Exhibit 10.10

NOTE: Portions of this Exhibit are the subject of a Confidential Treatment
Request by the Registrant to the Securities and Exchange Commission (the
“Commission”). Such portions have been redacted and are marked with a “[***]” in
the place of the redacted language. The redacted information has been filed
separately with the Commission.

THIRD AMENDMENT

This Amendment with the Effective Date of September 1, 1999 is to the License
Agreement dated May 9, 1996 between Sangamo BioSciences, Inc. and Massachusetts
Institute of Technology, which was amended on December 10, 1997, and on
December 2, 1998.

The parties thereto now further agree as follows:

 

1. M.I.T. Case No. 8528H, “Dimerization Of Zinc Fingers Mediated By Peptides
Evolved In Vitro From Random Sequences”, by Carl O. Pabo And Bryan S. Wang shall
be added to the PATENT RIGHTS. The license granted hereunder shall be exclusive
in all fields of use.

 

2. In consideration of the license granted hereunder

 

  (a) LICENSEE shall pay M.I.T. an Amendment Issue Fee of:

 

  (i) [***] dollars ($[***]) due upon signing; and

 

  (ii) [***] dollars ($[***]) due upon issuance of the first claims of any
M.I.T. Case 8528H patent.

 

  (b) The License Maintenance Fees due under Paragraph 4.1(b) shall be increased
by [***] dollars ($[***]) to [***] dollars ($[***]) on January 1, 2000 and [***]
($[***]) on January 1, 2001 and beyond.

 

  (c) The Sublicense Maintenance Fees due under Paragraph 4.1 (h) shall be
increased to [***] dollars ($[***]) per year per sublicense. The sublicense
issue fee shall not increase.

 

  (d) LICENSEE shall be responsible for payment of all fees and costs relating
to the filing, prosecution and maintenance of M.I.T. Case No. 8528H whether such
fees and costs were incurred before or after the effective date of this
Amendment.

3.

 

  (a) LICENSEE shall have the primary responsibility for filing, prosecution and
maintenance of the M.I.T. Case No. 8528H patents and patent applications.
LICENSEE shall seek broad claims in M.I.T.’s best interest and shall not abandon
any major claim without prior written permission from M.I.T., such permission
not to be unreasonably withheld.

 

  (b)

Notwithstanding any other provisions of this Agreement, LICENSEE shall not
abandon the prosecution of M.I.T. Case No. 8528H patents or patent applications

 

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*** CONFIDENTIAL PORTIONS OMITTED AND FILED SEPARATELY WITH THE COMMISSION

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

 

(except for purposes of filing a continuation application) without prior written
notice to M.I.T. at least sixty (60) days prior to the date on which any pending
Patent Office actions need to be taken. Upon receiving such written notice,
M.I.T. may, at its sole option and expense, take over prosecution of any such
M.I.T. patents or patent applications. Thereafter, this Agreement shall
terminate as to such M.I.T. patents or patent applications.

 

  (c) LICENSEE shall send copies of all correspondence concerning patent
prosecution to M.I.T.

All other terms and conditions as set forth in the Agreement.

Agreed to for:

 

MASSACHUSETTS INSTITUTE OF TECHNOLOGY     SANGAMO BIOSCIENCES, INC. By  

/s/ Lita Nelson

    By  

/s/ Peter Bluford

Name  

Lita L. Nelson

    Name  

Peter Bluford

Title  

Director, Technology Licensing Office

    Title  

Vice President, Corporate Development

Date  

August 19, 1999

    Date  

September 1, 1999

 

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