EXHIBIT
4.6 

Geron Corporation


AND

_____________, As Warrant
Agent 

Form Of Preferred Stock
Warrant Agreement 

Dated As Of __________








GERON CORPORATION


FORM OF PREFERRED STOCK
WARRANT AGREEMENT 

This Preferred
Stock Warrant Agreement (this
“Agreement”), dated as of [●], between GERON CORPORATION, a Delaware
corporation (the “Company”) and [●], a
[corporation] [national banking association] organized and existing under the
laws of [●] and having a corporate trust office in [●], as warrant agent (the
“Warrant
Agent”). 

Whereas, the Company proposes to sell [If Warrants are sold with other securities —
[title of such other
securities being offered] (the “Other Securities”)
with] warrant certificates evidencing one or more warrants (the
“Warrants” or, individually, a “Warrant”) representing the right to purchase [title of Preferred Stock
purchasable through exercise of Warrants] (the “Warrant Securities”), such warrant certificates and other warrant
certificates issued pursuant to this Agreement being herein called the
“Warrant
Certificates”; and


Whereas, the Company desires the Warrant Agent to act on
behalf of the Company, and the Warrant Agent is willing so to act, in connection
with the issuance, registration, transfer, exchange, exercise and replacement of
the Warrant Certificates, and in this Agreement wishes to set forth, among other
things, the form and provisions of the Warrant Certificates and the terms and
conditions on which they may be issued, registered, transferred, exchanged,
exercised and replaced. 

Now Therefore, in consideration
of the premises and of the mutual agreements herein contained, the parties
hereto agree as follows: 

ARTICLE 1 

ISSUANCE OF WARRANTS AND
EXECUTION AND
DELIVERY OF WARRANT CERTIFICATES 

1.1 Issuance Of Warrants. [If Warrants alone
—Upon issuance, each Warrant Certificate shall evidence one or more Warrants.]
[If Other Securities and
Warrants —Warrant
Certificates will be issued in connection with the issuance of the Other
Securities but shall be separately transferable and each Warrant Certificate
shall evidence one or more Warrants.] Each Warrant evidenced thereby shall
represent the right, subject to the provisions contained herein and therein, to
purchase one Warrant Security. [If Other Securities and Warrants —Warrant Certificates will be issued with the
Other Securities and each Warrant Certificate will evidence [●] Warrants for
each [$[●] principal amount] [[●] shares] of Other Securities issued.]


1.2 Execution And Delivery Of Warrant
Certificates. Each Warrant
Certificate, whenever issued, shall be in registered form substantially in the
form set forth in Exhibit
A hereto, shall be dated the date
of its countersignature by the Warrant Agent and may have such letters, numbers,
or other marks of identification or designation and such legends or endorsements
printed, lithographed or engraved thereon as the officers of the Company
executing the same may approve (execution thereof to be conclusive evidence of
such approval) and as are not inconsistent with the provisions of this
Agreement, or as may be required to comply with any law or with any rule or
regulation made pursuant thereto or with any rule or regulation of any
securities exchange on which the Warrants may be listed, or to conform to usage.
The Warrant Certificates shall be signed on behalf of the Company by any of its
present or future chief executive officers, presidents, senior vice presidents,
vice presidents, chief financial officers, chief legal officers, treasurers,
assistant treasurers, controllers, assistant controllers, secretaries or
assistant secretaries under its corporate seal reproduced thereon. Such
signatures may be manual or facsimile signatures of such authorized officers and
may be imprinted or otherwise reproduced on the Warrant Certificates. The seal
of the Company may be in the form of a facsimile thereof and may be impressed,
affixed, imprinted or otherwise reproduced on the Warrant Certificates.


1







No Warrant Certificate shall be valid for any purpose, and no Warrant
evidenced thereby shall be exercisable, until such Warrant Certificate has been
countersigned by the manual signature of the Warrant Agent. Such signature by
the Warrant Agent upon any Warrant Certificate executed by the Company shall be
conclusive evidence that the Warrant Certificate so countersigned has been duly
issued hereunder. 

In case any officer of the Company who shall have signed any of the
Warrant Certificates either manually or by facsimile signature shall cease to be
such officer before the Warrant Certificates so signed shall have been
countersigned and delivered by the Warrant Agent, such Warrant Certificates may
be countersigned and delivered notwithstanding that the person who signed such
Warrant Certificates ceased to be such officer of the Company; and any Warrant
Certificate may be signed on behalf of the Company by such persons as, at the
actual date of the execution of such Warrant Certificate, shall be the proper
officers of the Company, although at the date of the execution of this Agreement
any such person was not such officer. 

The term “holder” or
“holder of a Warrant
Certificate” as used herein
shall mean any person in whose name at the time any Warrant Certificate shall be
registered upon the books to be maintained by the Warrant Agent for that
purpose.

1.3 Issuance Of Warrant Certificates. Warrant Certificates evidencing the right to
purchase Warrant Securities may be executed by the Company and delivered to the
Warrant Agent upon the execution of this Warrant Agreement or from time to time
thereafter. The Warrant Agent shall, upon receipt of Warrant Certificates duly
executed on behalf of the Company, countersign such Warrant Certificates and
shall deliver such Warrant Certificates to or upon the order of the Company.


ARTICLE 2 

WARRANT PRICE, DURATION
AND EXERCISE OF WARRANTS


2.1 Warrant Price. During the period specified in Section 2.2, each
Warrant shall, subject to the terms of this Warrant Agreement and the applicable
Warrant Certificate, entitle the holder thereof to purchase the number of
Warrant Securities specified in the applicable Warrant Certificate at an
exercise price of $[●] per Warrant Security, subject to adjustment upon the
occurrence of certain events, as hereinafter provided. Such purchase price per
Warrant Security is referred to in this Agreement as the “Warrant Price.” 

2.2 Duration Of Warrants. Each Warrant may be exercised in whole or in
part at any time, as specified herein, on or after [the date thereof] [●] and at
or before [●] p.m., [City] time, on [●] or such later date as the Company may
designate by notice to the Warrant Agent and the holders of Warrant Certificates
mailed to their addresses as set forth in the record books of the Warrant Agent
(the “Expiration
Date”). Each Warrant not
exercised at or before [●] p.m., [City] time, on the Expiration Date shall
become void, and all rights of the holder of the Warrant Certificate evidencing
such Warrant under this Agreement shall cease. 

