X0306 4 2019-03-12 0 0001623925 Antero Midstream Corp AM 0001423201 Yorktown VII Associates LLC 410 PARK AVENUE, 19TH FLOOR NEW YORK NY 10022 1 0 1 0 Common shares representing limited partner interests 2019-03-12 4 D 0 4596064 D 0 I See Footnotes Common Stock 2019-03-12 4 D 0 4596064 A 4596064 I See Footnotes On March 12, 2019, in connection with the conversion of Antero Midstream GP LP ("AMGP") from a limited partnership to a corporation named Antero Midstream Corporation ("New AM") under the laws of the State of Delaware, each common share representing limited partnership interests of AMGP was converted into one share of common stock of New AM. These securities are owned directly by Yorktown Energy Partners VII, L.P. ("Yorktown VII"). The Reporting Person is the sole general partner of Yorktown VII Company LP. Yorktown VII Company LP is the sole general partner of Yorktown VII. The Reporting Person disclaims beneficial ownership of these securities except to the extent of its pecuniary interest therein and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the securities for Section 16 or any other purpose. Yorktown VII is a director-by-deputization solely for purposes of Section 16 of the Exchange Act. Yorktown VII Associates LLC /s/ W. Howard Keenan, Jr., Manager 2019-03-14