In the case of Pan American World Airways, Inc. v. United States in 1962, the U.S Supreme Court ruled that Pan American World Airways (Pan Am) had violated antitrust laws by acquiring a controlling interest in its competitor, Grace Line Inc., through an exchange of stock. The government argued that this acquisition would reduce competition and create a monopoly for international air travel between certain points in South America and New York City. Despite arguments from Pan Am suggesting their actions were permissible under exceptions to antitrust law for regulated industries such as airlines, the court disagreed with them stating these exceptions did not apply when there was potential harm to competition or consumers. As a result of this ruling, Pan Am was ordered to divest itself of its holdings in Grace Line.

In the dissenting opinion for Pan American World Airways, Inc., v. United States (1962), it was argued that the majority's decision to uphold a Civil Aeronautics Board order requiring Pan Am to cease and desist from certain practices related to its overseas air transportation services was incorrect. The dissenting justices believed that this case should have been decided based on antitrust laws rather than regulatory statutes governing aviation. They contended that the CAB had overstepped its authority by regulating areas of competition not explicitly covered in their mandate, such as pricing and market entry or exit decisions made by airlines. Furthermore, they disagreed with the majority's interpretation of "public convenience and necessity," arguing instead that these terms should be interpreted more narrowly in line with traditional economic principles of supply and demand.