Cardinal IG Company is a subsidiary of Cardinal Glass Industries. Cardinal Glass Industries is a management-owned S-corporation that provides window and door glass to the residential market. The company operates through three wholly owned subsidiaries, including Cardinal IG Company, which offers insulating and laminated glass; Cardinal CG Company, which provides coated glass and optical mirrors; and Cardinal FG Company, which specializes in float and tempered glass. The company employs more than 6,500 employees and operates 25-plus manufacturing locations throughout the United States. It also has research and development centers in Minnesota and Wisconsin. Cardinal IG Company operates a plant in Greenfield, Iowa.