Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock, par value $0.01 per share^{F1,F2,F3,F5,F6}	Mar 16, 2017	S	2,484,078	$21.06	D	4,616,197	I	See Footnotes
Common Stock, par value $0.01 per share^{F1,F2,F4,F5,F6}	Mar 16, 2017	S	115,922	$21.06	D	215,420	I	See Footnotes

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1Represents shares of BMC Stock Holdings, Inc.'s (the "Issuer") common stock sold in an underwritten secondary offering.
F2Represents the offering price to the underwriters in the secondary offering of $21.06 per share.
F3These shares are held of record by Gores Building Holdings, LLC ("Gores Holdings").
F4These shares are held of record by Glendon Saturn Holdings, LLC ("Glendon Saturn").
F5The Gores Group, LLC ("Gores") is the manager of Gores Holdings and Glendon Saturn and Alec E. Gores is the manager of Gores. Gores Capital Partners II, L.P. ("Gores II") is the controlling member of Gores Holdings. Gores Capital Advisors II, LLC ("Gores Advisors") is the general partner of Gores II. Gores is the manager of Gores Advisors. Gores has a five member investment committee that has voting and dispositive authority over the common stock held of record by Gores Holdings and Glendon Saturn.
F6(continued from Footnote 5) The members of the investment committee include Alec E. Gores, Mark R. Stone, Vance W. Diggins, Fernando Goni and Steven C. Yager. Each of the foregoing persons may be deemed to share voting and dispositive power with respect to the shares he1d of record by Gores Holdings and Glendon Saturn. None of the members of the investment committee, acting alone, has voting or dispositive power over any shares. Each of the reporting persons disclaims beneficial ownership of the shares except to the extent of such person's pecuniary interest therein.