In 1930 O. Zimmerman founded the company Technical Bureau for cast iron products Soest (Technisch Bureau voor gietijzer producten Soest) in the city of Soest. Over the years, the company has moved to other places, and has grown in size. If in 1950 the company had 21 employees, then in the 1980s it had 140 employees. In 1990 the company became part of Ballast Nedam. In 2017 the company was acquired by the investment company Triacta and in 2020 it is part of the TBS-SVA Group