Final answer:
The Paramount Decision mandated the separation of production and exhibition in the Hollywood studio system.
Step-by-step explanation:
The Paramount Decision, handed down in 1948, mandated the separation of production and exhibition in the Hollywood studio system. This decision was made by the U.S. Supreme Court in the case of United States v. Paramount Pictures, Inc. The court ruled that the vertical integration of the film industry, where studios owned their own movie theater chains, was a violation of antitrust laws.