Tranche Update on USG Corporation's Equity Buyback Plan announced on February 1, 2017.

USG Corporation, through its subsidiaries, is a manufacturer and distributor of building materials. The Company's segments include Gypsum, Ceilings and USG Boral Building Products (UBBP). It produces a range of products for use in new residential, new nonresidential, and residential and nonresidential repair and remodel construction, as well as products used in certain industrial processes. Its products are distributed through building materials dealers, home improvement centers and other retailers, specialty wallboard distributors, and contractors. Gypsum segment manufactures and markets gypsum and related products in the United States, Canada, Mexico and Latin America. Ceilings segment manufactures and markets interior systems products in the United States, Canada, Mexico and Latin America. The UBBP segment manufactures, distributes and sells certain building products, mines raw gypsum and sells natural and synthetic gypsum throughout Asia, Australasia and the Middle East.