In the United States v. Parke, Davis & Co., 1960 case, pharmaceutical manufacturer Parke, Davis & Company was accused of violating antitrust laws by coercing wholesalers and retailers to not sell or advertise its products below a certain price. The company argued that it merely suggested prices and did not enforce them. However, the Supreme Court ruled against Parke, Davis & Co., stating that even though no formal agreement on price-fixing existed between the company and its distributors/retailers, their conduct amounted to an illegal combination for fixing prices under Section 1 of Sherman Act (an anti-monopoly law). This decision expanded upon previous rulings regarding vertical price agreements in U.S. antitrust law.

The dissenting opinion in the United States v. Parke, Davis & Co. case argued that the majority's decision to find Parke, Davis & Co guilty of violating antitrust laws was incorrect because it did not take into account the nature of competition within a free market economy. The dissenters believed that there was no evidence showing that Parke, Davis & Co had coerced its competitors into maintaining fixed prices or used predatory tactics to eliminate competition. They also pointed out that price fixing is only illegal if it restricts trade and harms consumers, which they claimed wasn't proven in this case. Furthermore, they contended that manufacturers should have some control over their product’s resale price as long as such practices do not result in monopolistic control or harm consumer welfare.