exhibit4-3.htm


    EXHIBIT 4.3 

     

    COMMON STOCK PURCHASE AGREEMENT


     

    THIS COMMON STOCK
PURCHASE AGREEMENT (“Agreement”) is made and entered into as of April 1, 2010
(the “Effective Date”), by and between Geron Corporation, a Delaware corporation
having its principal place of business at 230 Constitution Drive, Menlo Park,
California 94025 (“Geron”), and Prime Synthesis, Inc., a Pennsylvania
corporation having its principal place of business at 2 New Road, Suite 126,
Aston PA 19014 (“Company”). 

     

    
      	      	A.	      	Geron
      and Company are the parties to that certain Master Supply Agreement dated
      as of May 13, 2005 (the “Master
      Agreement”),
      and related Addendum Agreements under which Geron and Company have agreed
      that Company will perform certain services on behalf of Geron on the terms
      set forth therein.
	
            	 
	
            	B.	
            	Pursuant to the Master Agreement, Geron may pay for the price of
      such services by delivery of shares of Geron’s Common Stock (the
      “Shares”).
	
            	 
	
            	C.	
            	Geron
      has elected to make payment for certain such services through the delivery
      of Shares, pursuant to the terms and conditions of the Master Agreement
      and this Agreement.


    

     

    THE PARTIES AGREE AS
FOLLOWS: 

     

    
      	1.	
            	ISSUANCE OF SHARES;
      ADJUSTMENTS.
	 
	 	      	1.1	
            	As payment of the budget set forth in Addendum Agreement No. 6,
      Geron will issue and deliver to Company certificates for 24,536 Shares.
      Upon issuance and delivery of the certificate(s) for the Shares, all
      Shares shall be duly authorized and validly issued and represent fully
      paid shares of Geron’s Common Stock.
	 
	2.	
            	CLOSING; DELIVERY.
	 
	 	
            	2.1	
            	The consummation of the transaction contemplated by this Agreement
      (the “Closing”) shall be held at such time and place
      as is mutually agreed upon between the parties, but in any event Geron
      shall make commercially reasonable efforts to accomplish the Closing no
      later than five (5) business days after the Effective Date hereof (the
      “Closing Date”). At the Closing, Geron shall deliver
      to Company one or more certificates representing all of the Shares, which
      Shares shall be issued in the name of Company or its designee and in such
      denominations as Company shall specify.
	 
	 	
            	2.2	
            	Geron’s obligations to issue and deliver the stock certificate(s)
      representing the Shares to Company at the Closing shall be subject to the
      following conditions, which may be waived by Geron:
	 
	 	
            	 	      	2.2.1	      	the
      covenants and obligations that Company is required to perform or to comply
      with pursuant to this Agreement, at or prior to the Closing, must have
      been duly performed and complied with in all material respects;
    and
	 
	 	
            	 	
            	2.2.2	 	the
      representations and warranties made by Company herein shall be true and
      correct in all material respects as of the Closing
  Date.


    


    

    
    


    
      	 	
            	2.3	
            	Company’s obligation to accept delivery of the stock certificate(s)
      representing the Shares at the Closing shall be subject to the following
      conditions, any one or more of which may be waived by
Company:
	 
	 	
            	 	
            	2.3.1	      	the
      covenants and obligations that Geron is required to perform or to comply
      with pursuant to this Agreement, at or prior to the Closing, must have
      been duly performed and complied with in all material
  respects;
	 
	 	
            	 	
            	2.3.2	
            	Geron
      shall have available under its Certificate of Incorporation sufficient
      authorized shares of Common Stock to issue the Shares to Company;
      and
	 
	 	
            	 	
            	2.3.3	
            	the
      representations and warranties made by Geron herein shall be true and
      correct in all material respects as of the Closing Date.
	 