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2.3 Exercise Of Warrants. 

(a) During the period specified in Section 2.2, the
Warrants may be exercised to purchase a whole number of Warrant Securities in
registered form by providing certain information as set forth on the reverse
side of the Warrant Certificate and by paying in full, in lawful money of the
United States of America, [in cash or by certified check or official bank check
in New York Clearing House funds] [by bank wire transfer in immediately
available funds] the Warrant Price for each Warrant Security with respect to
which a Warrant is being exercised to the Warrant Agent at its corporate trust
office, provided that such exercise is subject to receipt within five business
days of such payment by the Warrant Agent of the Warrant Certificate with the
form of election to purchase Warrant Securities set forth on the reverse side of
the Warrant Certificate properly completed and duly executed. The date on which
payment in full of the Warrant Price is received by the Warrant Agent shall,
subject to receipt of the Warrant Certificate as aforesaid, be deemed to be the
date on which the Warrant is exercised; provided, however, that if, at the date
of receipt of such Warrant Certificates and payment in full of the Warrant
Price, the transfer books for the Warrant Securities purchasable upon the
exercise of such Warrants shall be closed, no such receipt of such Warrant
Certificates and no such payment of such Warrant Price shall be effective to
constitute the person so designated to be named as the holder of record of such
Warrant Securities on such date, but shall be effective to constitute such
person as the holder of record of such Warrant Securities for all purposes at
the opening of business on the next succeeding day on which the transfer books
for the Warrant Securities purchasable upon the exercise of such Warrants shall
be opened, and the certificates for the Warrant Securities in respect of which
such Warrants are then exercised shall be issuable as of the date on such next
succeeding day on which the transfer books shall next be opened, and until such
date the Company shall be under no duty to deliver any certificate for such
Warrant Securities. The Warrant Agent shall deposit all funds received by it in
payment of the Warrant Price in an account of the Company maintained with it and
shall advise the Company by telephone at the end of each day on which a payment
for the exercise of Warrants is received of the amount so deposited to its
account. The Warrant Agent shall promptly confirm such telephone advice to the
Company in writing. 

(b) The Warrant Agent shall, from time to time, as
promptly as practicable, advise the Company of (i) the number of Warrant
Securities with respect to which Warrants were exercised, (ii) the instructions
of each holder of the Warrant Certificates evidencing such Warrants with respect
to delivery of the Warrant Securities to which such holder is entitled upon such
exercise, (iii) delivery of Warrant Certificates evidencing the balance, if any,
of the Warrants for the remaining Warrant Securities after such exercise, and
(iv) such other information as the Company shall reasonably require. 

(c) As soon as practicable after the exercise of any
Warrant, the Company shall issue to or upon the order of the holder of the
Warrant Certificate evidencing such Warrant, the Warrant Securities to which
such holder is entitled, in fully registered form, registered in such name or
names as may be directed by such holder. If fewer than all of the Warrants
evidenced by such Warrant Certificate are exercised, the Company shall execute,
and an authorized officer of the Warrant Agent shall manually countersign and
deliver, a new Warrant Certificate evidencing Warrants for the number of Warrant
Securities remaining unexercised. 

(d) The Company shall not be required to pay any stamp
or other tax or other governmental charge required to be paid in connection with
any transfer involved in the issue of the Warrant Securities, and in the event
that any such transfer is involved, the Company shall not be required to issue
or deliver any Warrant Security until such tax or other charge shall have been
paid or it has been established to the Company’s satisfaction that no such tax
or other charge is due. 

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(e) Prior to the issuance of any Warrants there shall
have been reserved, and the Company shall at all times through the Expiration
Date keep reserved, out of its authorized but unissued Warrant Securities, a
number of shares sufficient to provide for the exercise of the Warrants.


ARTICLE 3 

OTHER PROVISIONS RELATING
TO RIGHTS OF HOLDERS OF
WARRANT CERTIFICATES 

3.1 No Rights As Warrant Securityholder Conferred By
Warrants Or Warrant Certificates.
No Warrant Certificate or Warrant evidenced thereby shall entitle the holder
thereof to any of the rights of a holder of Warrant Securities, including,
without limitation, the right to receive the payment of dividends or
distributions, if any, on the Warrant Securities or to exercise any voting
rights, except to the extent expressly set forth in this Agreement or the
applicable Warrant Certificate. 

3.2 Lost, Stolen, Mutilated Or Destroyed Warrant
Certificates. Upon receipt by the
Warrant Agent of evidence reasonably satisfactory to it and the Company of the
ownership of and the loss, theft, destruction or mutilation of any Warrant
Certificate and/or indemnity reasonably satisfactory to the Warrant Agent and
the Company and, in the case of mutilation, upon surrender of the mutilated
Warrant Certificate to the Warrant Agent for cancellation, then, in the absence
of notice to the Company or the Warrant Agent that such Warrant Certificate has
been acquired by a bona fide purchaser, the Company shall execute, and an
authorized officer of the Warrant Agent shall manually countersign and deliver,
in exchange for or in lieu of the lost, stolen, destroyed or mutilated Warrant
Certificate, a new Warrant Certificate of the same tenor and evidencing Warrants
for a like number of Warrant Securities. Upon the issuance of any new Warrant
Certificate under this Section 3.2, the Company may require the payment of a sum
sufficient to cover any tax or other governmental charge that may be imposed in
relation thereto and any other expenses (including the fees and expenses of the
Warrant Agent) in connection therewith. Every substitute Warrant Certificate
executed and delivered pursuant to this Section 3.2 in lieu of any lost, stolen
or destroyed Warrant Certificate shall represent an additional contractual
obligation of the Company, whether or not the lost, stolen or destroyed Warrant
Certificate shall be at any time enforceable by anyone, and shall be entitled to
the benefits of this Agreement equally and proportionately with any and all
other Warrant Certificates duly executed and delivered hereunder. The provisions
of this Section 3.2 are exclusive and shall preclude (to the extent lawful) all
other rights and remedies with respect to the replacement of mutilated, lost,
stolen or destroyed Warrant Certificates. 

