The SIMPP v. UDTC Collection spans the years 1930-1952 (bulk 1947-1952) and encompasses 1.0 linear foot. The collection consists primarily of case proceedings, including the plaintiff's complaint and hearing transcript, court documents from similar past cases, and depositions of Hunt Stromberg, David O. Selznick, and others. Other material of interest includes theater booking contracts and 1940s interviews with exhibitors. A 1947 letter reporting on the resolutions passed at a series of MPAA-sponsored meetings regarding HUAC and the Hollywood Ten is of interest.

The Society of Independent Motion Picture Producers, Inc. (SIMPP), was formed in 1942 to strengthen and protect the role and function of the independent producer, to adhere to sound artistic and economic practices, and to promote the wise use of the medium of motion pictures. The eight charter members included Charles Chaplin, Walt Disney, Samuel Goldwyn, Alexander Korda, Mary Pickford, David O. Selznick, Walter Wanger, and Orson Welles. Later members included William Cagney, Sol Lesser, and Hal Roach. The first president was attorney Loyd Wright, followed by former War Production Board chief Donald M. Nelson and former Georgia governor Ellis Arnall. The group was supported by a fractional percentage of the gross of its members' product. SIMPP fought to end monopolistic practices by the five major film studios, who controlled the production, distribution, and exhibition of films. To that end, the SIMPP suit against United Detroit Theatres Corporation, Inc. (UDTC), was filed in the U.S. District Court, Eastern District of Michigan, in 1948. It was the first antitrust suit brought by producers against exhibitors alleging monopoly and restraint of trade. The complaint accused two Detroit circuits of maintaining a conspiracy to control first-run and subsequent-run theaters in Detroit and its environs. Apparently the case never went to trial. SIMPP curtailed its activities in 1958, citing falling revenues and changed conditions in Hollywood (as a result of the consent decree). The Los Angeles office closed in August 1958.