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SANGAMO BIOSCIENCES, INC.
2000 EMPLOYEE STOCK PURCHASE PLAN
I. Purpose of the Plan
This Employee Stock Purchase Plan is intended to promote the interests of Sangamo BioSciences, Inc., a Delaware
corporation, by providing eligible employees with the opportunity to acquire a proprietary interest in the Corporation through
participation in a payroll deduction-based employee stock purchase plan designed to qualify under Section 423 of the Code.
Capitalized terms herein shall have the meanings assigned to such terms in the attached Appendix.
II. Administration of the Plan
The Plan Administrator shall have full authority to interpret and construe any provision of the Plan and to adopt such rules
and regulations for administering the Plan as it may deem necessary in order to comply with the requirements of Code
Section 423. Decisions of the Plan Administrator shall be final and binding on all parties having an interest in the Plan.
III. Stock Subject to Plan
A. The stock purchasable under the Plan shall be shares of authorized but unissued or reacquired Common Stock,
including shares of Common Stock purchased on the open market. The number of shares of Common Stock initially reserved for
issuance over the term of the Plan shall be limited to 400,000 shares.
B. The number of shares of Common Stock available for issuance under the Plan shall automatically increase on the first
trading day of the second fiscal quarter of each fiscal year of the Corporation during the term of the Plan, beginning with fiscal
year 2001, by an amount equal to one percent (1%) of the total number of shares of Common Stock outstanding on the last
trading day in the immediately preceding first fiscal quarter, but in no event shall any such annual increase exceed 600,000
C. Should any change be made to the Common Stock by reason of any stock split, stock dividend,