EXHIBIT 4.7







GERON CORPORATION 

AND 

_____________, AS WARRANT
AGENT


FORM OF
DEBT SECURITIES
WARRANT AGREEMENT 

DATED AS
OF __________ 












GERON CORPORATION


FORM OF DEBT SECURITIES
WARRANT AGREEMENT 

THIS DEBT
SECURITIES 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 has entered into an indenture dated as of [[●] (the “Senior
Indenture”), with
[●], as trustee (such trustee, and any successors to such trustee, herein
called the “Senior
Trustee”), providing for the
issuance from time to time of its unsubordinated debt securities, to be issued
in one or more series as provided in the Senior Indenture (the
“Debt
Securities”);] [[●] (the “Subordinated Indenture”), with [●], as trustee (such trustee, and any successors to
such trustee, herein called the “Subordinated Trustee”), providing for the issuance from time to time of its subordinated debt
securities, to be issued in one or more series as provided in the Subordinated
Indenture (the “Debt
Securities”);] 

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 Debt Securities
purchasable through exercise of Warrants] (the “Warrant Debt 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 Debt 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







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. 

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 Debt 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 principal amount of Warrant Debt Securities specified
in the applicable Warrant Certificate at an exercise price of [●]% of the principal amount thereof [plus accrued
amortization, if any, of the original issue discount of the Warrant Debt
Securities] [plus accrued interest, if any, from the most recent date from which
interest shall have been paid on the Warrant Debt Securities or, if no interest
shall have been paid on the Warrant Debt Securities, from the date of their
initial issuance.] [The original issue discount ($[●] for each $1,000 principal
amount of Warrant Debt Securities) will be amortized at a [●]% annual rate, computed on a[n] [semi-] annual
basis [using a 360-day year consisting of twelve 30-day months].] Such purchase price for the Warrant Debt
Securities is referred to in this Agreement as the “Warrant Price.” 

2







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. 

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 Debt 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 Debt 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
Debt 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 Debt 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 Debt Securities on such date,
but shall be effective to constitute such person as the holder of record of such
Warrant Debt Securities for all purposes at the opening of business on the next
succeeding day on which the transfer books for the Warrant Debt Securities
purchasable upon the exercise of such Warrants shall be opened, and the
certificates for the Warrant Debt 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 Debt
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 Debt 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 Debt 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 Debt Securities after such exercise, and (iv) such other information as
the Company or the [Senior] [Subordinated] Trustee shall reasonably require.


(c) As soon as
practicable after the exercise of any Warrant, the Company shall issue, pursuant
to the Indenture, in authorized denominations, to or upon the order of the
holder of the Warrant Certificate evidencing such Warrant, the Warrant Debt
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 Debt Securities
remaining unexercised. 

3







(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 Debt Securities, and in the event that any such transfer is involved,
the Company shall not be required to issue or deliver any Warrant Debt
Securities 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. 

(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 Debt 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 Holders of Warrant Debt Securities 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 Debt Securities, including, without
limitation, the right to receive the payment of principal of (or premium, if
any) or interest, if any, on the Warrant Debt Securities or to enforce any of
the covenants in the Indenture. 

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 principal
amount of Warrant Debt 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 [Senior]
[Subordinated] Trustee, the holder of any Warrant Debt 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 Certificates and in this Agreement.


4 







3.4 Merger,
Sale, Conveyance or Lease. In
case of (a) any 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) or (b) 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’s successor shall be delivered to the holders of the Warrants, so that
such successor shall succeed to and be substituted for the Company, and assume
all the Company’s obligations under, this Agreement and the Warrants. 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 Debt 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. 

3.5 Notice to
Warrantholders. In case the
Company shall (a) effect any Reorganization Event or (b) make any distribution
on or in respect of the [title of Warrant Debt Securities] in connection with
the dissolution, liquidation or winding up of the Company, 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 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 Warrant Debt Securities] of record shall be entitled to exchange their shares
of [title of Warrant Debt Securities] for securities or other property
deliverable upon such Reorganization Event, dissolution, liquidation or winding
up. No failure to mail such notice nor any defect therein or in the mailing
thereof shall affect any such transaction. 

