Onto Innovation Inc — Current Report (Form 8-K)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 18, 2026

Onto Innovation Inc.

(Exact name of Registrant as Specified in Its Charter)

(978) 253-6200

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 8.01 Other Events

On May 18, 2026, Onto Innovation Inc. (the “Company”) issued a press release announcing that the Company plans to commence, subject to market conditions and other factors, a private offering (the “Offering”) of $1,100,000,000 aggregate principal amount of convertible senior notes due 2031 (the “Notes”) to persons reasonably believed to be qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933 (the “Securities Act”). A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”) and is incorporated herein by reference.

Neither this Current Report on Form 8-K nor the press release attached hereto as Exhibit 99.1 constitutes an offer to sell, or the solicitation of an offer to buy, any securities.

Forward-Looking Statements

This Current Report on Form 8-K contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 (the “Act”) which include statements relating to the Notes offering, statements regarding the timing, size and completion of the proposed Notes offering, the intended use of proceeds, including the concurrent share repurchases and the capped call transactions, the terms of the Notes being offered, the effect of the share repurchases and the anticipated terms of, and the effects of entering into, the capped call transactions and the actions of the option counterparties and their respective affiliates, as well as other matters that are not purely historical data. The Company wishes to take advantage of the “safe harbor” provided for by the Act and cautions that actual results may differ materially from those projected as a result of various factors, including risks and uncertainties, many of which are beyond the Company’s control. Such factors include, but are not limited to, the Company’s ability to leverage its resources to improve its position in its core markets; its ability to weather difficult economic environments; its ability to open new market opportunities and target high-margin markets; the strength/weakness of the back-end and/or front-end semiconductor market segments; fluctuations in customer capital spending; the Company’s ability to effectively manage its supply chain and adequately source components from suppliers to meet customer demand; the effects of political, economic, legal, and regulatory changes, including tariffs and trade disputes, or conflicts on the Company’s global operations; its ability to adequately protect its intellectual property rights and maintain data security; its ability to effectively maneuver global trade issues and changes in trade and export regulations, tariffs and license policies; the Company’s ability to maintain relationships with its customers and manage appropriate levels of inventory to meet customer demands; the Company’s ability to realize the anticipated benefits of the proposed Notes offering and the capped call transactions on the timing expected or at all; the Company’s timing and ability to repay its debt; and the Company’s ability to successfully integrate acquired businesses and technologies. Additional information and considerations regarding the risks faced by the Company are available in the Company’s Annual Report on Form 10-K for the fiscal year ended January 3, 2026, as filed with the SEC on February 24, 2026, and its Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 as filed with the SEC on May 5, 2026. As the forward-looking statements are based on the Company’s current expectations, the Company cannot guarantee any related future results, levels of activity, performance or achievements. The Company does not assume any obligation to update the forward-looking information contained in this Current Report on Form 8-K, except as required by law. Neither future distribution of this Current Report on Form 8-K nor the continued availability of this Current Report on Form 8-K should be deemed to constitute an update or re-affirmation of these statements as of any future date.

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Item 9.01 Financial Statements and Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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