8-K

ONTO INNOVATION INC.

Dated: May 21, 2026

/s/ Brian K. Roberts

Name: Brian K. Roberts

Title: Chief Financial Officer and Principal Accounting Officer

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)

Delaware

001-39110

94-2276314

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)


16 Jonspin Road
Wilmington, Massachusetts		01887
(Address of principal executive offices)		(Zip Code)

(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):

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, $0.001 par value per share	ONTO	New York Stock Exchange

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 1.01

Entry into a Material Definitive Agreement.

Indenture and Notes

On May 21, 2026, Onto Innovation Inc. (the “Company”) issued $1,500,000,000 aggregate principal amount of 0.00% Convertible Senior Notes due 2031 (the “Notes”). The Notes were issued pursuant to an Indenture, dated May 21, 2026 (the “Indenture”), between the Company and U.S. Bank Trust Company, National Association, as trustee (the “Trustee”). Pursuant to the purchase agreement between the Company and the representative of the initial purchasers of the Notes, the Company granted the initial purchasers an option to purchase, for settlement within a period of 13 days from, and including, the date the Notes are first issued, up to an additional $200,000,000 aggregate principal amount of Notes. On May 19, 2026, the initial purchasers exercised this option in full and the Notes issued on May 21, 2026 include the additional $200,000,000 aggregate principal amount of Notes.

The Company offered and sold the Notes to the initial purchasers in reliance on the exemption from registration provided by Section 4(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”), and for resale by the initial purchasers to persons reasonably believed to be qualified institutional buyers pursuant to the exemption from registration provided by Rule 144A under the Securities Act.

The Notes are the Company’s senior, unsecured obligations and rank equally in right of payment with the Company’s existing and future senior, unsecured indebtedness, rank senior in right of payment to the Company’s existing and future indebtedness that is expressly subordinated to the Notes in right of payment, effectively subordinated to any secured indebtedness to the extent of the value of the collateral securing such indebtedness, and structurally subordinated to all indebtedness and other liabilities, including trade payables, and (to the extent the Company is not a holder thereof) preferred equity, if any, of the Company’s subsidiaries.

The Notes will mature on June 1, 2031, unless earlier converted, redeemed or repurchased. The Notes will not bear regular interest, and the principal amount of the Notes will not accrete. However, special interest and additional interest, if any, may accrue on the Notes at a combined rate per annum not exceeding 0.50% upon the occurrence of certain events as described in the Indenture.

On or after March 1, 2031, until the close of business on the second Scheduled Trading Day (as defined in the Indenture) immediately before the maturity date, the Notes will be convertible at the option of the noteholders at any time.

Before March 1, 2031, noteholders will have the right to convert their Notes only under the following circumstances:

(1)

during any fiscal quarter (and only during such fiscal quarter) commencing after the fiscal quarter ending on September 30, 2026, if the Last Reported Sale Price (as defined in the Indenture) per share of the Company’s common stock, par value $0.001 per share (the “Common Stock”), exceeds 130% of the conversion price (as described below) for each of at least 20 Trading Days (as defined in the Indenture) (whether or not consecutive) during a period of 30 consecutive Trading Days ending on, and including, the last Trading Day of the immediately preceding fiscal quarter;

(2)

during the five consecutive business days immediately after any ten consecutive Trading Day period (the “Measurement Period”) in which the Trading Price (as defined in the Indenture) per $1,000 principal amount of Notes for each Trading Day of the Measurement Period was less than 98% of the product of the Last Reported Sale Price per share of the Common Stock on such Trading Day and the conversion rate (as described below) on each Trading Day;

(3)

upon the occurrence of specified corporate events or distributions on the Common Stock as set forth in the Indenture; or

(4)

if the Company calls such Notes for redemption.

The conversion rate for the Notes will initially be 2.6192 shares of Common Stock per $1,000 principal amount of Notes, which is equivalent to an initial conversion price of approximately $381.80 per share of Common Stock. The conversion rate is subject to adjustment upon certain events. Upon conversion, the Company will settle conversions by paying cash up to the aggregate principal amount of the Notes to be converted and paying or delivering, as the case may be, cash, shares of Common Stock or a combination of cash and shares of Common Stock, at its election, in respect of the remainder, if any, of its conversion obligation in excess of the aggregate principal amount of the Notes being converted, based on the applicable conversion rate(s).

