Fortinet (FTNT) 4: Director vests 459 RSUs, no sale (Oct 1, 2026)

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-09-30 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: Fortinet, Inc. (FTNT) CIK: 0001262039 --- Reporting Owner --- Name: STAVRIDIS JAMES G. CIK: 0001661859 Role: Director --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-09-30 | Code: M (Exercise of derivative) Shares: +459 | Price: $0.00 Shares Owned After: 17,648 | Ownership: D (Direct) Footnotes: [F1] Vesting of restricted stock units ("RSUs") granted to the Reporting Person on August 12, 2026. --- Derivative Transactions --- [Transaction #1] Security: Restricted Stock Units Date: 2026-09-30 | Code: M (Exercise of derivative) Shares: -459 | Price: $0.00 Exercise Price: $0.00 Shares Owned After: 1,377 | Ownership: D (Direct) Footnotes: [F2] Each RSU represents a contingent right to receive one share of the Issuer's common stock upon settlement. [F1] Vesting of restricted stock units ("RSUs") granted to the Reporting Person on August 12, 2026. [F3] The RSUs will vest in substantially equal increments on each of September 30, 2026, December 31, 2026, March 31, 2027, and the earlier of (i) June 30, 2027 and (ii) the date immediately preceding the Issuer's 2027 annual meeting of stockholders, subject to the Reporting Person's provision of services to the Issuer on each vesting date. Shares of the Issuer's Common Stock will be delivered to the Reporting Person following vesting. [F4] RSUs do not expire; they either vest or are canceled prior to vest date. --- Footnotes (Complete Index) --- F1: Vesting of restricted stock units ("RSUs") granted to the Reporting Person on August 12, 2026. F2: Each RSU represents a contingent right to receive one share of the Issuer's common stock upon settlement. F3: The RSUs will vest in substantially equal increments on each of September 30, 2026, December 31, 2026, March 31, 2027, and the earlier of (i) June 30, 2027 and (ii) the date immediately preceding the Issuer's 2027 annual meeting of stockholders, subject to the Reporting Person's provision of services to the Issuer on each vesting date. Shares of the Issuer's Common Stock will be delivered to the Reporting Person following vesting. F4: RSUs do not expire; they either vest or are canceled prior to vest date. --- Signature --- /s/ /s/ Robert Turner, by power of attorney (2026-10-01)