X0306 4 2022-02-24 0 0001262039 Fortinet, Inc. FTNT 0001418649 Jensen Keith C/O FORTINET, INC. 899 KIFER ROAD SUNNYVALE CA 94086 0 1 0 0 CFO & Chief Accounting Officer Common Stock 2022-02-24 4 M 0 2501 49.06 A 3384 D Common Stock 2022-02-24 4 M 0 2947 84.49 A 6331 D Common Stock 2022-02-24 4 M 0 2547 114.48 A 8878 D Common Stock 2022-02-24 4 M 0 9585 171.93 A 18463 D Common Stock 2022-02-24 4 S 0 600 277.6517 D 17863 D Common Stock 2022-02-24 4 S 0 369 279.6223 D 17494 D Common Stock 2022-02-24 4 S 0 415 282.0877 D 17079 D Common Stock 2022-02-24 4 S 0 300 283.41 D 16779 D Common Stock 2022-02-24 4 S 0 100 285.15 D 16679 D Common Stock 2022-02-24 4 S 0 200 287.37 D 16479 D Common Stock 2022-02-24 4 S 0 200 288.34 D 16279 D Common Stock 2022-02-24 4 S 0 800 290.39 D 15479 D Common Stock 2022-02-24 4 S 0 200 290.885 D 15279 D Common Stock 2022-02-24 4 S 0 172 293.6326 D 15107 D Common Stock 2022-02-24 4 S 0 300 295.35 D 14807 D Common Stock 2022-02-24 4 S 0 800 296.83 D 14007 D Common Stock 2022-02-24 4 S 0 606 297.6608 D 13401 D Common Stock 2022-02-24 4 S 0 100 300.09 D 13301 D Common Stock 2022-02-24 4 S 0 600 301.4733 D 12701 D Common Stock 2022-02-24 4 S 0 1200 302.5267 D 11501 D Common Stock 2022-02-24 4 S 0 700 303.9414 D 10801 D Common Stock 2022-02-24 4 S 0 500 304.964 D 10301 D Common Stock 2022-02-24 4 S 0 1724 305.9202 D 8577 D Common Stock 2022-02-24 4 S 0 600 306.8517 D 7977 D Common Stock 2022-02-24 4 S 0 298 307.8313 D 7679 D Common Stock 2022-02-24 4 S 0 500 308.944 D 7179 D Common Stock 2022-02-24 4 S 0 443 310.5711 D 6736 D Common Stock 2022-02-24 4 S 0 500 311.672 D 6236 D Common Stock 2022-02-24 4 S 0 611 312.3389 D 5625 D Common Stock 2022-02-24 4 S 0 1615 313.6812 D 4010 D Stock Option (right to buy) 49.06 2022-02-24 4 M 0 2501 0.00 D 2025-02-20 Common Stock 2501 0 D Stock Option (right to buy) 84.49 2022-02-24 4 M 0 2947 0.00 D 2026-02-21 Common Stock 2947 11784 D Stock Option (right to buy) 114.48 2022-02-24 4 M 0 2547 0.00 D 2027-02-21 Common Stock 2547 20370 D Stock Option (right to buy) 171.93 2022-02-24 4 M 0 9585 0.00 D 2028-02-19 Common Stock 9585 28758 D The reported transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person. Represents the weighted average sale price. The lowest price at which shares were sold was $277.51 and the highest price at which shares were sold was $278.20. The Reporting Person undertakes to provide upon request to the staff of the Securities and Exchange Commission, the Issuer or its stockholders, full information regarding the total number of shares sold at each separate price within the ranges set forth in footnotes (2) through (25) to this Form 4. Represents the weighted average sale price. The lowest price at which shares were sold was $279.27 and the highest price at which shares were sold was $280.00. Represents the weighted average sale price. The lowest price at which shares were sold was $281.76 and the highest price at which shares were sold was $282.36. Represents the weighted average sale price. The lowest price at which shares were sold was $283.32 and the highest price at which shares were sold was $283.59. Represents the weighted average sale price. The lowest price at which shares were sold was $287.13 and the highest price at which shares were sold was $287.61. Represents the weighted average sale price. The lowest price at which shares were sold was $288.24 and the highest price at which shares were sold was $288.44. Represents the weighted average sale price. The lowest price at which shares were sold was $289.84 and the highest price at which shares were sold was $290.79. Represents the weighted average sale price. The lowest price at which shares were sold was $290.85 and the highest price at which shares were sold was $290.92. Represents the weighted average sale price. The lowest price at which shares were sold was $293.15 and the highest price at which shares were sold was $293.98. Represents the weighted average sale price. The lowest price at which shares were sold was $295.02 and the highest price at which shares were sold was $295.58. Represents the weighted average sale price. The lowest price at which shares were sold was $296.18 and the highest price at which shares were sold was $297.14. Represents the weighted average sale price. The lowest price at which shares were sold was $297.21 and the highest price at which shares were sold was $298.08. Represents the weighted average sale price. The lowest price at which shares were sold was $301.10 and the highest price at which shares were sold was $302.06. Represents the weighted average sale price. The lowest price at which shares were sold was $302.31 and the highest price at which shares were sold was $303.00. Represents the weighted average sale price. The lowest price at which shares were sold was $303.45 and the highest price at which shares were sold was $304.14. Represents the weighted average sale price. The lowest price at which shares were sold was $304.52 and the highest price at which shares were sold was $305.46. Represents the weighted average sale price. The lowest price at which shares were sold was $305.52 and the highest price at which shares were sold was $306.42. Represents the weighted average sale price. The lowest price at which shares were sold was $306.52 and the highest price at which shares were sold was $307.50. Represents the weighted average sale price. The lowest price at which shares were sold was $307.63 and the highest price at which shares were sold was $308.06. Represents the weighted average sale price. The lowest price at which shares were sold was $308.68 and the highest price at which shares were sold was $309.51. Represents the weighted average sale price. The lowest price at which shares were sold was $310.07 and the highest price at which shares were sold was $310.75. Represents the weighted average sale price. The lowest price at which shares were sold was $311.11 and the highest price at which shares were sold was $311.88. Represents the weighted average sale price. The lowest price at which shares were sold was $312.13 and the highest price at which shares were sold was $312.89. Represents the weighted average sale price. The lowest price at which shares were sold was $313.23 and the highest price at which shares were sold was $314.13. 1/4 of the shares subject to the option vested on February 20, 2019 and 1/48 of the shares subject to the option will vest monthly thereafter, subject to the Reporting Person's provision of service to the Issuer on each vesting date. 1/4 of the shares subject to the option vested on February 21, 2020 and 1/48 of the shares subject to the option will vest monthly thereafter, subject to the Reporting Person's provision of service to the Issuer on each vesting date. 1/4 of the shares subject to the option will vest on February 21, 2021 and 1/48 of the shares subject to the option will vest monthly thereafter, subject to the Reporting Person's provision of service to the Issuer on each vesting date. 1/4 of the shares subject to the option will vest on February 19, 2022, and 1/48 of the shares subject to the option will vest monthly thereafter, subject to the Reporting Person's provision of service to the Issuer on each vesting date. This Form 4 is the first of two Forms 4 filed to report transactions by the Reporting Person that occurred on February 24, 2022. This Form 4 is split into two filings because the SEC's EDGAR filing system limits the number of transactions reported on a single Form 4. /s/ Robert Turner, by power of attorney 2022-02-28