In the 1955 case American Airlines, Inc. v. North American Airlines, Inc., et al., the U.S Supreme Court dealt with a dispute over trademark infringement and unfair competition. The plaintiff, American Airlines (AA), argued that North American Airline's name was so similar to its own that it could cause confusion among consumers and harm AA's business reputation. The court agreed with AA’s argument stating that even though there were no instances of actual confusion demonstrated by AA, potential for confusion existed due to similarity in names and areas of operation between two airlines which is enough for an injunction under federal law against unfair competition. Thus, the court ruled in favor of American Airlines.

In the dissenting opinion for the case of American Airlines, Inc. v. North American Airlines, Inc., et al., it was argued that the majority's decision to uphold an injunction against North American Airlines' use of "American" in its name and advertising materials was overly broad and potentially harmful to competition within the airline industry. The dissenting justices believed that while there may have been some potential for confusion among consumers due to similarities between company names, this did not justify such a sweeping restriction on North American's ability to conduct business under its chosen name. They also expressed concern about setting a precedent where larger companies could effectively monopolize common words or phrases simply by incorporating them into their brand identities first.