The United States v. Continental Can Co. case in 1963 was a significant antitrust lawsuit where the U.S government accused Continental Can Company of violating Section 7 of the Clayton Act, which prohibits mergers and acquisitions that may substantially lessen competition or create a monopoly. The company had acquired Hazel-Atlas Glass Company, another major player in the glass container industry, thereby significantly increasing its market share and reducing competition. The Supreme Court ruled against Continental Can Co., stating that even though there were still other competitors left in the market after this acquisition, it did not negate the fact that this merger would likely reduce competition overall by creating an environment conducive to price coordination among remaining firms. This ruling expanded interpretations of Section 7 to include potential as well as actual harm to competition due to mergers and acquisitions.

The dissenting opinion in the United States v. Continental Can Co. case argued that the majority's decision was too broad and could potentially stifle legitimate business growth and competition. The dissenters believed that while antitrust laws are important for preventing monopolies, they should not be used to prevent a company from acquiring another if it does not significantly reduce competition or create a monopoly. They pointed out that there were still numerous competitors in the market even after Continental Can's acquisition of Hazel-Atlas Glass Company, suggesting that this merger did not result in an unfair advantage or harm consumer interests as alleged by the government’s prosecution team.