FTNTFortinet

On August 31, 2026, Janet Napolitano, one of our directors, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Napolitano Plan”) during an open trading window in accordance with our insider trading policy. The Napolitano Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Napolitano Plan provides for the potential sale by Ms. Napolitano of up to 390 shares of our common stock, plus up to 60% of the additional net shares (the number of which is not yet determinable) remaining after shares are withheld to satisfy tax obligations upon vesting and settlement of RSUs, in each case, at prices determined in accordance with the terms of the Napolitano Plan, all between November 30, 2026 and December 3, 2027. The Napolitano Plan includes a representation from Ms. Napolitano to the broker administering the plan that she was not in possession of any material nonpublic information regarding us or the securities subject to the Napolitano Plan at the time that she entered into the Napolitano Plan. She made a similar representation to us in connection with the adoption of the Napolitano Plan under our insider trading policy. The representation was made as of August 31, 2026, and speaks only as of that date. In making the representation, Ms. Napolitano did not provide assurance with respect to any material nonpublic information of which she was unaware, or with respect to any material nonpublic information acquired by her or us after the date of the representation. Once executed, transactions under the Napolitano Plan will be disclosed publicly through Form 4 and/or Form 144 filings with the SEC in accordance with applicable securities laws, rules and regulations. Except as may be required by law, we do not undertake any obligation to update or report any modification, termination, or other activity under current or future Rule 10b5-1 plans that may be adopted by Ms. Napolitano or our other officers or directors, or their affiliated entities.

On June 10, 2026, Christiane Ohlgart, our Chief Financial Officer, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Ohlgart Plan”) during an open trading window in accordance with our insider trading policy. The Ohlgart Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Ohlgart Plan provides for the potential sale by Mrs. Ohlgart of up to 115 shares of our common stock, plus a number of additional net shares (which is not yet determinable) remaining after shares are withheld to satisfy tax obligations upon vesting and settlement of RSUs and PSUs, in each case, at prices determined in accordance with the terms of the Ohlgart Plan, all between September 9, 2026 and September 15, 2027.

On June 5, 2026, John Whittle, our Chief Operating Officer, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Whittle Plan”) during an open trading window in accordance with our insider trading policy. The Whittle Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Whittle Plan provides for the potential sale by Mr. Whittle of up to 56,700 shares of our common stock, issued upon the exercise of vested stock options for shares of our common stock, at prices at or above a minimum price specified in the Whittle Plan, all between September 4, 2026 and September 30, 2027.

On March 4, 2026, Michael Xie, our Chief Technology Officer and one of our directors, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Michael Xie Plan”) during an open trading window in accordance with our insider trading policy. The Michael Xie Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Michael Xie Plan provides for the potential sale by Mr. Michael Xie of up to (a) 466,239 shares of our common stock, issued upon the vesting and settlement of RSUs for shares of our common stock and the exercise of vested options to purchase shares of our common stock and (b) the net shares (which are not yet determinable) after shares are withheld to satisfy tax obligations upon such vesting and settlement of RSUs and PSUs, in each case, at the market price, all between June 3, 2026 and November 30, 2027.

On March 3, 2026, Ken Xie, our Chief Executive Officer and one of our directors, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Ken Xie Plan”) during an open trading window in accordance with our insider trading policy. The Ken Xie Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Ken Xie Plan provides for the potential sale by Mr. Ken Xie of up to (a) 1,164,981 shares of our common stock, issued upon the vesting and settlement of RSUs for shares of our common stock and the exercise of vested options to purchase shares of our common stock and (b) the net shares (which are not yet determinable) after shares are withheld to satisfy tax obligations upon such vesting and settlement of RSUs and PSUs, in each case, at the market price, all between June 2, 2026 and November 30, 2027.

On February 19, 2026, John Whittle, our Chief Operating Officer, modified an existing trading plan, which was originally adopted on March 3, 2025 in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Whittle Plan”) during an open trading window in accordance with our insider trading policy. The modified Whittle Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The modified Whittle Plan provides for the potential sale by Mr. Whittle of up to 146,015 shares of our common stock, issued upon the exercise of vested stock options for shares of our common stock, at the market price, between May 21, 2026 and May 28, 2027.

As previously reported, our former Chief Financial Officer, Keith Jensen, retired on May 15, 2025. In connection with Mr. Jensen’s retirement, his pre-arranged written stock sale plan for the sale of shares of our common stock adopted on March 6, 2024 was terminated.

On March 7, 2025, Margrit Christiane Ohlgart, our Chief Accounting Officer, entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 under the Exchange Act for the sale of shares of our common stock (the “Ohlgart Plan”) during an open trading window in accordance with our insider trading policy. The Ohlgart Plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The Ohlgart Plan provides for the potential sale by Mrs. Ohlgart of net shares (which are not yet determinable) after shares are withheld to satisfy tax obligations upon vesting and settlement of RSUs and PSUs, in each case, at the market price, all between June 6, 2025 and September 5, 2026.