Masson Scott Thrissell Engineering Limited was formed in 1963 following the acquisition of Thrissell Engineering Company by Masson Scott & Company Limited. Thrissell Engineering Company had been a subsidiary of Molins Machine Company, and this parent company became the majority shareholder in the newly established Masson Scott Thrissell Engineering Limited. The company was based in London, but planned to open a factory in South Wales in 1970. Instead a site at Bristol was developed, and this expanded in 1972 following the closure of the company’s sites in Hayes, Middlesex and Wimbledon, London. In 1973, Molins Machine Company increased its shareholding in Masson Scott Thrissell Engineering Limited to 97%. The company was restructured in 1982.