The Company may not redeem the Notes at its option at any time before June 6, 2029. The Company will have the option to redeem the Notes, in whole or in part (subject to the partial redemption limitation described below), at any time, and from time to time, on or after June 6, 2029 and before the 31st Scheduled Trading Day immediately before the maturity date, at a cash redemption price equal to the principal amount of the Notes to be redeemed, plus accrued and unpaid special interest and additional interest, if any, to, but excluding, the redemption date, but only if the Last Reported Sale Price per share of the Common Stock exceeds 130% of the conversion price on (1) each of at least 20 Trading Days, whether or not consecutive, during the 30 consecutive Trading Days ending on, and including, the Trading Day immediately before the date the Company sends the related redemption notice; and (2) the Trading Day immediately before the date the Company sends such notice. In addition, calling any Note for redemption will constitute a Make-Whole Fundamental Change (as defined in the Indenture) with respect to that Note, in which case the conversion rate applicable to the conversion of that Note will be increased in certain circumstances if it is converted after it is called for redemption. Pursuant to the partial redemption limitation, the Company may not elect to redeem less than all of the outstanding Notes unless at least $100.0 million aggregate principal amount of Notes are outstanding and not subject to redemption as of the time it sends the related redemption notice.

If certain corporate events that constitute a Fundamental Change (as defined in the Indenture) occur, then, subject to certain exceptions, noteholders may require the Company to repurchase their Notes in whole or in part for cash at a price equal to the principal amount of the Notes to be repurchased, plus accrued and unpaid special interest and additional interest, if any, to, but excluding, the Fundamental Change Repurchase Date (as defined in the Indenture). The definition of Fundamental Change includes, among other things, certain business combination transactions involving the Company and certain de-listing events with respect to the Common Stock.

In addition, upon a Make-Whole Fundamental Change, the Company will, under certain circumstances, increase the applicable conversion rate for a holder that elects to convert its Notes in connection with such Make-Whole Fundamental Change. No adjustment to the conversion rate will be made if the Stock Price (as defined in the Indenture) in such Make-Whole Fundamental Change is either less than $254.53 per share or greater than $2,750.00 per share. The Company will not increase the conversion rate to an amount that exceeds 3.9288 shares per $1,000 principal amount of Notes, subject to adjustment as set forth in the Indenture.

The Notes will have customary provisions relating to the occurrence of Events of Default (as defined in the Indenture), which include the following:

(i)

certain payment defaults (which, in the case of a default in the payment of special interest or additional interest on the Notes, will be subject to a 30-day cure period);

(ii)

the Company’s failure to send certain notices under the Indenture within specified periods of time, subject to applicable cure periods;

(iii)

a default by the Company in its obligation to convert a Note in accordance with the Indenture if not cured within three business days after its occurrence;

(iv)

the Company’s failure to comply with certain covenants in the Indenture relating to the Company’s ability to consolidate with or merge with or into, or sell, lease or otherwise transfer, in one transaction or a series of transactions, all or substantially all of the assets of the Company and its subsidiaries, taken as a whole, to another person;

(v)

a default by the Company in its other obligations or agreements under the Indenture or the Notes if such default is not cured or waived within 60 days after notice is given in accordance with the Indenture;

(vi)

certain defaults by the Company or any of its Significant Subsidiaries (as defined in the Indenture) with respect to indebtedness for borrowed money of at least $175 million; and

(vii)

certain events of bankruptcy, insolvency and reorganization involving the Company or any of its Significant Subsidiaries.

If an Event of Default involving bankruptcy, insolvency or reorganization events with respect to the Company (and not solely with respect to a Significant Subsidiary), occurs, then the principal amount of, and all accrued and unpaid interest, if any, on, all of the then outstanding Notes will immediately become due and payable without any further action or notice by any person. If an of Event of Default (other than an Event of Default described in the immediately preceding sentence) occurs and is continuing, then, except as described in the immediately succeeding sentence, the Trustee, by notice to the Company, or the noteholders of at least 25% of the aggregate principal amount of the then outstanding Notes by notice to the Company and the Trustee, may declare the principal amount of, and all accrued and unpaid interest, if any, on, all of the then outstanding Notes to become due and payable immediately. Notwithstanding the foregoing the Company may elect, at its option, that the sole remedy for an Event of Default relating to certain failures by the Company to comply with certain reporting covenants in the Indenture will, for the first 365 days on which such an Event of Default has occurred and is continuing, consist exclusively of the right of noteholders to receive special interest on the Notes at a specified rate per annum not exceeding 0.50% on the principal amount of the Notes.

In certain circumstances if, at any time during the six-month period beginning on, and including, the date that is six months after the last date of original issuance of the Notes, the Company fails to timely file certain reports required to be filed with the SEC under the U.S. Securities Exchange Act of 1934, as amended, or the Notes are not otherwise Freely Tradable by holders of the Notes other than the Company’s affiliates, additional interest will accrue on the Notes during the period in which the Company’s failure to file has occurred and is continuing or such Notes are not otherwise Freely Tradable (as defined in the Indenture) by holders other than the Company’s affiliates.

