Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock, $0.10 par value^F1,F2,F3,F4	May 11, 2016	P	140,000	$16.4015	A	503,618	I	See footnotes
Common Stock, $0.10 par value^F5,F2,F3,F4	May 12, 2016	P	208,600	$17.813	A	712,218	I	See footnotes
Common Stock, $0.10 par value^F6,F2,F3,F4	May 13, 2016	P	166,805	$19.4181	A	879,023	I	See footnotes

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $15.3800 to $17.5000, 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 footnotes (1), (5) and (6) to this Form 4.
F2The amounts of securities acquired reported in this Form 4 reflect an aggregate of 515,405 shares purchased in open market purchases, in the following amounts: 49,773 shares by AF IV Energy AIV A1, L.P., 9,097 shares by AF IV Energy AIV A2, L.P., 55,378 shares by AF IV Energy AIV A3, L.P., 54,283 shares by AF IV Energy AIV A4, L.P., 54,474 shares by AF IV Energy AIV A5, L.P., 55,378 shares by AF IV Energy AIV A6, L.P., 27,415 shares by AF IV Energy AIV A7, L.P. and 209,607 shares by AF IV Energy AIV B1, L.P. The manager of the foregoing entities is Ares Management LLC. (continued in footnote 3)
F3The 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"). The 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 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, David Kaplan, John Kissick, Antony Ressler and Bennett Rosenthal. (Continued in footnote 4)
F4Decisions 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 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 these securities, 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.
F5The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $17.3400 to $18.3700, inclusive.
F6The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $18.3000 to $19.9800, inclusive.

Remarks

Affiliates of Ares Management LLC and the Ares Entities hold all of the shares of a series of special voting preferred stock of the Issuer. The shares of the special voting preferred stock grant the holders thereof the right to elect up to two members of the board of directors of the Issuer, subject to reduction based on the warrants held by such holders, their respective affiliates and other permitted transferees that remain unexercised in respect of a specified number of shares for which such warrants are exercisable. The holders of the series of special voting preferred stock elected two members to the board of directors of the Issuer on March 31, 2016 and accordingly, Ares Management LLC and the Ares Entities may be deemed to be a director by deputization.