In the early 20th century, Hollywood operated under a 'Vertical Integration' model. Major studios like Paramount, MGM, and Warner Bros. owned not only the production lots and the actors' contracts but also the theaters themselves. This allowed them to engage in 'block booking,' forcing independent theaters to buy a year's worth of mediocre films just to get one hit movie. In 1948, the Supreme Court case 'United States v. Paramount Pictures, Inc.' (the Paramount Decree) ruled this a violation of antitrust laws. Studios were forced to sell off their theater chains. This landmark ruling ended the 'Studio System,' gave rise to independent production companies, and allowed foreign and independent films to finally compete for screen time in American theaters, fundamentally democratizing the film industry.