X0306 4 2018-11-27 0 0001001233 SANGAMO THERAPEUTICS, INC SGMO 0001755198 Boissel Stephane C/O SANGAMO THERAPEUTICS, INC. POINT RICHMOND TECH CTR, 501 CANAL BLVD. RICHMOND CA 94804 0 1 0 0 EVP, Corp. Strat. & Int. CFO Free Shares Call Options (obligation to sell to Issuer) 2018-11-27 4 J 0 4 0.00 D 2019-05-03 2020-12-02 Common Stock 4 D Free Shares Put Options (right to sell to Issuer) 2018-11-27 4 J 0 4 0.00 A 2019-07-04 2021-02-03 Common Stock 4 D In connection with the acquisition by the Issuer of Sangamo Therapeutics France S.A.S. (formerly TxCell S.A.) ("Sangamo France"), the Reporting Person granted to the Issuer the right to purchase up to 238,100 "free shares" of Sangamo France (the "Subject Free Shares") for cash in four separate tranches beginning May 3, 2019 (the "Free Shares Call Options"). The exercise price per Subject Free Share to be paid by the Issuer upon exercise of its Free Shares Call Options is equal to the product of 2.58 euros times the quotient of the 20-day volume weighted average price of the Issuer's common stock preceding the date the Issuer notifies the Reporting Person of its exercise of its Free Shares Call Options (as converted to euros) divided by 12.8329. In connection with the acquisition by the Issuer of Sangamo France, in addition to the grant to the Issuer of the Free Shares Call Options, the Reporting Person was granted the right to sell to the Issuer the Subject Free Shares for cash in four separate tranches beginning July 4, 2019 (the "Free Shares Put Options"), which Free Shares Put Options shall be exercisable to the extent that the corresponding Free Shares Call Options are not exercised by the Issuer. The exercise price per Subject Free Share to be paid by the Issuer upon the Reporting Person's exercise of its Free Shares Put Options is equal to the product of 2.58 euros times the quotient of the 20-day volume weighted average price of the Issuer's common stock preceding the date the Reporting Person notifies the Issuer of his exercise of his Free Shares Put Options (as converted to euros) divided by 12.8329. /s/ Matthew Colvin, Attorney-in-Fact for Stephane Boissel 2019-08-14