EXHIBIT 4.5


GERON CORPORATION 

AND 

_____________, AS WARRANT
AGENT


FORM OF
COMMON STOCK 
WARRANT AGREEMENT 

DATED AS
OF __________ 







GERON CORPORATION


FORM OF COMMON STOCK
WARRANT AGREEMENT 

This Common 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 Common Stock of the Company, par value $0.001 per share
(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.

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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 Common Stock 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 Common Stock 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 Common Stock (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) Common Stock
or any shares of stock or other securities which are at any time directly or
indirectly convertible into or exchangeable for Common Stock, 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 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) Common Stock
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 Common Stock 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 Common Stock 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 Common Stock 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 Common Stock other than the issuance of additional
shares of Common Stock) 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 Warrant Securities 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.

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(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 shares of Common Stock, or securities
convertible into or exchangeable for shares of Common Stock, or securities
carrying the right to purchase any of the foregoing 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. 

(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 Common Stock 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 Common Stock
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 Common Stock of record shall be entitled to exchange their shares of
Common Stock 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.

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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 Common Stock 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 Common Stock 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 Common Stock, in either case as reported on the
principal registered national securities exchange on which the Common Stock 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 Common Stock
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 Common Stock, as determined by the Board of
Directors of the Company. 

(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.

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(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. 

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. 

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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. 

(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.


9







(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. 

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).


11







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. 

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. 

12







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 Geron
Corporation Form of Common Stock Warrant Agreement]


13







EXHIBIT A 

FORM OF WARRANT
CERTIFICATE
[FACE OF WARRANT CERTIFICATE] 

	[Form of
      Legend if Warrants are not immediately	[Prior to
      [●] Warrants evidenced by this Warrant
	exercisable.]	Certificate
      cannot be exercised.]



EXERCISABLE ONLY IF
COUNTERSIGNED BY THE WARRANT AGENT AS PROVIDED
HEREIN 

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

14 







GERON CORPORATION

WARRANT CERTIFICATE
REPRESENTING
WARRANTS TO PURCHASE 
COMMON STOCK, PAR VALUE $0.001 PER SHARE



	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 Common Stock, par value $0.001 per share (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.


15







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. 

16







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:	
	 	 	 



17 







[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 Common Stock, par value $0.001 per
share (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: 

18







By mail at: 

[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.] 

19







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:   		     	Name:    	
		 			Signature



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


	Signature
      Guaranteed
	 



20