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Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 FORM 10 - K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 or Delaware ( State or other jurisdiction of incorporation or organization ) 1615 Wynkoop Street Denver Colorado ( Address of principal executive offices ) Title of each class ANTERO MIDSTREAM CORPORATION ( Exact name of registrant as specified in its charter ) Commission File No. 001-38075 Antero Midstream Common Stock , par value $ 0.01 ( 303 ) 357-7310 ( Registrant's telephone number , including area code ) Securities registered pursuant to section 12 ( b ) of the Act : Trading Symbol ( s ) 61-1748605 ( IRS Employer Identification No. ) 80202 ( Zip Code ) Name of each exchange on which registered New York Stock Exchange AM Securities Registered Pursuant to Section 12 ( g ) of the Act : None . Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes 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 Indicate by check mark whether the registrant ( 1 ) has filed all reports required 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 ( §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 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 Emerging growth company Accelerated filer Smaller reporting company If an emerging growth company , indicate by checkmark if the registrant has elected 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 . □ Non - accelerated filer 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 . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Exchange Act ) . Yes > No The aggregate market value of the voting common stock held by non - affiliates of the registrant as of June 30 , 2020 , the last business day of the registrant's most recently completed second fiscal quarter , was approximately $ 1.6 billion based on the $ 5.10 per share closing price of Antero Midstream Corporation's common stock as reported on that day on the New York Stock Exchange . The registrant had 476,906,973 shares of common stock outstanding as of February 12 , 2021 . Documents incorporated by reference : Portions of the registrant's proxy statement for its annual meeting of stockholders to be filed pursuant to Regulation 14A within 120 days after the registrant's fiscal year end are incorporated by reference into Part III of this Annual Report on Form 10 - K .