X0306 4 2013-08-01 0 0001262039 FORTINET INC FTNT 0001475586 Xie Michael C/O FORTINET, INC. 1090 KIFER ROAD SUNNYVALE CA 94086 1 1 0 0 VP, Engineering & CTO Common Stock 2012-12-03 5 G 0 120000 0 D 6628000 D Common Stock 2013-04-04 5 G 0 875398 0 D 1465657 I See footnote Common Stock 2013-04-04 5 G 0 875398 0 D 1465657 I See footnote Common Stock 2013-04-04 5 G 0 1750796 0 A 3068686 I See footnote Common Stock 2013-08-01 4 M 0 4166 0 A 6632166 D Common Stock 2013-08-01 4 F 0 1566 21.34 D 6630600 D Restricted Stock Units 0 2013-08-01 4 M 0 4166 0 D Common Stock 4166 12501 D Shares held directly by the Michael Xie Grantor Retained Annuity Trust dated February 9, 2011, for which the Reporting Person serves as a trustee. Shares held directly by the Danke Wu Grantor Retained Annuity Trust dated February 9, 2011, for which the Reporting Person serves as a trustee. Shares held directly by the 2010 K.A. Family Trust dated May 3, 2010, for which the Reporting Person serves as a trustee. Vesting of restricted stock units ("RSUs") granted to the Reporting Person on August 8, 2012. 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 in this Form 4 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 Reporting Person did not sell or otherwise dispose of any of the shares reported on this Form 4 for any reason other than to cover required taxes. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs vest on August 1, 2013, 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/ Robert Turner, by power of attorney 2013-08-02