''Knauf Gips KG'' is a multinational, family-owned company based in Iphofen, Germany, well known for drywall gypsum boards, founded in 1932. The company is a producer of building materials and construction systems comprising construction materials for drywall construction, plasterboard, cement boards, mineral fibre acoustic boards, dry mortars with gypsum for internal plaster and cement-based external plaster and insulating materials; glass wool, stone wool and other insulation materials under the company Knauf Insulation. It has more than 150 production sites worldwide. It is one of the seven producers which hold approximately 81% of the worldwide wallboard market (Georgia Pacific, Knauf, Siniat, National Gypsum Company, Saint-Gobain, and Yoshino Gypsum Co., Ltd).