	3.	
            	RESTRICTIONS ON RESALE OF
      SHARES.
	 
	 	
            	3.1	
            	Legends. Company understands and acknowledges
      that the Shares are not registered under the Securities Act of 1933 (the
      “Act”), and that under the Act and other
      applicable laws Company may be required to hold such Shares for an
      indefinite period of time. Each stock certificate representing Shares
      shall bear the following legend:
	 
	 	      	 	      	“THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER
      THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”). ANY TRANSFER OF SUCH
      SECURITIES SHALL BE INVALID UNLESS A REGISTRATION STATEMENT UNDER THE ACT
      IS IN EFFECT AS TO SUCH TRANSFER OR, IN THE OPINION OF COUNSEL REASONABLY
      ACCEPTABLE TO GERON, SUCH REGISTRATION IS UNNECESSARY FOR SUCH TRANSFER TO
      COMPLY WITH THE ACT. THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE
      TERMS OF THE COMMON STOCK PURCHASE AGREEMENT BY AND BETWEEN GERON AND
      COMPANY DATED AS OF APRIL 1, 2010. A COPY OF THE AGREEMENT CAN BE OBTAINED
      FROM THE SECRETARY OF GERON.”
	 
	 	
            	3.2	
            	Limits on Sales. Company agrees that if it decides to
      resell some or all of the Shares, it will do so only through orderly sales
      executed through a top tier brokerage house, and in an appropriate manner
      based upon whether the shares are registered or unregistered, i.e., on the
      Nasdaq National Market or in a Rule 144A or Rule 144 compliant
      transaction. Company further agrees that it will not engage in short
      selling with respect to Geron’s Common Stock.
	 
	 	
            	3.3	
            	Removal of Legends. Any legend endorsed on a certificate
      evidencing the Shares shall be removed, and Geron shall issue a
      certificate without such legend to the holder of such Shares, if such
      Shares are being sold pursuant to an effective registration statement
      under the Act or pursuant to Rule 144 promulgated thereunder, and the
      purchaser of Shares so sold may immediately resell such Shares without
      restriction and without registration; provided, however, that in the case
      of a sale pursuant to Rule 144, such holder of Shares shall provide such
      information as is reasonably requested by Geron to ensure that such Shares
      may be sold in reliance on Rule 144.
	 
	 	
            	3.4	
            	Further Limitations. Geron shall not be required (i) to
      transfer on its books any Shares that have been sold or otherwise
      transferred in violation of any of the provisions of this Agreement or
      applicable securities laws; or (ii) to treat as owner of such Shares or to
      accord the right to vote or pay dividends to any purchaser or other
      transferee to whom such Shares shall have been so transferred in violation
      of any of the provisions of this Agreement or applicable securities
      laws.


    


    

    
    


    
      	4.	
            	REGISTRATION RIGHTS
	 
	 	      	4.1	      	Geron agrees to
      make commercially reasonable efforts to file with the Securities and
      Exchange Commission (the “Commission”), within ten (10) business days after
      the Closing Date, a registration statement under the Act (the
      “Registration
      Statement”),
      on Form S-3 or other appropriate form, so as to permit a non-underwritten
      public offering and resale of the Shares under the Act by Company. Geron
      will exercise commercially reasonable efforts to cause the form of the
      Registration Statement to comply with all applicable requirements of the
      Act and the regulations of the Commission thereunder. Geron agrees to
      diligently pursue making the Registration Statement effective. Geron will
      make commercially reasonable efforts to notify Company of the
      effectiveness of the Registration Statement within one (1) business day of
      receiving notice from the Commission declaring the Registration Statement
      effective.
	 
	 	
            	4.2	
            	Geron will make
      commercially reasonable efforts to maintain the Registration Statement and
      any post-effective amendment thereto filed under this Section 4 effective
      under the Act until the earliest of (i) the date that none of the Shares
      covered by such Registration Statement are issued and outstanding, (ii)
      the date that all of the Shares have been sold pursuant to such
      Registration Statement, (iii) the date that all Shares have been otherwise
      transferred to persons who may trade such Shares without restriction under
      the Act, and Geron has delivered a new certificate or other evidence of
      ownership for such securities not bearing a restrictive legend, or (iv)
      the date all Shares may be sold at any time, without volume or manner of
      sale limitations, pursuant to Rule 144 or any similar provision then in
      effect under the Act, in the opinion of counsel to Geron, which counsel
      shall be reasonably acceptable to Company.
	 
