Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock, $0.001 par value^{F1,F2,F3,F4,F5,F6}	May 23, 2017	P	514,227	$1.2289	A	56,712,088	I	See footnotes
Common Stock, $0.001 par value^F7	holding	—	—		—	52,910	I	See footnote

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1The amount reported reflects an aggregate 514,227 shares of the Issuer's common stock, par value $0.001 ("Common Stock") acquired in the following individual amounts: 25,548 shares by AF V Energy I AIV A1, L.P., 25,318 shares by AF V Energy I AIV A2, L.P., 25,348 shares by AF V Energy I AIV A3, L.P., 25,482 shares by AF V Energy I AIV A4, L.P., 25,613 shares by AF V Energy I AIV A5, L.P., 25,453 shares by AF V Energy I AIV A6, L.P., 24,892 shares by AF V Energy I AIV A7, L.P., 25,220 shares by AF V Energy I AIV A8, L.P., 25,548 shares by AF V Energy I AIV A9, L.P., 25,548 shares by AF V Energy I AIV A10, L.P., 25,220 shares by AF V Energy I AIV A11, L.P., 24,892 shares by AF V Energy I AIV A12, L.P., 30,002 shares by AF V Energy I AIV A13, L.P., and 180,143 shares by AF V Energy I AIV B1, L.P.
F2The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $1.20 to $1.26, inclusive. The undersigned undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.
F3The manager of the entities (collectively, the "Purchasers") identified in footnotes (1) and (6) is ACOF Investment Management LLC ("ACOF"). The sole member of ACOF is Ares Management LLC, and the sole member of Ares Management LLC is Ares Management Holdings L.P. ("Ares Management Holdings") and the general partner of Ares Management Holdings is Ares Holdco LLC ("Ares Holdco"). The sole member of Ares Holdco is Ares Holdings Inc. ("Ares Holdings"), whose sole stockholder is Ares Management, L.P. ("Ares Management").
F4The general partner of Ares Management is Ares Management GP LLC ("Ares Management GP") and the sole member of Ares Management GP is Ares Partners Holdco LLC ("Ares Partners," and together with the Purchasers, ACOF, Ares Management LLC, Ares Management Holdings, Ares Holdco, Ares Holdings, Ares Management, and Ares Management GP, the "Ares Entities"). Ares Partners is managed by a board of managers, which is composed of Michael Arougheti, R. Kipp deVeer, David Kaplan, Antony Ressler and Bennett Rosenthal. (continued in footnote 5)
F5Decisions by Ares Partners' board of managers generally are made by a majority of the members, which majority, subject to certain conditions, must include Antony Ressler. Each of the Ares Entities (other than each Purchaser, with respect to the securities held directly by it) and the members of Ares Partners' board of managers and the other directors, officers, partners, stockholders, members and managers of the Ares Entities expressly disclaims beneficial ownership of the securities reported on this Form 4, except to the extent of any pecuniary interest therein, and this Form 4 shall not be deemed an admission that any such person or entity is the beneficial owner of, or has any pecuniary interest in, such securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purposes. The address of each Ares Entity is 2000 Avenue of the Stars, 12th Floor, Los Angeles, CA 90067.
F6The amount reported reflects an aggregate 56,712,088 shares of Common Stock held in the following individual amounts: 2,817,506 shares by AF V Energy I AIV A1, L.P., 2,792,028 shares by AF V Energy I AIV A2, L.P., 2,795,856 shares by AF V Energy I AIV A3, L.P., 2,810,129 shares by AF V Energy I AIV A4, L.P., 2,824,880 shares by AF V Energy I AIV A5, L.P., 2,806,979 shares by AF V Energy I AIV A6, L.P., 2,745,103 shares by AF V Energy I AIV A7, L.P., 2,781,304 shares by AF V Energy I AIV A8, L.P., 2,817,506 shares by AF V Energy I AIV A9, L.P., 2,817,506 shares by AF V Energy I AIV A10, L.P., 2,781,304 shares by AF V Energy I AIV A11, L.P., 2,745,781 shares by AF V Energy I AIV A12, L.P., 3,308,876 shares by AF V Energy I AIV A13, L.P., and 19,867,330 shares by AF V Energy I AIV B1, L.P.
F7The amount reported reflects 52,910 shares held by Nathan Walton, which represents shares granted to Mr. Walton in his capacity as a director of the Issuer. Mr. Walton is associated with Ares Management LLC and certain of the other Ares Entities (as defined above). Pursuant to the policies of the Ares Entities, Mr. Walton holds these securities as a nominee on behalf of, and for the sole benefit of, the Ares Entities and has assigned to Ares Management LLC all economic, pecuniary and voting rights in respect of such securities.

Remarks

Ares Management LLC and its affiliates designated two individuals who were appointed to the board of directors of the Issuer on May 2, 2017. Accordingly, Ares Management LLC and its affiliates listed hereon may be deemed to be a director by deputization.