3.3 Holder Of Warrant Certificate May Enforce
Rights. Notwithstanding any of
the provisions of this Agreement, any holder of a Warrant Certificate, without
the consent of the Warrant Agent, the holder of any Warrant Securities or the
holder of any other Warrant Certificate, may, in such holder’s own behalf and
for such holder’s own benefit, enforce, and may institute and maintain any suit,
action or proceeding against the Company suitable to enforce, or otherwise in
respect of, such holder’s right to exercise the Warrants evidenced by such
holder’s Warrant Certificate in the manner provided in such holder’s Warrant
Certificate and in this Agreement. 

3.4 Adjustments. 

(a) In case the Company shall at any time subdivide
its outstanding shares of [title of Preferred Stock purchasable through exercise
of Warrants] into a greater number of shares, the Warrant Price in effect
immediately prior to such subdivision shall be proportionately reduced and the
number of Warrant Securities purchasable under the Warrants shall be
proportionately increased. Conversely, in case the outstanding shares of [title
of Preferred Stock purchasable through exercise of Warrants] of the Company
shall be combined into a smaller number of shares, the Warrant Price in effect
immediately prior to such combination shall be proportionately increased and the
number of Warrant Securities purchasable under the Warrants shall be
proportionately decreased. 

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(b) If at any time or from time to time the holders of
[title of Preferred Stock purchasable through exercise of Warrants] (or any
shares of stock or other securities at the time receivable upon the exercise of
the Warrants) shall have received or become entitled to receive, without payment
therefore, 

(i) [title of Preferred Stock purchasable through
exercise of Warrants] or any shares of stock or other securities which are at
any time directly or indirectly convertible into or exchangeable for [title of
Preferred Stock purchasable through exercise of Warrants], or any rights or
options to subscribe for, purchase or otherwise acquire any of the foregoing by
way of dividend or other distribution; 

(ii) any cash paid or payable otherwise than in
accordance with the terms of [title of Preferred Stock purchasable through
exercise of Warrants] or otherwise than as a cash dividend paid or payable out
of the Company’s current or retained earnings; 

(iii) any evidence of the Company’s indebtedness or
rights to subscribe for or purchase the Company’s indebtedness; or 

(iv) [title of Preferred Stock purchasable through
exercise of Warrants] or additional stock or other securities or property
(including cash) by way of spinoff, split-up, reclassification, combination of
shares or similar corporate rearrangement (other than shares of [title of
Preferred Stock purchasable through exercise of Warrants] issued as a stock
split or adjustments in respect of which shall be covered by the terms of
Section 3.4(a) above), then and in each such case, the holder of each Warrant
shall, upon the exercise of the Warrant, be entitled to receive, in addition to
the number of Warrant Securities receivable thereupon, and without payment of
any additional consideration therefore, the amount of stock and other securities
and property (including cash and indebtedness or rights to subscribe for or
purchase indebtedness) which such holder would hold on the date of such exercise
had he been the holder of record of such Warrant Securities as of the date on
which holders of [title of Preferred Stock purchasable through exercise of
Warrants] received or became entitled to receive such shares or all other
additional stock and other securities and property. 

(c) In case of (i) any reclassification, capital
reorganization, or change in the [title of Preferred Stock purchasable through
the exercise of the Warrants] of the Company (other than as a result of a
subdivision, combination or stock dividend provided for in Section 3.4(a) or
Section 3.4(b) above), (ii) share exchange, merger or similar transaction of the
Company with or into another person or entity (other than a share exchange,
merger or similar transaction in which the Company is the acquiring or surviving
corporation and which does not result in any change in the [title of Preferred
Stock purchasable through the exercise of the Warrants] other than the issuance
of additional shares of [title of Preferred Stock purchasable through the
exercise of the Warrants]) or (iii) the sale, exchange, lease, transfer or other
disposition of all or substantially all of the properties and assets of the
Company as an entirety (in any such case, a “Reorganization Event”), then, as a condition of such Reorganization
Event, lawful provisions shall be made, and duly executed documents evidencing
the same from the Company or its successor shall be delivered to the holders of
the Warrants, so that the holders of the Warrants shall have the right at any
time prior to the expiration of the Warrants to purchase, at a total price equal
to that payable upon the exercise of the Warrants, the kind and amount of shares
of stock and other securities and property receivable in connection with such
Reorganization Event by a holder of the same number of shares of [title of
Preferred Stock purchasable through the exercise of the Warrants] as were
purchasable by the holders of the Warrants immediately prior to such
Reorganization Event. In any such case appropriate provisions shall be made with
respect to the rights and interests of the holders of the Warrants so that the
provisions hereof shall thereafter be applicable with respect to any shares of
stock or other securities and property deliverable upon exercise the Warrants,
and appropriate adjustments shall be made to the Warrant Price payable hereunder
provided the aggregate purchase price shall remain the same. In the case of any
transaction described in clauses (ii) and (iii) above, the Company shall
thereupon be relieved of any further obligation hereunder or under the Warrants,
and the Company as the predecessor corporation may thereupon or at any time
thereafter be dissolved, wound up or liquidated. Such successor or assuming
entity thereupon may cause to be signed, and may issue either in its own name or
in the name of the Company, any or all of the Warrants issuable hereunder which
heretofore shall not have been signed by the Company, and may execute and
deliver securities in its own name, in fulfillment of its obligations to deliver
Warrant Securities upon exercise of the Warrants. All the Warrants so issued
shall in all respects have the same legal rank and benefit under this Agreement
as the Warrants theretofore or thereafter issued in accordance with the terms of
this Agreement as though all of such Warrants had been issued at the date of the
execution hereof. In any case of any such Reorganization Event, such changes in
phraseology and form (but not in substance) may be made in the Warrants
thereafter to be issued as may be appropriate. The Warrant Agent may receive a
written opinion of legal counsel as conclusive evidence that any such
Reorganization Event complies with the provisions of this Section 3.4.


