In 1905 Michael P. Grace--a brother of William R. Grace, who founded W.R. Grace & Company--brought Ingersoll-Sergeant Drill Company and the Rand Drill Company together. The two companies had specialized in slightly different segments of the drill market--Ingersoll-Sergeant specialized in construction work while Rand focused on underground mining--and their interests were complementary. The new company was incorporated as the Ingersoll-Rand Company (IR) in June 1905 and billed itself as "the largest builder of air power machinery in the world." The Grace family owned the largest single block of stock, and a Grace has served on the IR board ever since.