The United States v. E.C. Knight Company case in 1894 was a landmark decision by the Supreme Court that significantly limited the government's power to control monopolies under the Sherman Antitrust Act of 1890. The federal government sued E.C. Knight Company, which controlled about 98% of sugar refining industry, arguing it was a monopoly and violated antitrust laws designed to promote competition and limit market domination by single entities. However, the Supreme Court ruled in favor of E.C Knight Co., stating that manufacturing is not considered commerce; thus, it falls outside federal jurisdiction for regulation under interstate commerce clause as per constitution's interpretation at that time. This ruling effectively narrowed down Congress' ability to regulate industrial activities leading to creation or operation of monopolies until later court decisions expanded its scope again.

The dissenting opinion in the United States v. E.C. Knight Company case argued that the majority's interpretation of the Sherman Anti-Trust Act was too narrow and failed to address its intended purpose: to prevent monopolies from controlling commerce among states. The dissenters believed that manufacturing, which directly impacts interstate commerce, should be considered within Congress' regulatory power under the Commerce Clause of Constitution. They contended that by allowing a sugar refining company to control about 98% of production, competition would be stifled leading to potential price manipulation affecting consumers across state lines - an issue they saw as clearly falling under federal jurisdiction. The dissenting justices feared this decision would undermine future attempts at regulating large corporations and protecting free trade.