X0306 4 2018-07-30 0001679268 MAMMOTH ENERGY SERVICES, INC. TUSK 0001710079 MEH SUB LLC C/O WEXFORD CAPITAL LP 777 SOUTH FLAGLER DRIVE, SUITE 602 EAST WEST PALM BEACH FL 33401 true true 0001048462 WEXFORD CAPITAL LP 777 SOUTH FLAGLER DRIVE, SUITE 602 EAST WEST PALM BEACH FL 33401 true true 0001472112 Wexford GP LLC C/O WEXFORD CAPITAL LP 777 SOUTH FLAGLER DRIVE, SUITE 602 EAST WEST PALM BEACH FL 44302 true true 0001001391 DAVIDSON CHARLES E C/O WEXFORD CAPITAL LP 777 SOUTH FLAGLER DRIVE, SUITE 602 EAST WEST PALM BEACH FL 33401 true true 0001048485 JACOBS JOSEPH C/O WEXFORD CAPITAL LP 777 SOUTH FLAGLER DRIVE, SUITE 602 EAST WEST PALM BEACH FL 33401 true true Restricted Stock Units 12235 I See Footnote Common Stock 2018-07-30 4 S 0 266026 38.01 D 21978893 D Marc McCarthy ("McCarthy"), a director of Mammoth Energy Services, Inc. (the "Issuer") and an employee of Wexford Capital LP ("Wexford Capital"), was granted an aggregate of 12,235 restricted stock units ("RSUs") under the Issuer's 2016 Equity Incentive Plan, subject to terms and conditions set forth in the Plan. 6,667 RSUs were granted on October 19, 2016, as reported on the Form 4 filed with the U.S. Securities and Exchange Commission (the "SEC") on October 21, 2016, 2,913 RSUs were granted on February 2, 2018, as reported on the Form 4 filed with the SEC on February 6, 2018, and 2,655 RSUs were granted on June 7, 2018, as reported on the Form 4 filed with the SEC on June 11, 2018. Vesting schedules for these RSUs are set forth in each respective Form 4. The RSUs were assigned to Wexford Capital under the terms of McCarthy's employment with Wexford. The Reporting Persons are directors by deputization because McCarthy serves as a director of the Issuer. Each RSU represents a contingent right to receive one share of common stock of the Issuer. These shares of common stock of the Issuer were sold by MEH SUB LLC ("MEH") to the underwriters in a secondary public offering of the common stock at a price of $38.01 per share, in connection with the underwriters' partial exercise of their option to purchase additional shares of the Issuer's common stock from MEH and the other selling stockholder granted by such selling stockholders in the previously reported June 2018 secondary offering (the "Option Exercise"). The Option Exercise closed on July 30, 2018. Other material terms of the Offering are described in the Form 424B5, dated June 19, 2018, filed by the Issuer with the SEC on June 28, 2018. Wexford Capital may, by reason of its status as manager of MEH, be deemed to own beneficially the securities of which MEH possesses beneficial ownership. Wexford GP LLC ("Wexford GP") may, as the General Partner of Wexford Capital, be deemed to own beneficially the securities of which MEH possesses beneficial ownership. Each of Charles E. Davidson ("Davidson") and Joseph M. Jacobs ("Jacobs") may, by reason of his status as a controlling person of Wexford GP, be deemed to own beneficially the securities of which MEH possesses beneficial ownership. Each of Wexford Capital, Wexford GP, Davidson and Jacobs share the power to vote and to dispose of the securities beneficially owned by MEH. Each of Wexford Capital, Wexford GP, Davidson and Jacobs disclaim beneficial ownership of the securities owned by MEH and this report shall not be deemed as an admission that they are the beneficial owners of such securities, except to the extent of any pecuniary interests therein. MEH SUB LLC, By: Arthur Amron, Vice President and Assistant Secretary 2018-08-01 Wexford Capital LP, By: Wexford GP LLC, its general partner, By: Arthur Amron, Vice President and Assistant Secretary 2018-08-01 Wexford GP LLC, By: Arthur Amron, Vice President and Assistant Secretary 2018-08-01 Charles E. Davidson 2018-08-01 Joseph M. Jacobs 2018-08-01