5







(d) The Company may, at its option, at any time until
the Expiration Date, reduce the then current Warrant Price to any amount deemed
appropriate by the Board of Directors of the Company for any period not
exceeding twenty consecutive days (as evidenced in a resolution adopted by such
Board of Directors), but only upon giving the notices required by Section 3.5 at
least ten days prior to taking such action. 

(e) Except as herein otherwise expressly provided, no
adjustment in the Warrant Price shall be made by reason of the issuance of any
securities of the Company or for any other reason whatsoever. 

(f) No fractional Warrant Securities shall be issued
upon the exercise of Warrants. If more than one Warrant shall be exercised at
one time by the same holder, the number of full Warrant Securities which shall
be issuable upon such exercise shall be computed on the basis of the aggregate
number of Warrant Securities purchased pursuant to the Warrants so exercised.
Instead of any fractional Warrant Security which would otherwise be issuable
upon exercise of any Warrant, the Company shall pay a cash adjustment in respect
of such fraction in an amount equal to the same fraction of the last reported
sale price (or bid price if there were no sales) per Warrant Security, in either
case as reported on the principal registered national securities exchange on
which the Warrant Securities are listed or admitted to trading on the business
day that next precedes the day of exercise or, if the Warrant Securities are not
then listed or admitted to trading on any registered national securities
exchange, the average of the closing high bid and low asked prices as reported
on the OTC Bulletin Board Service (the “OTC Bulletin Board”) operated by the Financial Industry Regulatory
Authority, Inc. (“FINRA”) or, if not
available on the OTC Bulletin Board, then the average of the closing high bid
and low asked prices as reported on any other U.S. quotation medium or
inter-dealer quotation system on such date, or if on any such date the Warrant
Securities are not listed or admitted to trading on a registered national
securities exchange, are not included in the OTC Bulletin Board, and are not
quoted on any other U.S. quotation medium or inter-dealer quotation system, an
amount equal to the same fraction of the average of the closing bid and asked
prices as furnished by any FINRA member firm selected from time to time by the
Company for that purpose at the close of business on the business day that next
precedes the day of exercise. 

6







(g) Whenever the Warrant Price then in effect is
adjusted as herein provided, the Company shall mail to each holder of the
Warrants at such holder’s address as it shall appear on the books of the Company
a statement setting forth the adjusted Warrant Price then and thereafter
effective under the provisions hereof, together with the facts, in reasonable
detail, upon which such adjustment is based. 

3.5 Notice To Warrantholders. In case the Company shall (a) effect any
dividend or distribution described in Section 3.4(b), (b) effect any
Reorganization Event, (c) make any distribution on or in respect of the [title
of Preferred Stock purchasable through the exercise of the Warrants] in
connection with the dissolution, liquidation or winding up of the Company, or
(d) reduce the then current Warrant Price pursuant to Section 3.4(d), then the
Company shall mail to each holder of Warrants at such holder’s address as it
shall appear on the books of the Warrant Agent, at least ten days prior to the
applicable date hereinafter specified, a notice stating (x) the record date for
such dividend or distribution, or, if a record is not to be taken, the date as
of which the holders of record of [title of Preferred Stock purchasable through
the exercise of Warrants] that will be entitled to such dividend or distribution
are to be determined, (y) the date on which such Reorganization Event,
dissolution, liquidation or winding up is expected to become effective, and the
date as of which it is expected that holders of [title of Preferred Stock
purchasable through the exercise of the Warrants] of record shall be entitled to
exchange their shares of [title of Preferred Stock purchasable through the
exercise of the Warrants] for securities or other property deliverable upon such
Reorganization Event, dissolution, liquidation or winding up, or (z) the first
date on which the then current Warrant Price shall be reduced pursuant to
Section 3.4(d). No failure to mail such notice nor any defect therein or in the
mailing thereof shall affect any such transaction or any adjustment in the
Warrant Price required by Section 3.4. 

3.6 [If The Warrants Are Subject To Acceleration By The Company,
Insert—Acceleration Of
Warrants By The Company.] 

(a) At any time on or after [●], the Company shall
have the right to accelerate any or all Warrants at any time by causing them to
expire at the close of business on the day next preceding a specified date (the
“Acceleration
Date”), if the Market Price
(as hereinafter defined) of the [title of Preferred Stock purchasable through
the exercise of the Warrants] equals or exceeds [●] percent ([●]%) of the then
effective Warrant Price on any twenty Trading Days (as hereinafter defined)
within a period of thirty consecutive Trading Days ending no more than five
Trading Days prior to the date on which the Company gives notice to the Warrant
Agent of its election to accelerate the Warrants. 

(b) “Market Price” for each
Trading Day shall be, if the [title of Preferred Stock purchasable through the
exercise of the Warrants] is listed or admitted to trading on any registered
national securities exchange, the last reported sale price, regular way (or, if
no such price is reported, the average of the reported closing bid and asked
prices, regular way) of [title of Preferred Stock purchasable through the
exercise of the Warrants], in either case as reported on the principal
registered national securities exchange on which the [title of Preferred Stock
purchasable through the exercise of the Warrants] is listed or admitted to
trading or, if not listed or admitted to trading on any registered national
securities exchange, the average of the closing high bid and low asked prices as
reported on the OTC Bulletin Board operated by FINRA, or if not available on the
OTC Bulletin Board, then the average of the closing high bid and low asked
prices as reported on any other U.S. quotation medium or inter-dealer quotation
system, or if on any such date the shares of [title of Preferred Stock
purchasable through the exercise of the Warrants] are not listed or admitted to
trading on a registered national securities exchange, are not included in the
OTC Bulletin Board, and are not quoted on any other U.S. quotation medium or
inter-dealer quotation system, the average of the closing bid and asked prices
as furnished by any FINRA member firm selected from time to time by the Company
for that purpose. “Trading
Day” shall be each Monday
through Friday, other than any day on which securities are not traded in the
system or on the exchange that is the principal market for the [title of
Preferred Stock purchasable through the exercise of the Warrants], as determined
by the Board of Directors of the Company. 