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 principal amount of
Warrant Debt 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 Debt Security or a
number of Warrants for a whole number of Warrant Debt Securities and a fraction
of a Warrant Debt 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. 

5







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. 

6







(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 Debt 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 [Senior] [Subordinated] Trustee under the [Senior]
[Subordinated] Indenture. 

(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. 

7







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. 

(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.


8







(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). 

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
Debt 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 Debt 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 Debt 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 Debt 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. 

9







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 DEBT
SECURITIES WARRANT AGREEMENT] 

10







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 [●]. 

11







GERON CORPORATION

WARRANT CERTIFICATE
REPRESENTING
WARRANTS TO PURCHASE
[TITLE OF WARRANT DEBT
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, $[●] principal amount of [Title of Warrant Debt
Securities] (the “Warrant Debt
Securities”) of Geron
Corporation (the “Company”) issued or to
be issued under the Indenture (as hereinafter defined), on the following basis:
during the period from [●], through
and including [●], each Warrant shall
entitle the Holder thereof, subject to the provisions of this Agreement, to
purchase the principal amount of Warrant Debt Securities stated in the Warrant
Certificate at the warrant price (the “Warrant Price”) of
[●]% of the principal amount thereof
[plus accrued amortization, if any, of the original issue discount of the
Warrant Debt Securities] [plus accrued interest, if any, from the most recent
date from which interest shall have been paid on the Warrant Debt Securities or,
if no interest shall have been paid on the Warrant Debt Securities, from the
date of their original issuance]. [The original issue discount ($[●] for each
$1,000 principal amount of Warrant Debt Securities) will be amortized at a
[●]% annual rate, computed on a[n]
[semi-]annual basis [using a 360-day year consisting of twelve 30-day months].
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 Debt 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 Warrant Debt Securities in
the principal amount of $1,000 or any integral multiple thereof 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 aggregate principal amount of Warrant
Debt 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. 

12







The Warrant Debt Securities
to be issued and delivered upon the exercise of Warrants evidenced by this
Warrant Certificate will be issued under and in accordance with an Indenture,
[dated as of [●] (the “Senior
Indenture”), between the
Company and [●], as trustee (such
trustee, and any successors to such trustee, the “Senior Trustee”)] [dated as of [●], (the “Subordinated Indenture”), between the Company and [●], as trustee (such trustee, and any successors to such trustee, the
“Subordinated
Trustee”)] and will be
subject to the terms and provisions contained in the Warrant Debt Securities and
in the Indenture. Copies of the [Senior] [Subordinated] Indenture, including the
form of the Warrant Debt Securities, are on file at the corporate trust office
of the [Senior][Subordinated] Trustee. 

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 principal amount of Warrant Debt Securities. 

This Warrant Certificate
shall not entitle the Holder hereof to any of the rights of a holder of the
Warrant Debt Securities, including, without limitation, the right to receive
payments of principal of (and premium, if any) or interest, if any, on the
Warrant Debt Securities or to enforce any of the covenants of the Indenture.


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. 

13







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:	
	 	
	 	




14







[REVERSE OF WARRANT
CERTIFICATE] 

(Instructions for
Exercise of Warrant) 

To exercise any Warrants
evidenced hereby for Warrant Debt 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, represented by this Warrant
Certificate, to purchase $[●] principal amount of the [Title of Warrant Debt
Securities] (the “Warrant Debt
Securities”) of Geron
Corporation and represents that he has tendered payment for such Warrant Debt
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
principal amount of Warrant Debt 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 the Warrants evidenced hereby, the undersigned
requests that a new Warrant Certificate evidencing the Warrants for the
aggregate principal amount of Warrant Debt 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: 



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

15







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 $[●] aggregate principal amount of shares [Title
of Warrant Debt 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
      

	 


16