 C. F. Theodor Steinweg obeyed, selling his share of the German piano company to his partner, Wilhelm Grotrian (son of Friedrich Grotrian), and two other workmen, Adolph Helfferich and H.G.W.Schulz.The German factory changed its name from "C. F. Theodor Steinweg" to "Grotrian, Helfferich, Schulz, Th.