	 	
            	4.3	
            	Geron, at its
      expense, shall furnish to Company with respect to the Shares registered
      under the Registration Statement such reasonable number of copies of the
      Registration Statement, prospectuses and preliminary prospectuses in
      conformity with the requirements of the Act and such other documents as
      Company may reasonably request, in order to facilitate the public sale or
      other disposition of all or any of the Shares by Company, provided,
      however, that the obligation of Geron to deliver copies of prospectuses or
      preliminary prospectuses to Company shall be subject to the receipt by
      Geron of reasonable assurances from Company that Company will comply with
      the applicable provisions of the Act and of such other securities or blue
      sky laws as may be applicable in connection with any use of such
      prospectuses or preliminary prospectuses.
	 
	 	
            	4.4	
            	All fees,
      disbursements and out-of-pocket expenses and costs incurred by Geron in
      connection with the preparation and filing of the Registration Statement
      under Section 4.1 and in complying with applicable securities and Blue Sky
      laws (including, without limitation, all attorneys' fees of Geron) shall
      be borne by Geron. Company shall bear the cost of fees and expenses of
      Company’s counsel.
	 
	 	
            	4.5	
            	Geron will advise
      Company promptly after it shall receive notice or obtain knowledge of the
      issuance of any stop order by the Commission delaying or suspending the
      effectiveness of the Registration Statement or of the initiation of any
      proceeding for that purpose, and Geron will use its commercially
      reasonable efforts to prevent the issuance of any stop order or to obtain
      its withdrawal as promptly as possible if such stop order should be
      issued. If any event or circumstance occurs that causes the Registration
      Statement or any prospectus or supplement therein to not comply with the
      Act or the rules and regulations issued thereunder, Geron shall promptly
      notify Company and shall make commercially reasonable efforts to promptly
      amend or supplement the Registration Statement and/or prospectus so as to
      bring it into compliance with the Act and the rules and regulations
      thereunder. Upon such notification by Geron of the foregoing, Company will
      promptly suspend its offer and sale of Shares until Geron has notified
      Company that it has prepared and filed with the Commission a supplement or
      amendment to the Registration Statement and has been notified of the
      effectiveness of the Registration Statement, as supplemented or
      amended.


    


    

    
    


    
      	 	
            	4.6	      	With a
      view to making available to Company the benefits of Rule 144 (or its
      successor rule) and any other rule or regulation of the Commission that
      may at the time permit Company to sell the Shares to the public without
      registration, Geron covenants and agrees to: (i) make and keep public
      information available, as those terms are understood and defined in Rule
      144, until the earliest of (A) such date as all of the Shares may be
      resold pursuant to Rule 144 or any other rule of similar effect or (B)
      such date as all of the Shares shall have been resold; and (ii) file with
      the Commission in a timely manner all reports and other documents required
      of Geron under the Act and under the Securities Exchange Act of 1934 (the
      “Exchange Act”), as amended.
	 
	 	      	4.7	
            	Company will cooperate with Geron in all respects in connection
      with this Agreement, including timely supplying all information reasonably
      requested by Geron (which shall include all information regarding Company
      and proposed manner of sale of the Shares required to be disclosed in any
      Registration Statement) and executing and returning all documents
      reasonably requested in connection with the registration and sale of the
      Shares. Nothing in this Agreement shall obligate Company to consent to be
      named as an underwriter in any Registration Statement.
	 
	 	
            	4.8	
            	Geron
      shall make commercially reasonable efforts to prepare and file with the
      SEC such amendments and supplements to the Registration Statement as may
      be necessary to comply with the provisions of the Act with respect to the
      disposition of all Shares covered by the Registration Statement; provided,
      however, that before filing a registration statement or any amendments or
      supplements thereto, or comparable statements under securities or blue sky
      laws of any jurisdiction, Geron will furnish to one counsel to be
      designated by Company, copies of all such documents proposed to be
      filed.
	 
