The major film studios owned the theaters where their motion pictures were shown, either in partnerships or outright and complete. Thus specific theater chains showed only the films produced by the studio that owned them. The studios created the films, had the writers, directors, producers and actors on staff ("under contract" as it was called), owned the film processing and laboratories, created the prints and distributed them through the theaters that they owned: In other words, the studios were [[vertical integration|vertically integrated]], creating a de facto [[oligopoly]]. By 1945, the studios owned either partially or outright 17% of the theaters in the country, accounting for 45% of the film-rental revenue.[[William O. Douglas]], ''United States v. Paramount Pictures Inc.