On January 1, 2021, Builders FirstSource, Inc. completed its previously announced all stock merger transaction with BMC Stock Holdings, Inc., pursuant to the Agreement and Plan of Merger, dated as of August 26, 2020 (as amended, restated, supplemented, or otherwise modified from time to time, the Merger Agreement"), by and among Builders FirstSource, Boston Merger Sub I Inc., a Delaware corporation and a direct wholly owned subsidiary of Builders FirstSource (Merger Sub), and BMC. On the terms and subject to the conditions set out in the Merger Agreement, at the effective time of the Merger on January 1, 2021 (the Effective Time), Merger Sub merged with and into BMC, with BMC continuing as the surviving corporation and a wholly owned subsidiary of Builders FirstSource (the Merger). As contemplated by the Merger Agreement, at the Effective Time, the size of the Board of Directors of Builders FirstSource (the Board") was increased to consist of twelve directors. Each of David A. Barr, M. Chad Crow, and Janice L. Davis resigned from the Board and from all committees of the Board of which such individual was a member, effective as of immediately prior to the Effective Time, but conditioned on, and subject to, consummation of the Merger. Effective as of the Effective Time, the Board consists of twelve directors: (i) seven directors designated by Builders FirstSource (the BLDR Designees"), and (ii) five directors designated by BMC (the BMC Designees"). The BLDR Designees are Paul S. Levy, who will serve as Chairman of the Board, Daniel Agroskin, Cleveland A. Christophe, W. Bradley Hayes, Brett N. Milgrim, Floyd F. Sherman, and Craig A. Steinke. The BMC Designees are David E. Flitman, Mark Alexander, Cory J. Boydston, David W. Bullock, and James O'Leary. The members of the Board have been appointed to the following classes, as of the Effective Time: Cleveland A. Christophe, David E. Flitman, W. Bradley Hayes, and Brett N. Milgrim serve in Class I of the Board; Daniel Agroskin, Mark Alexander, David W. Bullock, and Floyd F. Sherman serve in Class II of the Board; and Paul S. Levy, Cory J. Boydston, James O'Leary, and Craig A. Steinke serve in Class III of the Board. The composition of the standing committees of the Board, as of the Effective Time, are as follows: (i) the Audit Committee of the Board consists of Mark Alexander, Cory J. Boydston, W. Bradley Hayes, and Craig A. Steinke, with W. Bradley Hayes as the chairman of the committee; (ii) the Nominating and Corporate Governance Committee of the Board consists of David W. Bullock, Cleveland A. Christophe, and Craig A. Steinke, with Craig A. Steinke as the chairman of the committee; and (iii) the Compensation Committee of the Board consists of Daniel Agroskin, Cleveland A. Christophe, Brett N. Milgrim, and James O'Leary, with Cleveland A. Christophe as the chairman of the committee. In connection with the Merger and effective at the Effective Time, Mr. M. Chad Crow, the current Chief Executive Officer of Builders FirstSource, ceased to serve as President of Builders FirstSource, and, pursuant to the previously disclosed Flitman Employment Agreement, Mr. David E. Flitman was appointed President of Builders FirstSource. Effective on the ninety-first (91st) day following the Effective Time and following the retirement of Mr. Crow as Chief Executive Officer of Builders FirstSource, Mr. Flitman will also be appointed to serve as the Chief Executive Officer of Builders FirstSource. In connection with the Merger and effective prior to the Effective Time, as previously announced, Mr. Donald F. McAleenan resigned as Senior Vice President, General Counsel, and Secretary of Builders FirstSource. Mr. McAleenan remains an employee of Builders FirstSource. In connection with the Merger and effective at the Effective Time, Mr. David E. Rush, the current Senior Vice President & Chief Operating Officer East of Builders FirstSource, was elected by the Board to serve as the Executive Vice President Integration of Builder FirstSource and will cease to serve as Senior Vice President & Chief Operating Officer East. In connection with the Merger and effective at the Effective Time, Mr. Scott Robins, the current Senior Vice President & Chief Operating Officer West of Builders FirstSource, was elected by the Board to serve as the President West Division of Builder FirstSource and will cease to serve as Senior Vice President & Chief Operating Officer West. In connection with the Merger and effective at the Effective Time, Mr. Peter Jackson, the current Senior Vice President and Chief Financial Officer of Builders FirstSource, was elected by the Board to serve as the Executive Vice President and Chief Financial Officer of Builder FirstSource.