	5.	
            	INDEMNIFICATION.
	 
	 	
            	5.1	
            	Geron
      agrees to indemnify and hold harmless Company (and each person, if any,
      who controls Company within the meaning of Section 15 of the Act, and each
      officer and director of Company) against any and all losses, claims,
      damages or liabilities (or actions or proceedings in respect thereof),
      joint or several, directly or indirectly based upon or arising out of (i)
      any untrue statement or alleged untrue statement of any material fact
      contained in the Registration Statement, any preliminary prospectus, final
      prospectus or summary prospectus contained therein or used in connection
      with the offering of the Shares, or any amendment or supplement thereto,
      or (ii) any omission or alleged omission to state a material fact required
      to be stated therein or necessary to make the statements therein not
      misleading; and Geron will reimburse each such indemnified party for any
      legal or any other expenses reasonably incurred by them in connection with
      investigating, preparing, pursuing or defending any such loss, claim,
      damage, liability, action or proceeding, except insofar as any such loss,
      claim, damage, liability, action, proceeding or expense arises out of or
      is based upon (A) an untrue statement or alleged untrue statement or
      omission or alleged omission made in the Registration Statement, any such
      preliminary prospectus, final prospectus, summary prospectus, amendment or
      supplement in reliance upon and in conformity with written information
      furnished to Geron by Company or such other person expressly for use in
      the preparation thereof, (B) the failure of Company to comply with its
      covenants and agreements contained in Sections 7.1 or 7.5.3 hereof or (C)
      any misstatement or omission in any prospectus that is corrected in any
      subsequent prospectus that was delivered to Company prior to the pertinent
      sale or sales by Company. Such indemnity shall remain in full force and
      effect, regardless of any investigation made by such indemnified party and
      shall survive the transfer of the Shares by Company.
	 
	 	
            	5.2	
            	Company agrees to indemnify and hold harmless Geron (and each
      person, if any, who controls Geron within the meaning of Section 15 of the
      Act, and each officer and director of Geron) from and against losses,
      claims, damages or liabilities (or actions or proceedings in respect
      thereof), joint or several, directly or indirectly based upon or arising
      out of, (i) any failure of Company to comply with the covenants and
      agreements contained in Sections 7.1 and 7.5.3 hereof or (ii) any untrue
      statement of a material fact contained in the Registration Statement or
      any omission of a material fact required to be stated in the Registration
      Statement or necessary in order to make the statements in the Registration
      Statement not misleading if such untrue statement or omission was made in
      reliance upon and in conformity with written information furnished to
      Geron by or on behalf of Company specifically for use in preparation of
      the Registration Statement; provided, however, that Company shall not be
      liable in any such case for (A) any untrue statement or omission in the
      Registration Statement, prospectus, or other such document which statement
      is corrected by Company and delivered to Geron prior to the sale from
      which such loss occurred, (B) any untrue statement or omission in any
      prospectus which is corrected by Company in any subsequent prospectus, or
      supplement or amendment thereto, and delivered to Geron prior to the sale
      or sales from which a loss or liability arose, or (C) any failure by Geron
      to fulfill any of its obligations under Section 5.1
  hereof.


    


    

    
    


    
      	 	      	5.3	      	Promptly after receipt by any indemnified person of a notice of a
      claim or the beginning of any action in respect of which indemnity is to
      be sought against an indemnifying person pursuant to this Section 5, such
      indemnified person shall notify the indemnifying person in writing of such
      claim or of the commencement of such action, but the omission to so notify
      the indemnifying party will not relieve it from any liability which it may
      have to any indemnified party under this Section 5 (except to the extent
      that such omission materially and adversely affects the indemnifying
      party’s ability to defend such action) or from any liability otherwise
      than under this Section 5. Subject to the provisions hereinafter stated,
      in case any such action shall be brought against an indemnified person,
      the indemnifying person shall be entitled to participate therein, and, to
      the extent that it shall elect by written notice delivered to the
      indemnified party promptly after receiving the aforesaid notice from such
      indemnified party, shall be entitled to assume the defense thereof, with
      counsel reasonably satisfactory to such indemnified person. After notice
      from the indemnifying person to such indemnified person of its election to
      assume the defense thereof, such indemnifying person shall not be liable
      to such indemnified person for any legal expense subsequently incurred by
      such indemnified person in connection with the defense thereof, provided,
      however, that if there exists or shall exist a conflict of interest that
      would make inappropriate, in the reasonable opinion of counsel to the
      indemnified person, for the same counsel to represent both the indemnified
      person and such indemnifying person or any affiliate or associate thereof,
      the indemnified person shall be entitled to retain its own counsel at the
      expense of such indemnifying person; provided, however, that no
      indemnifying person shall be responsible for the fees and expenses of more
      than one separate counsel (together with appropriate local counsel) for
      all indemnified parties. In no event shall any indemnifying person be
      liable in respect to any amounts paid in settlement of any action unless
      the indemnifying person shall have approved the terms of such settlement.
      No indemnifying person shall, without the prior written consent of the
      indemnified person, effect any settlement of any pending or threatened
      proceeding in respect of which any indemnified person is or could have
      been a party and indemnification could have been sought hereunder by such
      indemnified person, unless such settlement includes an unconditional
      release of such indemnified person from all liability on claims that are
      the subject matter of such proceeding.
	 
