Ralston Purina Loses Patent Case: A federal...

Ralston Purina Loses Patent Case: A federal judge in Peoria, Ill., has eliminated Ralston Purina Co.’s right to continue to enforce a patent used for the production of Purina Dog Chow. The judge ruled that in 1975, St. Louis-based Ralston Purina fraudulently obtained the patent for the process used to make soy protein, a prime ingredient of Purina Dog Chow. Ralston Purina said it plans to appeal.