ONTO INNOVATION INC.

On May 21, 2026 we issued the 2031 Notes to the initial purchasers in reliance upon Section 4(a)(2) of the Securities Act, for an aggregate offering price of $1.5 billion, in transactions not involving any public offering. The 2031 Notes were resold by the initial purchasers to persons whom the initial purchasers reasonably believe are “qualified institutional buyers” as defined in, and in accordance with, Rule 144A under the Securities Act. Any shares of Common Stock that may be issued upon conversion of the 2031 Notes will be issued in reliance upon Section 3(a)(9) of the Securities Act as involving an exchange by us exclusively with our security holders. Initially, a maximum of 5,893,200 shares of Common Stock may be issued upon conversion of the 2031 Notes, based on the maximum conversion rate of 3.9288 shares of Common Stock per $1,000 principal amount of 2031 Notes, which is subject to customary anti-dilution adjustment provisions.

For further information, see Note 7, “Debt Obligations,” of the Notes to the Condensed Consolidated Financial Statements.

In February 2024, the Board approved a share repurchase authorization (the “2024 Authorization”), which allowed the Company 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 six months ended June 30, 2026, no shares of the Company’s common stock were repurchased under the 2024 Authorization. During the three and six months ended June 28, 2025, no shares, and 492 thousand shares, respectively, of the Company’s common stock were repurchased under the 2024 Authorization. At June 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 six months ended June 30, 2026, 805 thousand shares of the Company’s common stock were repurchased under the 2026 Authorization. The 2026 Authorization ceases 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 June 30, 2026 (in thousands, except per share data):