 All other countries, among them Italy, France, and England, are open to both parties.The agreement did not resolve all the patent disputes, and further negotiations were undertaken and concords signed over the course of the 1930s.During these years, as well, the American studios began abandoning the Western Electric system for RCA Photophone's variable-area approach—by the end of 1936, only Paramount, MGM, and United Artists still had contracts with ERPI.