7







(c) In the event of an acceleration of less than all
of the Warrants, the Warrant Agent shall select the Warrants to be accelerated
by lot, pro rata or in such other manner as it deems, in its discretion, to be
fair and appropriate. 

(d) Notice of an acceleration specifying the
Acceleration Date shall be sent by mail first class, postage prepaid, to each
registered holder of a Warrant Certificate representing a Warrant accelerated at
such holder’s address appearing on the books of the Warrant Agent not more than
sixty days nor less than thirty days before the Acceleration Date. Such notice
of an acceleration also shall be given no more than twenty days, and no less
than ten days, prior to the mailing of notice to registered holders of Warrants
pursuant to this Section 3.6, by publication at least once in a newspaper of
general circulation in the City of New York. 

(e) Any Warrant accelerated may be exercised until [●]
p.m., [City] time, on the business day next preceding the Acceleration Date. The
Warrant Price shall be payable as provided in Section 2.] 

ARTICLE 4 

EXCHANGE AND TRANSFER OF
WARRANT CERTIFICATES 

4.1 Exchange And Transfer Of Warrant
Certificates. Upon surrender at
the corporate trust office of the Warrant Agent, Warrant Certificates evidencing
Warrants may be exchanged for Warrant Certificates in other denominations
evidencing such Warrants or the transfer thereof may be registered in whole or
in part; provided that such other Warrant Certificates evidence Warrants for the
same aggregate number of Warrant Securities as the Warrant Certificates so
surrendered. The Warrant Agent shall keep, at its corporate trust office, books
in which, subject to such reasonable regulations as it may prescribe, it shall
register Warrant Certificates and exchanges and transfers of outstanding Warrant
Certificates, upon surrender of the Warrant Certificates to the Warrant Agent at
its corporate trust office for exchange or registration of transfer, properly
endorsed or accompanied by appropriate instruments of registration of transfer
and written instructions for transfer, all in form satisfactory to the Company
and the Warrant Agent. No service charge shall be made for any exchange or
registration of transfer of Warrant Certificates, but the Company may require
payment of a sum sufficient to cover any stamp or other tax or other
governmental charge that may be imposed in connection with any such exchange or
registration of transfer. Whenever any Warrant Certificates are so surrendered
for exchange or registration of transfer, an authorized officer of the Warrant
Agent shall manually countersign and deliver to the person or persons entitled
thereto a Warrant Certificate or Warrant Certificates duly authorized and
executed by the Company, as so requested. The Warrant Agent shall not be
required to effect any exchange or registration of transfer which will result in
the issuance of a Warrant Certificate evidencing a Warrant for a fraction of a
Warrant Security or a number of Warrants for a whole number of Warrant
Securities and a fraction of a Warrant Security. All Warrant Certificates issued
upon any exchange or registration of transfer of Warrant Certificates shall be
the valid obligations of the Company, evidencing the same obligations and
entitled to the same benefits under this Agreement as the Warrant Certificate
surrendered for such exchange or registration of transfer. 

8







4.2 Treatment Of Holders Of Warrant
Certificates. The Company, the
Warrant Agent and all other persons may treat the registered holder of a Warrant
Certificate as the absolute owner thereof for any purpose and as the person
entitled to exercise the rights represented by the Warrants evidenced thereby,
any notice to the contrary notwithstanding. 

4.3 Cancellation Of Warrant
Certificates. Any Warrant
Certificate surrendered for exchange, registration of transfer or exercise of
the Warrants evidenced thereby shall, if surrendered to the Company, be
delivered to the Warrant Agent and all Warrant Certificates surrendered or so
delivered to the Warrant Agent shall be promptly canceled by the Warrant Agent
and shall not be reissued and, except as expressly permitted by this Agreement,
no Warrant Certificate shall be issued hereunder in exchange therefor or in lieu
thereof. The Warrant Agent shall deliver to the Company from time to time or
otherwise dispose of canceled Warrant Certificates in a manner satisfactory to
the Company. 

ARTICLE 5 

CONCERNING THE WARRANT
AGENT 

5.1 Warrant Agent. The Company hereby appoints [●] as Warrant Agent
of the Company in respect of the Warrants and the Warrant Certificates upon the
terms and subject to the conditions herein set forth, and [●] hereby accepts
such appointment. The Warrant Agent shall have the powers and authority granted
to and conferred upon it in the Warrant Certificates and hereby and such further
powers and authority to act on behalf of the Company as the Company may
hereafter grant to or confer upon it. All of the terms and provisions with
respect to such powers and authority contained in the Warrant Certificates are
subject to and governed by the terms and provisions hereof. 

5.2 Conditions Of Warrant Agent’s
Obligations. The Warrant Agent
accepts its obligations herein set forth upon the terms and conditions hereof,
including the following to all of which the Company agrees and to all of which
the rights hereunder of the holders from time to time of the Warrant
Certificates shall be subject: 

(a) Compensation And Indemnification. The Company agrees promptly to pay the Warrant
Agent the compensation to be agreed upon with the Company for all services
rendered by the Warrant Agent and to reimburse the Warrant Agent for reasonable
out-of-pocket expenses (including reasonable counsel fees) incurred without
negligence, bad faith or willful misconduct by the Warrant Agent in connection
with the services rendered hereunder by the Warrant Agent. The Company also
agrees to indemnify the Warrant Agent for, and to hold it harmless against, any
loss, liability or expense incurred without negligence, bad faith or willful
misconduct on the part of the Warrant Agent, arising out of or in connection
with its acting as Warrant Agent hereunder, including the reasonable costs and
expenses of defending against any claim of such liability. 

(b) Agent For The Company. In acting under this Warrant Agreement and in
connection with the Warrant Certificates, the Warrant Agent is acting solely as
agent of the Company and does not assume any obligations or relationship of
agency or trust for or with any of the holders of Warrant Certificates or
beneficial owners of Warrants. 

(c) Counsel. The Warrant Agent may consult with counsel satisfactory to it, which
may include counsel for the Company, and the written advice of such counsel
shall be full and complete authorization and protection in respect of any action
taken, suffered or omitted by it hereunder in good faith and in accordance with
the advice of such counsel. 

