Fortinet, Inc. — Director's Dealing 2017

May 3, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: FORTINET INC (FTNT)
CIK: 0001262039
Period of Report: 2017-05-01

Reporting Person: Xie Michael (Director, VP, Engineering & CTO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-05-01	Common Stock	M	2500	—	Acquired	6714500	Direct
2017-05-01	Common Stock	M	2500	—	Acquired	6717000	Direct
2017-05-01	Common Stock	M	2500	—	Acquired	6719500	Direct
2017-05-01	Common Stock	A	22500	—	Acquired	6742000	Direct
2017-05-01	Common Stock	F	15656	$39.15	Disposed	6726344	Direct
2017-05-02	Common Stock	S	14344	$39.4256	Disposed	6712000	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-05-01	Restricted Stock Units	$0	M	2500	Disposed		Common Stock (2500)	Direct
2017-05-01	Restricted Stock Units	$0	M	2500	Disposed		Common Stock (2500)	Direct
2017-05-01	Restricted Stock Units	$0	M	2500	Disposed		Commn Stock (2500)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	1632913	Indirect
Common Stock	1632913	Indirect
Common Stock	1991686	Indirect
Common Stock	462488	Indirect

Footnotes

F1: Vesting of restricted stock units ("RSUs") granted to the Reporting Person on February 12, 2014.

F2: Vesting of RSUs granted to the Reporting Person on February 11, 2015.

F3: Vesting of RSUs granted to the Reporting Person on February 11, 2016.

F4: Represents shares earned by the Reporting Person as a result of the vesting of performance stock units ("PSUs") granted to the Reporting Person on May 7, 2014.

F5: 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 line 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 and PSUs.

F6: The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on August 12, 2016.

F7: Represents the aggregate of sales effected on the same day at different prices

F8: Represents the weighted average sales price per share. The shares sold at prices ranging from $39.16 to $39.69 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.

F9: Shares held directly by the 2014 Michael Xie Grantor Retained Annuity Trust dated March 6, 2014, for which the Reporting Person serves as a trustee.

F10: Shares held directly by the 2014 Danke Wu Grantor Retained Annuity Trust dated March 6, 2014, for which the Reporting Person serves as a trustee.

F11: Shares held directly by the 2010 K.A. Family Trust dated May 3, 2010, for which the Reporting Person serves as a trustee.

F12: Shares held directly by The K.A. Children's Trust dated February 9, 2011, for which the Reporting Person serves as a trustee.

F13: Each RSU represents a contingent right to receive one share of the Issuer's common stock.

F14: 25% of the RSUs vest 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.

F15: 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.

F16: 25% of the RSUs vest on February 1, 2017, 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.