In 1902 Sheffield steelmakers John Brown and Company exchanged shares and worked with neighbouring company Thomas Firth & Sons. The companies continued under their own management until they merged in 1930 becoming Firth Brown Steels. In 1998 the company was sold in two sections to American buyers, the aerospace section was sold to Allegheny Teledyne and the River Don and Rolls section to Atchison Castings.