9







(d) Documents. The Warrant Agent shall be protected and shall incur no liability for
or in respect of any action taken or omitted by it in reliance upon any Warrant
Certificate, notice, direction, consent, certificate, affidavit, statement or
other paper or document reasonably believed by it to be genuine and to have been
presented or signed by the proper parties. 

(e) Certain Transactions. The Warrant Agent, and its officers, directors
and employees, may become the owner of, or acquire any interest in, Warrants,
with the same rights that it or they would have if it were not the Warrant Agent
hereunder, and, to the extent permitted by applicable law, it or they may engage
or be interested in any financial or other transaction with the Company and may
act on, or as depositary, trustee or agent for, any committee or body of holders
of Warrant Securities or other obligations of the Company as freely as if it
were not the Warrant Agent hereunder. Nothing in this Warrant Agreement shall be
deemed to prevent the Warrant Agent from acting as trustee under any indenture
to which the Company is a party. 

(f) No Liability For Interest. Unless otherwise agreed with the Company, the
Warrant Agent shall have no liability for interest on any monies at any time
received by it pursuant to any of the provisions of this Agreement or of the
Warrant Certificates. 

(g) No Liability For Invalidity. The Warrant Agent shall have no liability with
respect to any invalidity of this Agreement or any of the Warrant Certificates
(except as to the Warrant Agent’s countersignature thereon). 

(h) No Responsibility For
Representations. The Warrant
Agent shall not be responsible for any of the recitals or representations herein
or in the Warrant Certificates (except as to the Warrant Agent’s
countersignature thereon), all of which are made solely by the Company.


(i) No Implied Obligations. The Warrant Agent shall be obligated to perform
only such duties as are herein and in the Warrant Certificates specifically set
forth and no implied duties or obligations shall be read into this Agreement or
the Warrant Certificates against the Warrant Agent. The Warrant Agent shall not
be under any obligation to take any action hereunder which may tend to involve
it in any expense or liability, the payment of which within a reasonable time is
not, in its reasonable opinion, assured to it. The Warrant Agent shall not be
accountable or under any duty or responsibility for the use by the Company of
any of the Warrant Certificates authenticated by the Warrant Agent and delivered
by it to the Company pursuant to this Agreement or for the application by the
Company of the proceeds of the Warrant Certificates. The Warrant Agent shall
have no duty or responsibility in case of any default by the Company in the
performance of its covenants or agreements contained herein or in the Warrant
Certificates or in the case of the receipt of any written demand from a holder
of a Warrant Certificate with respect to such default, including, without
limiting the generality of the foregoing, any duty or responsibility to initiate
or attempt to initiate any proceedings at law or otherwise or, except as
provided in Section 6.2 hereof, to make any demand upon the Company. 

5.3 Resignation, Removal And Appointment Of
Successors. 

(a) The Company agrees, for the benefit of the holders
from time to time of the Warrant Certificates, that there shall at all times be
a Warrant Agent hereunder until all the Warrants have been exercised or are no
longer exercisable. 

(b) The Warrant Agent may at any time resign as agent
by giving written notice to the Company of such intention on its part,
specifying the date on which its desired resignation shall become effective;
provided that such date shall not be less than three months after the date on
which such notice is given unless the Company otherwise agrees. The Warrant
Agent hereunder may be removed at any time by the filing with it of an
instrument in writing signed by or on behalf of the Company and specifying such
removal and the intended date when it shall become effective. Such resignation
or removal shall take effect upon the appointment by the Company, as hereinafter
provided, of a successor Warrant Agent (which shall be a bank or trust company
authorized under the laws of the jurisdiction of its organization to exercise
corporate trust powers) and the acceptance of such appointment by such successor
Warrant Agent. The obligation of the Company under Section 5.2(a) shall continue
to the extent set forth therein notwithstanding the resignation or removal of
the Warrant Agent. 

10







(c) In case at any time the Warrant Agent shall
resign, or shall be removed, or shall become incapable of acting, or shall be
adjudged a bankrupt or insolvent, or shall commence a voluntary case under the
Federal bankruptcy laws, as now or hereafter constituted, or under any other
applicable Federal or state bankruptcy, insolvency or similar law or shall
consent to the appointment of or taking possession by a receiver, custodian,
liquidator, assignee, trustee, sequestrator (or other similar official) of the
Warrant Agent or its property or affairs, or shall make an assignment for the
benefit of creditors, or shall admit in writing its inability to pay its debts
generally as they become due, or shall take corporate action in furtherance of
any such action, or a decree or order for relief by a court having jurisdiction
in the premises shall have been entered in respect of the Warrant Agent in an
involuntary case under the Federal bankruptcy laws, as now or hereafter
constituted, or any other applicable Federal or state bankruptcy, insolvency or
similar law, or a decree or order by a court having jurisdiction in the premises
shall have been entered for the appointment of a receiver, custodian,
liquidator, assignee, trustee, sequestrator (or similar official) of the Warrant
Agent or of its property or affairs, or any public officer shall take charge or
control of the Warrant Agent or of its property or affairs for the purpose of
rehabilitation, conservation, winding up or liquidation, a successor Warrant
Agent, qualified as aforesaid, shall be appointed by the Company by an
instrument in writing, filed with the successor Warrant Agent. Upon the
appointment as aforesaid of a successor Warrant Agent and acceptance by the
successor Warrant Agent of such appointment, the Warrant Agent shall cease to be
Warrant Agent hereunder. 

(d) Any successor Warrant Agent appointed hereunder
shall execute, acknowledge and deliver to its predecessor and to the Company an
instrument accepting such appointment hereunder, and thereupon such successor
Warrant Agent, without any further act, deed or conveyance, shall become vested
with all the authority, rights, powers, trusts, immunities, duties and
obligations of such predecessor with like effect as if originally named as
Warrant Agent hereunder, and such predecessor, upon payment of its charges and
disbursements then unpaid, shall thereupon become obligated to transfer, deliver
and pay over, and such successor Warrant Agent shall be entitled to receive, all
monies, securities and other property on deposit with or held by such
predecessor, as Warrant Agent hereunder. 