	 	
            	5.4	
            	The
      provisions of this Section 5 shall survive the termination of this
      Agreement.
	 
	6.	
            	REPRESENTATIONS AND COVENANTS OF
      GERON.
	 
	 	
            	Geron hereby represents, warrants and covenants to Company as
      follows:
	 
	 	
            	6.1	
            	Organization, Good Standing and
      Qualification. Geron
      is a corporation duly organized, validly existing and in good standing
      under the laws of the State of Delaware and has all requisite corporate
      power and authority to carry on its business as now conducted and as
      presently proposed to be conducted. Geron is duly qualified to transact
      business and is in good standing as a foreign corporation in each
      jurisdiction in which the failure to so qualify would have a material
      adverse effect on its business or
properties.


    


    

    
    


    
      	 	      	6.2	      	Authorization. All corporate action on the part of
      Geron, its officers, directors and stockholders necessary for the
      authorization, execution and delivery of this Agreement, the performance
      of all obligations of Geron hereunder and the authorization, issuance and
      delivery of the Shares has been taken or will be taken prior to the
      Closing, and this Agreement, when executed and delivered, will constitute
      the valid and legally binding obligations of Geron, enforceable against
      Geron in accordance with its terms, except as limited by applicable
      bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance
      and other laws of general application affecting enforcement of creditors’
      rights generally, as limited by laws relating to the availability of
      specific performance, injunctive relief or other equitable remedies. The
      execution and performance by Geron of its obligations under this Agreement
      does not conflict with (a) the charter or bylaws of Geron or (b) any law,
      rule or regulation applicable to Geron which would have a material adverse
      effect on Geron’s performance of its obligations hereunder, and to the
      best of Geron’s knowledge as of the Effective Date, does not cause a
      material breach under or default of any material contract or agreement to
      which Geron is a party or by which any of its material properties or
      assets are bound.
	 
	 	
            	6.3	
            	Valid Issuance of Common Stock.
      The Shares, when
      issued, sold and delivered in accordance with the terms hereof for the
      consideration expressed herein, will be duly and validly authorized and
      issued, fully paid and nonassessable and free of restrictions on transfer
      other than restrictions on transfer under this Agreement and applicable
      state and federal securities laws.
	 
	 	
            	6.4	
            	Legal Proceedings and Orders.
      There is no action,
      suit, proceeding or investigation pending or threatened against Geron that
      questions the validity of this Agreement or the right of Geron to enter
      into this Agreement or to consummate the transactions contemplated hereby,
      nor is Geron aware of any basis for any of the forgoing. Geron is neither
      a party to nor subject to the provisions of any order, writ, injunction,
      judgment or decree of any court or government agency or instrumentality
      that would affect the ability of Geron to enter into this Agreement or to
      consummate the transactions contemplated hereby.
	 
	 	
            	6.5	
            	Securities Compliance.
      To the best of its
      knowledge as of the Effective Date of this Agreement, Geron is in material
      compliance with all applicable requirements of the Act, and the rules of
      the Nasdaq Global Market, and has made all filings required to be made by
      it with the Commission.
	 