In addition, if, and for so long as, the restrictive legend on the Notes has not been removed in accordance with the terms of the Indenture and the Notes, the Notes are assigned a restricted CUSIP number or the Notes are not otherwise Freely Tradable by holders other than the Company’s affiliates (without restrictions pursuant to U.S. securities laws or the terms of the Indenture or the Notes) as of the 15th day after the one-year anniversary of the last date of original issuance of the Notes, then additional interest will accrue on the Notes with respect to the period in which the Notes remain so restricted at a specified rate per annum not exceeding 0.50% on the principal amount of the Notes.

The above description of the Indenture and the Notes is a summary and is not complete. A copy of the Indenture and Form of Global Note are filed as Exhibits 4.1 and 4.2, respectively, to this Current Report on Form 8-K, and are incorporated herein by reference. This description is qualified in its entirety by reference to such documents.

Capped Call Transactions

On May 18, 2026 and May 19, 2026, in connection with the pricing of the Notes and the exercise by the initial purchasers of their option in full to purchase additional Notes, respectively, the Company entered into privately negotiated capped call transactions (the “Capped Call Transactions”) with one or more financial institutions, including one or more of the initial purchasers and/or their respective affiliates (the “Option Counterparties”).

The Capped Call Transactions cover, subject to anti-dilution adjustments substantially similar to those applicable to the Notes, the number of shares of Common Stock initially underlying the Notes. The Capped Call Transactions are expected generally to reduce the potential dilution to the Common Stock upon any conversion of the Notes and/or offset any potential cash payments the Company is required to make in excess of the principal amount of converted Notes, as the case may be, with such reduction and/or offset subject to a cap. The cap price of the Capped Call Transactions will initially be $509.06 per share of Common Stock, which represents a premium of 100% over the last reported sale price of the Common Stock of $254.53 per share on May 18, 2026, and is subject to certain adjustments under the terms of the Capped Call Transactions.

The Capped Call Transactions are separate transactions (in each case entered into by the Company with the Option Counterparties), are not part of the terms of the Notes and will not change the holders’ rights under the Notes. Holders will not have any rights with respect to the Capped Call Transactions.

The above description of the Capped Call Transactions is a summary and is not complete. A copy of the Form of Capped Call Confirmation is filed as Exhibit 10.1 to this Current Report on Form 8-K, and the above summary is qualified by reference to the full text of the Form of Capped Call Confirmation set forth in such exhibit.

Item 2.03

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The information set forth under Item 1.01 of this Current Report on Form 8-K is incorporated herein by reference.

Item 3.02

Unregistered Sales of Equity Securities.

The information set forth under Item 1.01 of this Current Report on Form 8-K is incorporated herein by reference.

The Notes were issued to the initial purchasers in reliance upon Section 4(a)(2) of the Securities Act, in transactions not involving any public offering. The 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 Notes will be issued in reliance upon Section 3(a)(9) of the Securities Act as involving an exchange by the Company exclusively with its security holders. Initially, a maximum of 5,893,200 shares of Common Stock may be issued upon conversion of the Notes, based on the maximum conversion rate of 3.9288 shares of Common Stock per $1,000 principal

amount of Notes, which is subject to customary anti-dilution adjustment provisions. Additional information pertaining to the Notes and the shares of Common Stock issuable upon conversion of the Notes is contained in Item 1.01 of this report and is incorporated herein by reference.

This Current Report on Form 8-K is neither an offer to sell, nor a solicitation of an offer to buy, any security and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offer, solicitation or sale would be unlawful.

Item 8.01

Other Events.

On May 18, 2026, the Company issued a press release announcing the pricing of the Notes. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated herein by reference.

Concurrently with the offering of the Notes, the Company used $204,979,372.25 of the net proceeds from the offering to repurchase 805,325 shares of Onto Innovation Inc.’s Common Stock in privately negotiated transactions effected with or through one of the initial purchasers or one or more of its affiliates, at a price per share equal to $254.53, the last reported sale price per share of Onto Innovation’s Common Stock on the New York Stock Exchange on May 18, 2026.

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, the Notes or the shares of Common Stock, if any, issuable upon conversion of the Notes.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits:


Exhibit No.		Description

4.1		Indenture, dated May 21, 2026, between Onto Innovation Inc. and the Trustee.

4.2		Form of Global Note representing Onto Innovation Inc.’s 0.00% Convertible Senior Notes due 2031 (included within Exhibit 4.1).

10.1		Form of Capped Call Confirmation.

99.1		Pricing Press Release dated May 18, 2026.

104		Cover Page Interactive Data File (formatted as inline XBRL and contained in the Inline XBRL document).

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.

Onto Innovation Inc. filed SEC Form 8-K: Entry into a Material Definitive Agreement