(e) Any corporation into which the Warrant Agent
hereunder may be merged or converted or any corporation with which the Warrant
Agent may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Warrant Agent shall be a party, or any
corporation to which the Warrant Agent shall sell or otherwise transfer all or
substantially all the assets and business of the Warrant Agent, provided that it
shall be qualified as aforesaid, shall be the successor Warrant Agent under this
Agreement without the execution or filing of any paper or any further act on the
part of any of the parties hereto. 

11







ARTICLE 6 

MISCELLANEOUS 

6.1 Amendment. This Agreement may be amended by the parties hereto, without the
consent of the holder of any Warrant Certificate, for the purpose of curing any
ambiguity, or of curing, correcting or supplementing any defective provision
contained herein, or making any other provisions with respect to matters or
questions arising under this Agreement as the Company and the Warrant Agent may
deem necessary or desirable; provided that such action shall not materially
adversely affect the interests of the holders of the Warrant Certificates.


6.2 Notices And Demands To The Company And Warrant
Agent. If the Warrant Agent shall
receive any notice or demand addressed to the Company by the holder of a Warrant
Certificate pursuant to the provisions of the Warrant Certificates, the Warrant
Agent shall promptly forward such notice or demand to the Company. 

6.3 Addresses. Any communication from the Company to the Warrant Agent with respect to
this Agreement shall be addressed to [●], Attention: [●] and any communication
from the Warrant Agent to the Company with respect to this Agreement shall be
addressed to Geron Corporation, 149 Commonwealth Drive, Suite 2070, Menlo Park,
California 94025, Attention: [●] (or such other address as shall be specified in
writing by the Warrant Agent or by the Company). 

6.4 Governing Law. This Agreement and each Warrant Certificate
issued hereunder shall be governed by and construed in accordance with the laws
of the State of New York. 

6.5 Delivery Of Prospectus. The Company shall furnish to the Warrant Agent
sufficient copies of a prospectus meeting the requirements of the Securities Act
of 1933, as amended, relating to the Warrant Securities deliverable upon
exercise of the Warrants (the “Prospectus”), and the
Warrant Agent agrees that upon the exercise of any Warrant, the Warrant Agent
will deliver to the holder of the Warrant Certificate evidencing such Warrant,
prior to or concurrently with the delivery of the Warrant Securities issued upon
such exercise, a Prospectus. The Warrant Agent shall not, by reason of any such
delivery, assume any responsibility for the accuracy or adequacy of such
Prospectus. 

6.6 Obtaining Of Governmental
Approvals. The Company will from
time to time take all action which may be necessary to obtain and keep effective
any and all permits, consents and approvals of governmental agencies and
authorities and securities act filings under United States Federal and state
laws (including without limitation a registration statement in respect of the
Warrants and Warrant Securities under the Securities Act of 1933, as amended),
which may be or become requisite in connection with the issuance, sale,
transfer, and delivery of the Warrant Securities issued upon exercise of the
Warrants, the issuance, sale, transfer and delivery of the Warrants or upon the
expiration of the period during which the Warrants are exercisable. 

6.7 Persons Having Rights Under Warrant
Agreement. Nothing in this
Agreement shall give to any person other than the Company, the Warrant Agent and
the holders of the Warrant Certificates any right, remedy or claim under or by
reason of this Agreement. 

6.8 Headings. The descriptive headings of the several Articles and Sections of this
Agreement are inserted for convenience only and shall not control or affect the
meaning or construction of any of the provisions hereof. 

12







6.9 Counterparts. This Agreement may be executed in any number of
counterparts, each of which as so executed shall be deemed to be an original,
but such counterparts shall together constitute but one and the same instrument.


6.10
Inspection Of
Agreement. A copy of this
Agreement shall be available at all reasonable times at the principal corporate
trust office of the Warrant Agent for inspection by the holder of any Warrant
Certificate. The Warrant Agent may require such holder to submit his Warrant
Certificate for inspection by it. 

13







In Witness
Whereof, the parties hereto have
caused this Agreement to be duly executed, all as of the day and year first
above written. 


	
      GERON
      CORPORATION, as
      Company
 

	By:	 
	Name:	 
	Title:	 
	 	
	 	
	ATTEST:       	 
		 
	 	
	 	
	
      COUNTERSIGNED
 

	
      [●], as Warrant
      Agent 

	By:	 
	Name:	 
	Title:	 
	 	
	 	
	ATTEST:	 
		 




[Signature Page To Preferred Stock Warrant Agreement]

14







EXHIBIT A 

FORM OF WARRANT
CERTIFICATE
[FACE OF
WARRANT CERTIFICATE] 


[Form of Legend if Warrants
are not immediately exercisable.] 



[Prior to [●] Warrants
evidenced by this Warrant Certificate cannot be exercised.] 




EXERCISABLE
ONLY IF COUNTERSIGNED BY THE WARRANT AGENT AS PROVIDED
HEREIN 

VOID AFTER [●] P.M., [City]
time, ON [●]. 

15







GERON
CORPORATION
WARRANT
CERTIFICATE REPRESENTING
WARRANTS TO PURCHASE
[TITLE OF WARRANT SECURITIES] 


No. [●]



[●]
Warrants




This certifies that [●] or registered assigns is the registered owner of
the above indicated number of Warrants, each Warrant entitling such owner to
purchase, at any time [after [●] p.m., [City] time, on [●] and] on or before [●]
p.m., [City] time, on [●] shares of [Title of Warrant Securities] (the
“Warrant
Securities”), of Geron
Corporation (the “Company”) on the
following basis: during the period from [●], through and including [●], the
exercise price per Warrant Security will be $[●], subject to adjustment as
provided in the Warrant Agreement (as hereinafter defined) (the
“Warrant
Price”). The Holder may
exercise the Warrants evidenced hereby by providing certain information set
forth on the back hereof and by paying in full, in lawful money of the United
States of America, [in cash or by certified check or official bank check in New
York Clearing House funds] [by bank wire transfer in immediately available
funds], the Warrant Price for each Warrant Security with respect to which this
Warrant is exercised to the Warrant Agent (as hereinafter defined) and by
surrendering this Warrant Certificate, with the purchase form on the back hereof
duly executed, at the corporate trust office of [name of Warrant Agent], or its
successor as warrant agent (the “Warrant Agent”), which
is, on the date hereof, at the address specified on the reverse hereof, and upon
compliance with and subject to the conditions set forth herein and in the
Warrant Agreement (as hereinafter defined). 

