warrant shall
be in writing, and shall be personally delivered, or shall be sent by certified
or registered mail or by recognized overnight mail courier, postage prepaid and
addressed, to such holder at the address shown for such holder on the books of
the Company, or at such other address as shall have been furnished to the
Company by notice from such holder. All notices, requests, and other
communications required or permitted to be given or delivered hereunder to the
Company shall be in writing, and shall be personally delivered, or shall be sent
by certified or registered mail or by recognized overnight mail courier, postage
prepaid and addressed, to the office of the Company at 230 Constitution Drive,
Menlo Park, California 94025, Attn: David Greenwood, fax no. (650) 473-7701 with
copies to Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California
94025, Attn: Alan C. Mendelson, Esq., fax no. (650) 463-2600, or at such other
address as shall have been furnished to the holder of this Warrant by notice
from the Company. Any such notice, request, or other communication may be sent
by facsimile, but shall in such case be subsequently confirmed by a writing
personally delivered or sent by certified or registered mail or by recognized
overnight mail courier as provided above. All notices, requests, and other
communications shall be deemed to have been given either at the time of the
receipt thereof by the person entitled to receive such notice at the address of
such person for purposes of this Paragraph 8, or, if mailed by registered or
certified mail or with a recognized overnight mail courier upon deposit with the
United States Post Office or such overnight mail courier, if postage is prepaid
and the mailing is properly addressed, as the case may be.

     9. Governing Law. THIS WARRANT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE APPLICABLE TO AGREEMENTS MADE
AND TO BE PERFORMED IN THE STATE OF DELAWARE (WITHOUT REGARD TO PRINCIPLES OF
CONFLICT OF LAWS). BOTH PARTIES IRREVOCABLY CONSENT TO THE EXCLUSIVE
JURISDICTION OF THE UNITED STATES FEDERAL COURTS AND THE STATE COURTS LOCATED IN
DELAWARE WITH RESPECT TO ANY SUIT OR PROCEEDING BASED ON OR ARISING UNDER THIS
AGREEMENT, THE AGREEMENTS ENTERED INTO IN CONNECTION HEREWITH OR THE
TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY AND IRREVOCABLY AGREE THAT ALL
CLAIMS IN RESPECT OF SUCH SUIT OR PROCEEDING MAY BE DETERMINED IN SUCH COURTS.
BOTH PARTIES IRREVOCABLY WAIVE THE DEFENSE OF AN INCONVENIENT FORUM TO THE
MAINTENANCE OF SUCH SUIT OR PROCEEDING. BOTH PARTIES FURTHER AGREE THAT SERVICE
OF PROCESS UPON A PARTY MAILED BY FIRST CLASS MAIL SHALL BE DEEMED IN EVERY
RESPECT EFFECTIVE SERVICE OF PROCESS UPON THE PARTY IN ANY SUCH SUIT OR
PROCEEDING. NOTHING HEREIN SHALL AFFECT EITHER PARTY'S RIGHT TO SERVE PROCESS IN
ANY OTHER MANNER PERMITTED BY LAW. BOTH PARTIES AGREE THAT A FINAL
NON-APPEALABLE JUDGMENT IN ANY SUCH SUIT OR PROCEEDING SHALL BE CONCLUSIVE AND
MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON SUCH JUDGMENT OR IN ANY OTHER
LAWFUL MANNER.

<PAGE>

10. Miscellaneous.

     (a) Amendments. This Warrant and any provision hereof may only be amended
by an instrument in writing signed by the Company and the Holder.

     (b) Descriptive Headings. The descriptive headings of the several
paragraphs of this Warrant are inserted for purposes of reference only, and
shall not affect the meaning or construction of any of the provisions hereof.

     (c) Remedies. The Company acknowledges that a breach by it of its
obligations hereunder will cause irreparable harm to the holder of this Warrant
by vitiating the intent and purpose of the transactions contemplated hereby.
Accordingly, the Company acknowledges that the remedy at law for a breach of its
obligations under this Warrant will be inadequate and agrees, in the event of a
breach or threatened breach by the Company of the provisions of this Warrant,
that the holder of this Warrant shall be entitled, in addition to all other
available remedies in law or in equity, to an injunction or injunctions to
prevent or cure any breaches of the provisions of this Agreement and to enforce
specifically the terms and provisions of this Warrant, without the necessity of
showing economic loss and without any bond or other security being required.

                [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officer.

                          GERON CORPORATION

                          By: /s/ David L. Greenwood
                              -----------------------------------------------
                          Name: David L. Greenwood
                          Title: Executive Vice President and Chief Financial
                          Officer

                          Dated as of November __, 2004

<PAGE>

                           FORM OF EXERCISE AGREEMENT

                                                        Dated: ________ __, 200_

To:  GERON CORPORATION

         The undersigned, pursuant to the provisions set forth in the Warrant
attached hereto, hereby agrees to purchase ________ shares of Common Stock
covered by such Warrant, and makes payment herewith in full therefor at the
price per share provided by such Warrant in cash or by certified or official
bank check in the amount of $_________. Please issue a certificate or
certificates for such shares of Common Stock in the name of and pay any cash for
any fractional share to:

                      Name:

                      Signature:
                                  ----------------------------------------------

                      Address:
                                  ----------------------------------------------

                      Note: The above signature should correspond exactly with
                            the name on the face of the Warrant attached hereto.

and, if said number of shares of Common Stock shall not be all the shares
purchasable under the Warrant attached hereto, a new Warrant is to be issued in
the name of said undersigned covering the balance of the shares purchasable
thereunder less any fraction of a share paid in cash.

<PAGE>

                               FORM OF ASSIGNMENT

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and
transfers all the rights of the undersigned under the Warrant attached hereto,
with respect to the number of shares of Common Stock covered thereby set forth
hereinbelow, to:

Name of Assignee           Address               No of Shares
----------------           -------               ------------

, and hereby irrevocably constitutes and appoints
______________________________________ as agent and attorney-in-fact to transfer
said Warrant on the books of the within-named corporation, with full power of
substitution in the premises.

Dated:  ________ __, 200_

In the presence of:

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

                    Name:
                         -------------------------------------------------------

                    Signature:
                              --------------------------------------------------

                    Title of Signing Officer or Agent (if any):

                    Address:
                            ----------------------------------------------------

                    Note:  The above signature should correspond exactly
                    with the name on the face of the Warrant attached hereto.

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

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00074-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00074-of-00352.parquet"}]]