X0306 4 2015-09-01 0 0001262039 FORTINET INC FTNT 0001288241 DEL MATTO ANDREW H C/O FORTINET, INC. 899 KIFER ROAD SUNNYVALE CA 94086 0 1 0 0 Chief Financial Officer Common Stock 2015-09-01 4 S 0 3250 41.3177 D 11533 D The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on March 10, 2015. Represents the aggregate of sales effected on the same day at different prices. Represents the weighted average sales price per share. The shares sold at prices ranging from $41.03 to $41.685 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Includes shares previously acquired by the Reporting Person under the Issuer's employee stock purchase plan on August 14, 2015. /s/ John Whittle, by power of attorney 2015-09-02