	7.	
            	REPRESENTATIONS AND ACKNOWLEDGMENTS OF
      COMPANY.
	 
	 	
            	Company hereby represents, warrants, acknowledges and agrees
      that:
	 
	 	
            	7.1	
            	Investment. Company is acquiring the Shares for
      Company’s own account, and not directly or indirectly for the account of
      any other person. Company is acquiring the Shares for investment and not
      with a view to distribution or resale thereof, except in compliance with
      the Act and any applicable state law regulating securities.
	 
	 	
            	7.2	
            	Access to Information.
      Company has
      consulted with its own attorney, accountant, or investment advisor as
      Company has deemed advisable with respect to the investment and has
      determined its suitability for Company. Company has had the opportunity to
      ask questions of, and to receive answers from, appropriate executive
      officers of Geron with respect to the terms and conditions of the
      transactions contemplated hereby and with respect to the business,
      affairs, financial condition and results of operations of Geron. Company
      has had access to such financial and other information as is necessary in
      order for Company to make a fully informed decision as to investment in
      Geron, and has had the opportunity to obtain any additional information
      necessary to verify any of such information to which Company has had
      access. Company acknowledges that neither Geron nor any of its officers,
      directors, employees, agents, representatives, or advisors has made any
      representation or warranty other than those specifically expressed
      herein.


    


    

    
    


    
      	
            	
            	7.3	      	Business and Financial Expertise.
      Company further
      represents and warrants that it has such business or financial expertise
      as to be able to evaluate its investment in Geron and purchase of the
      Shares.
	
            	 
	
            	
            	7.4	
            	Speculative Investment.
      Company acknowledges
      that the investment in Geron represented by the Shares is highly
      speculative in nature and is subject to a high degree of risk of loss in
      whole or in part; the amount of such investment is within Company’s risk
      capital means and is not so great in relation to Company’s total financial
      resources as would jeopardize the personal financial needs of Company in
      the event such investment were lost in whole or in part.
	
            	 
	
            	
            	7.5	
            	Unregistered Securities. Company acknowledges
      that:
	
            	 
	
            	
            	 	
            	7.5.1	      	Company must bear the economic risk of investment for an indefinite
      period of time because the Shares have not been registered under the Act
      and therefore cannot and will not be sold unless they are subsequently
      registered under the Act or an exemption from such registration is
      available. Geron has made no agreements, covenants or undertakings
      whatsoever to register any of the Shares under the Act, except as provided
      in Section 4 above. Geron has made no representations, warranties or
      covenants whatsoever as to whether any exemption from the Act, including,
      without limitation, any exemption for limited sales in routine brokers’
      transactions pursuant to Rule 144 under the Act, will become available and
      any such exemption pursuant to Rule 144, if available at all, will not be
      available unless: (i) a public trading market then exists in Geron’s
      common stock, (ii) Geron has complied with the information requirements of
      Rule 144, and (iii) all other terms and conditions of Rule 144 have been
      satisfied.
	
            	 
	
            	
            	 	
            	7.5.2	
            	Transfer of the Shares has not been registered or qualified under
      any applicable state law regulating securities and, therefore, the Shares
      cannot and will not be sold unless they are subsequently registered or
      qualified under any such act or an exemption therefrom is available. Geron
      has made no agreements, covenants or undertakings whatsoever to register
      or qualify any of the Shares under any such act except as provided in
      Section 4 above. Geron has made no representations, warranties or
      covenants whatsoever as to whether any exemption from any such act will
      become available.
	
            	 
	
            	
            	 	
            	7.5.3	
            	Company hereby certifies that it is an “Accredited
      Investor” as
      that term is defined in Rule 501 under the Act.
	
            	 
	
            	     	7.6	
            	Authorization. Company has full right, power, authority
      and capacity to enter into this Agreement and to consummate the
      transactions contemplated hereby and thereby and has taken all necessary
      action to authorize the execution, delivery and performance of this
      Agreement. Upon execution and delivery, this Agreement will constitute a
      valid and binding obligation of Company enforceable against Company in
      accordance with its terms, except as such enforceability may be limited by
      applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent
      transfer, liquidation or similar laws relating to, or affecting generally,
      the enforcement of creditor's rights and remedies or by other equitable
      principles of general application from time to time in
effect.
	
