ONTO INNOVATION INC.

In February 2024, the Onto Innovation Board of Directors (the “Board”) approved a share repurchase authorization (the “2024 Authorization”), which allows us to repurchase up to $200 million worth of shares of Common Stock. Under the 2024 Authorization, repurchases may be made through both public market and private transactions from time to time. Any amount paid to repurchase the shares in excess of par value, including transaction costs, would be recorded directly as a decrease to additional paid-in capital. During the three and nine month periods ended September 30, 2026, no shares of Common Stock were repurchased under the 2024 Authorization. During the three and nine months ended September 27, 2025, no shares and 492 thousand shares, respectively, of Common Stock were repurchased under the 2024 Authorization. At September 30, 2026, there was $99.9 million available for future share repurchases under the 2024 Authorization.

Additionally, in May 2026, the Board approved a share repurchase authorization (the “2026 Authorization”), which allowed the Company to repurchase up to $300 million worth of shares of Common Stock solely in connection with the 2031 Notes issuance. During the three and nine months ended September 30, 2026, no shares and 805 thousand shares, respectively, of Common Stock were repurchased under the 2026 Authorization. The 2026 Authorization ceased to be in effect and any and all remaining and unused amount under the 2026 Authorization is no longer available for repurchase.

For further information, see Note 14, “Share Repurchase Authorization,” of the Notes to the Condensed Consolidated Financial Statements.

In addition to our share repurchase program, we withhold shares of Common Stock associated with net share settlements to cover tax withholding obligations upon the vesting of restricted stock unit awards under the Company’s equity incentive program.

The following table provides details of Common Stock purchased during the three months ended September 30, 2026 (in thousands, except per share data):