United Shoe Machinery Corporation (USMC) (defendant) was the leading manufacturer of machinery for making shoes. However, USMC never sold machinery to customers and only allowed customers to lease machinery. The leasing agreements were long term and tended to discourage the lessees from switching to USMC’s competitors. The United States (plaintiff) sued USMC, alleging that USMC had monopolized the market for shoe machinery in violation of the Sherman Act. The government sought a consent decree that would require USMC to end the monopolizing practices. At the time, USMC controlled over 75 percent of the market for shoe-making machinery. USMC argued that its market share had been obtained lawfully and that USMC had not abused its position as a market leader to exclude competition.