X0306 4 2016-08-01 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 2016-08-01 4 M 0 7500 0 A 22099 D Common Stock 2016-08-01 4 M 0 1875 0 A 23974 D Common Stock 2016-08-01 4 F 0 4893 34.85 D 19081 D Common Stock 2016-08-02 4 S 0 5500 34.0707 D 13581 D Restricted Stock Units 0 2016-08-01 4 M 0 7500 0 A Common Stock 7500 45000 D Restricted Stock Units 0 2016-08-01 4 M 0 1875 0 A Common Stock 1875 18750 D Vesting of restricted stock units ("RSUs") granted to the Reporting Person on February 12, 2014. Vesting of RSUs granted to the Reporting Person on February 11, 2015. Exempt transaction pursuant to Section 16b-3(e) - payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3. All of the shares reported as disposed of on this row were relinquished by the Reporting Person and cancelled by the Issuer in exchange for the Issuer's agreement to pay federal and state tax withholding obligations of the Reporting Person resulting from the vesting of RSUs. The price per share was based on the fair market value of the Issuer's common stock on the vesting and release date. 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 $33.73 to $34.71 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. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs vested on February 1, 2015, then the remaining 75% of the RSUs vest in equal installments on each quarterly anniversary thereafter, until such time as the RSUs are 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. Shares of the Issuer's common stock will be delivered to the Reporting Person upon vesting. 25% of the RSUs vest on February 1, 2016, then the remaining 75% of the RSUs vest in equal installments on each quarterly anniversary thereafter, until such time as the RSUs are 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. Shares of the Issuer's common stock will be delivered to the Reporting Person upon vesting. /s/ John Whittle, by power of attorney 2016-08-03