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Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON , D.C. 20549 ( Mark One ) ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Fiscal Year Ended December 26 , 2020 OR FORM 10 - K TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File No. 001-39110 ONTO INNOVATION INC . ( Exact name of registrant as specified in its charter ) Delaware ( State or other jurisdiction of incorporation or organization ) 94-2276314 ( I.R.S. Employer Identification Number ) 16 Jonspin Road , Wilmington , MA 01887 ( Address of principal executive offices ) ( Zip Code ) Registrant's telephone number , including area code : ( 978 ) 253-6200 Title of Each Class Common Stock , $ 0.001 par value per share SECURITIES REGISTERED PURSUANT TO SECTION 12 ( b ) OF THE ACT : Trading Symbol ΟΝΤΟ Name of Exchange on Which Registered New York Stock Exchange ( NYSE ) SECURITIES REGISTERED PURSUANT TO SECTION 12 ( g ) OF THE ACT : None No No | Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes > Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Act . Yes Indicate by check mark whether the registrant : ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes No Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes > NO □ Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company " and " emerging growth company " in Rule 12b - 2 of the Exchange Act .: Large accelerated filer Non - accelerated filer Accelerated filer Smaller reporting company 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 . □ Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . No 冈 Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes The aggregate market value of the registrant's voting Common Stock held by non - affiliates of the registrant was approximately $ 1,568,582,829 based on the closing price of the Common Stock on the New York Stock Exchange on June 26 , 2020 . The number of shares of the registrant's Common Stock outstanding as of February 4 , 2021 was 48,883,050 . DOCUMENTS INCORPORATED BY REFERENCE Items 10 , 11 , 12 , 13 and 14 of Part III of this Annual Report on Form 10 - K incorporate by reference information from the definitive proxy statement for the registrant's annual meeting of stockholders scheduled to be held on May 11 , 2021 .