Facts of the Case
The Congress passed the Sherman Anti-Trust Act in 1890 as a response to the public concern in the growth of giant corporations controlling transportation, industry, and commerce. The Act aimed to stop the concentration of wealth and economic power in the hands of the few. It outlawed "every contract, combination...or conspiracy, in restraint of trade" or interstate commerce, and it declared every attempt to monopolize any part of trade or commerce to be illegal. The E.C. Knight Company was such a combination controlling over 98 percent of the sugar-refining business in the United States.
Did Congress exceed its constitutional authority under the Commerce Clause when it enacted the Sherman Anti-Trust Act?
The Act was constitutional but it did not apply to manufacturing. Manufacturing was not commerce, declared Fuller for the majority; the law did not reach the admitted monopolization of manufacturing (in this case, refining sugar). Although American Sugar had monopolized manufacturing, the Court found no violation of the Sherman Act because the acquisition of the Philadelphia refineries involved intrastate commerce. The trust did not lead to control of interstate commerce and so "affects it only incidentally and indirectly."