X0306 4 2016-10-19 0 0001679268 Mammoth Energy Services, Inc. TUSK 0001623083 Mammoth Energy Holdings LLC C/O WEXFORD CAPITAL LP 411 WEST PUTNAM AVE, SUITE 125 GREENWICH CT 06830 1 0 1 0 0001048462 WEXFORD CAPITAL LP 411 WEST PUTNAM AVENUE SUITE 125 GREENWICH CT 06830 1 0 1 0 0001472112 Wexford GP LLC C/O WEXFORD CAPITAL LP SUITE 125 GREENWICH CT 06830 1 0 1 0 0001001391 DAVIDSON CHARLES E C/O WEXFORD CAPITAL LP 411 WEST PUTNAM AVE. GREENWICH CT 06830 1 0 1 0 0001048485 JACOBS JOSEPH C/O WEXFORD CAPITAL LP 411 WEST PUTNAM AVENUE, SUITE 125 GREENWICH CT 06830 1 0 1 0 Restricted Stock Units(1) 6667 I see footnote Common Stock, par value $0.01 2016-10-19 4 S 0 171797 14.0625 D 20445923 D On October 19, 2015, the closing date (the "Closing Date") of the initial public offering of common stock, par value $0.01 per share (the "IPO"), of Mammoth Energy Services, Inc. (the "Issuer"), Wexford Capital LP ("Wexford"), on behalf of the services of Marc McCarthy ("McCarthy"), a director of the Issuer, was granted 6,667 restricted stock units ("RSU's") under the Issuer's 2016 Equity Incentive Plan (the "Plan"), subject to the terms and conditions set forth in the Plan. 2,223 RSU's vested on the Closing Date of the IPO, and the remaining 4,444 RSU's will vest in two equal annual installments beginning on October 19, 2017. Each RSU represents a contingent right to receive one share of common stock of the Issuer. McCarthy reported the acquisition of the RSU's on a Form 4 filed on the date hereof and indicated that these RSU's were assigned to Wexford under the terms of his employment with Wexford. These shares were sold to the underwriters in the IPO at a price of $14.0625 per share. The shares of common stock were received by MEH in connection with MEH's contribution of its membership interest in Mammoth Energy Partners LLC to the Issuer completed prior to the IPO, which contribution was approved by the board of directors of the Issuer in advance. This form is jointly filed by MEH, the owner of the common stock reported on this line, Wexford, Wexford GP LLC ("Wexford GP"), Charles E. Davidson ("Davidson") and Joseph M. Jacobs ("Jacobs"). The common stock shown as beneficially owned by Davidson, Jacobs, Wexford GP and Wexford, reflect the common stock that were owned of record by MEH. Wexford serves as manager for MEH and as such may be deemed to share beneficial ownership of the common stock beneficially owned by MEH, but disclaims such beneficial ownership to the extent such beneficial ownership exceeds its pecuniary interest. (*continued under Footnote (5) below). (*continued from Footnote (4) above) Wexford GP, as the general partner of Wexford, may be deemed to share beneficial ownership of the common stock beneficially owned by MEH, but disclaims such beneficial ownership to the extent such beneficial ownership exceeds its pecuniary interest. Messrs. Davidson and Jacobs, as the controlling persons of Wexford GP, may be deemed to share beneficial ownership of any common stock beneficially owned by MEH for which Wexford serves as manager, but disclaim such beneficial ownership to the extent such beneficial ownership exceeds their pecuniary interest. Wexford Capital LP, By: Wexford GP LLC, its general partner, By: Arthur Amron, Vice President and Assistant Secretary 2016-10-21 Wexford GP LLC By: Arthur Amron, Vice President and Assistant Secretary 2016-10-21 Mammoth Energy Holdings LLC, By: Arthur Amron, Vice President and Assistant Secretary 2016-10-21 Charles E. Davidson 2016-10-21 Joseph M. Jacobs 2016-10-21