The term “Holder” as used herein shall mean the person in whose name at
the time this Warrant Certificate shall be registered upon the books to be
maintained by the Warrant Agent for that purpose pursuant to Section 4 of the
Warrant Agreement. 

The Warrants evidenced by this Warrant Certificate may be exercised to
purchase a whole number of Warrant Securities in registered form. Upon any
exercise of fewer than all of the Warrants evidenced by this Warrant
Certificate, there shall be issued to the Holder hereof a new Warrant
Certificate evidencing Warrants for the number of Warrant Securities remaining
unexercised. 

This Warrant Certificate is issued under and in accordance with the
Warrant Agreement dated as of [●] (the “Warrant Agreement”), between the Company and the Warrant Agent and
is subject to the terms and provisions contained in the Warrant Agreement, to
all of which terms and provisions the Holder of this Warrant Certificate
consents by acceptance hereof. Copies of the Warrant Agreement are on file at
the above-mentioned office of the Warrant Agent. 

Transfer of this Warrant Certificate may be registered when this Warrant
Certificate is surrendered at the corporate trust office of the Warrant Agent by
the registered owner or such owner’s assigns, in the manner and subject to the
limitations provided in the Warrant Agreement. 

After countersignature by the Warrant Agent and prior to the expiration
of this Warrant Certificate, this Warrant Certificate may be exchanged at the
corporate trust office of the Warrant Agent for Warrant Certificates
representing Warrants for the same aggregate number of Warrant Securities.


This Warrant Certificate shall not entitle the Holder hereof to any of
the rights of a holder of the Warrant Securities, including, without limitation,
the right to receive payments of dividends or distributions, if any, on the
Warrant Securities (except to the extent set forth in the Warrant Agreement) or
to exercise any voting rights. 

16







Reference is hereby made to the further provisions of this Warrant
Certificate set forth on the reverse hereof, which further provisions shall for
all purposes have the same effect as if set forth at this place. 

This Warrant Certificate shall not be valid or obligatory for any purpose
until countersigned by the Warrant Agent. 

17







In Witness
Whereof, the Company has caused
this Warrant to be executed in its name and on its behalf by the facsimile
signatures of its duly authorized officers. 

	Dated: 	 




	 
	GERON CORPORATION, as Company
	 	 
	By:	 
	Name:	 
	Title:	 
	 	 
	ATTEST:       	 
	 	
	 	
 
	COUNTERSIGNED
	 
	[●], as Warrant Agent
	 
	By:	 
	Name:	 
	Title:	 
	 	
	ATTEST:	 
		 




18







[REVERSE OF WARRANT
CERTIFICATE]

(Instructions for
Exercise of Warrant) 

To exercise any Warrants evidenced hereby for Warrant Securities (as
hereinafter defined), the Holder must pay, in lawful money of the United States
of America, [in cash or by certified check or official bank check in New York
Clearing House funds] [by bank wire transfer in immediately available funds],
the Warrant Price in full for Warrants exercised, to [●] [address of Warrant
Agent], Attention: [●], which payment must specify the name of the
Holder and the number of Warrants exercised by such Holder. In addition, the
Holder must complete the information required below and present this Warrant
Certificate in person or by mail (certified or registered mail is recommended)
to the Warrant Agent at the appropriate address set forth above. This Warrant
Certificate, completed and duly executed, must be received by the Warrant Agent
within five business days of the payment. 

(To be executed upon
exercise of Warrants) 

The undersigned hereby irrevocably elects to exercise [●] Warrants,
evidenced by this Warrant Certificate, to purchase [●] shares of the [Title of
Warrant Securities] (the “Warrant Securities”),
of Geron Corporation and represents that he has tendered payment for such
Warrant Securities, in lawful money of the United States of America, [in cash or
by certified check or official bank check in New York Clearing House funds] [by
bank wire transfer in immediately available funds], to the order of Geron
Corporation, c/o [insert name and address of Warrant Agent], in the amount of
$[●] in accordance with the terms hereof. The undersigned requests that said
Warrant Securities be in fully registered form in the authorized denominations,
registered in such names and delivered all as specified in accordance with the
instructions set forth below. 

If the number of Warrants exercised is less than all of the Warrants
evidenced hereby, the undersigned requests that a new Warrant Certificate
evidencing the Warrants for the number of Warrant Securities remaining
unexercised be issued and delivered to the undersigned unless otherwise
specified in the instructions below. 

	Dated: 	 	              	Name:	 
				Please Print



	Address:
	 
 
	(Insert Social Security or Other Identifying Number of
      Holder)



	Signature Guaranteed: 	 
		Signature



(Signature must conform in
all respects to name of holder as specified on the face of this Warrant
Certificate and must bear a signature guarantee by a FINRA member firm).


This Warrant may be
exercised at the following addresses:

By hand at:

By mail at: 

19







[Instructions as to form
and delivery of Warrant Securities and, if applicable, Warrant Certificates
evidencing Warrants for the number of Warrant Securities remaining
unexercised—complete as appropriate.] 

20







ASSIGNMENT 

[Form of assignment to be
executed if Warrant Holder desires to transfer Warrant]

       For Value Received, [●] hereby sells, assigns and transfers unto: 

	 		 
	(Please print name and address including zip code)	       	Please print Social Security or other identifying
  number



the right represented by
the within Warrant to purchase [●] shares of [Title of Warrant Securities] of
Geron Corporation to which the within Warrant relates and appoints [●] attorney
to transfer such right on the books of the Warrant Agent with full power of
substitution in the premises. 

	Dated:  	 	       	 
		 	Signature



(Signature must conform in all respects to name of holder as specified on
the face of the Warrant) 

	Signature Guaranteed
	
 



21