            	 
	8.	
            	TAX ADVICE. Company acknowledges that Company has
      not relied and will not rely upon Geron or Geron’s counsel with respect to
      any tax consequences related to the ownership, purchase, or disposition of
      the Shares. Company assumes full responsibility for all such consequences
      and for the preparation and filing of all tax returns and elections which
      may or must be filed in connection with the
Shares.


    

     

    
      

    

    
    

     

    
      	9.	      	NOTICES. Any notice, demand or other
      communication required or permitted hereunder shall be in writing and
      shall be deemed to have been duly given on the date of delivery if
      delivered personally or by facsimile, or one day, not including Saturdays,
      Sundays, or national holidays, after sending if sent by national overnight
      delivery service, or five days, not including Saturdays, Sundays, or
      national holidays, after mailing if mailed by first class United States
      mail, certified or registered with return receipt requested, postage
      prepaid, and addressed as follows:


    

     

    
      	To Geron at:	
            	Geron Corporation
	
            	
            	230 Constitution Drive
	
            	
            	Menlo Park, California
94025
	
            	
            	Attention: Senior Director,
    Legal
	
            	
            	Telephone:	      	(650) 473-7700
	
            	
            	Facsimile:	
            	(650) 473-7750
	 
	To Company at:	
            	Prime Synthesis, Inc.
	
            	     	2 New Road, Suite 126
	
            	
            	Aston PA 19014
	 	
            	Attention: David H. Eyler, Chief
      Executive Officer
	
            	 	Telephone:	 	610.558.5920 ext. 110
	
            	
            	Facsimile:	
            	610.558.5923


    

      

    
      	10.	      	BINDING EFFECT. This Agreement shall be binding upon the
      heirs, legal representatives and successors of Geron and of Company;
      provided, however, that Company may not assign any rights or obligations
      under this Agreement. Geron may not assign any of its rights or
      obligations under this Agreement.
	 
	11.	
            	GOVERNING LAW. This Agreement shall be governed by and
      construed in accordance with the laws of the State of
  California.
	 
	12.	
            	INVALID PROVISIONS. In the event that any provision of this
      Agreement is found to be invalid or otherwise unenforceable by a court or
      other tribunal of competent jurisdiction, such invalidity or
      unenforceability shall not be construed as rendering any other provision
      contained herein invalid or unenforceable, and all such other provisions
      shall be given full force and effect to the same extent as though the
      invalid and unenforceable provision was not contained herein.
	 
	13.	
            	COUNTERPARTS. This Agreement may be executed in any
      number of identical counterparts, each of which shall be deemed an
      original, but all of which together shall constitute one and the same
      instrument.
	 
	14.	
            	AMENDMENTS. This Agreement or any provision hereof
      may be changed, waived, or terminated only by a statement in writing
      signed by the party against whom such change, waiver or termination is
      sought to be enforced.
	 
	15.	
            	FUTURE COOPERATION. Each of the parties hereto agrees to
      cooperate at all times from and after the date hereof with respect to all
      of the matters described herein, and to execute such further assignments,
      releases, assumptions, amendments of the Agreement, notifications and
      other documents as may be reasonably requested for the purpose of giving
      effect to, or evidencing or giving notice of, the transactions
      contemplated by this Agreement.
	 
	16.	
            	ENTIRE AGREEMENT. This Agreement and the Lease Agreement,
      as amended by the First Amendment, constitute the entire agreement of the
      parties pertaining to the Shares and supersede all prior and
      contemporaneous agreements, representations, and understandings of the
      parties with respect thereto.


    

     

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         IN WITNESS WHEREOF, the parties hereto have executed this Common Stock
Purchase Agreement as of the date first above written.

     

    
      	Geron Corporation
	  
	/s/ David L.
      Greenwood	 
	By:	     	David L. Greenwood
	Title:	
            	Executive Vice President and
    Chief
	
            	
            	Financial
      Officer
	  
	Company
	 
	/s/ David H.
    Eyler	 
	By:	
            	David H. Eyler
	Title:	
            	Chief Executive
  Officer