Page 1

( Mark One ) X ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31 , 2020 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON D.C. 20549 FORM 10 - K Delaware ( State or Other Jurisdiction of Incorporation or Organization ) COMMISSION FILE NUMBER 1-13455 24955 Interstate 45 North ( Address of Principal Executive Offices ) TETRA Technologies , Inc. ( Exact name of registrant as specified in its charter ) Securities registered pursuant to Section 12 ( b ) of the Act : Title of each class Common Stock TO Large accelerated filer Non - accelerated filer ロロ The Woodlands , ( 281 ) 367-1983 ( Registrant's Telephone Number , Including Area Code ) Trading Symbol ( s ) TTI Texas Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes No X 74-2148293 ( I.R.S. Employer Identification No. ) 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 No X Name of each exchange on which registered New York Stock Exchange 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 Accelerated filer Smaller reporting company Emerging growth company 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 ( §232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes X No 77380 ( Zip Code ) 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 . ☐ × × 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 . The aggregate market value of common stock held by non - affiliates of the Registrant was $ 64,937,973 as of June 30 , 2020 . As of March 3 , 2021 , TETRA Technologies , Inc. had 126,635,900 shares outstanding . DOCUMENTS INCORPORATED BY REFERENCE 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 . Yes No Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes No Part III information is incorporated by reference to the registrant's proxy statement for its annual meeting of stockholders to be held April 29 , 2021 , to be filed with the Securities and Exchange Commission within 120 days of the end of the registrant's fiscal year .