In the United States v. Hilton Hotels Corp., 1969, the U.S Supreme Court ruled in favor of the government, upholding a lower court's decision that Hilton Hotels Corporation had violated antitrust laws by acquiring two hotels in Chicago and Los Angeles through stock purchases. The case centered on whether these acquisitions constituted a violation of Section 7 of the Clayton Act, which prohibits mergers or acquisitions that may substantially lessen competition or tend to create a monopoly. The Court held that even though there was no immediate effect on competition due to existing competitive conditions at both locations, potential future effects were enough for an infringement finding under Section 7. Therefore, it concluded that any acquisition violating this provision is illegal regardless if its impact on competition is not immediately apparent but could potentially be harmful in the future.

The dissenting opinion in the United States v. Hilton Hotels Corp. case argued that the majority's decision was based on a misinterpretation of Section 1 of the Sherman Act, which prohibits any contract or conspiracy to restrain trade or commerce among several states. The dissenters believed that there was no evidence showing an agreement between Hilton and other hotels to fix prices for hotel rooms, which would constitute such a restraint on trade. They also disagreed with the majority's view that price parallelism alone could be enough to infer collusion among competitors, arguing instead that this behavior might simply reflect independent responses to similar market conditions rather than an illegal conspiracy. Furthermore, they contended that even if there had been some form of cooperation between different hotels regarding pricing policies, it did not necessarily mean these practices were anticompetitive or harmful to consumers.