After a four-month investigation resulted in the Department of Justice filing a civil antitrust lawsuit against the five parties to block the Showtime-TMC merger on June 10, 1983, the Department asked Warner and American Express to restructure the deal during hearings for the case. The Department's decision – citing concerns, including some expressed by HBO management, that combining the assets of Showtime and TMC would stifle competition in the sale of their programming and that of other pay cable services to cable providers – was despite the fact that, under the original proposal, MCA, Gulf+Western and Warner had each agreed to continue licensing films released by their respective movie studios to competing pay television networks. The partners involved in the merger would also set standard prices for films that were acquired for broadcast on The Movie Channel and Showtime, either those produced by the studio partners or by unassociated film studios. To address the Justice Department's concerns over the deal, the four partners submitted another revised proposal for consideration on July 19, that included guarantees of conduct agreeing that Paramount, Universal and Warner Bros. would not receive higher residual licensing payments for films acquired by Showtime and The Movie Channel than that paid by other studios, and that all four partners would not permit the two channels in the venture to pay lower fees for films produced by three studio partners than that paid by smaller pay television services for the same films.