International Salt Company v. United States

International Salt Company (International Salt) (defendant) leased patented industrial salt-processing machinery on terms requiring lessees to buy unpatented salt tablets exclusively from International Salt for use in the machines; some leases let International Salt instead match the lowest market price rather than let the lessee buy elsewhere. The United States (plaintiff) sued, alleging the leases were unlawful tying arrangements under the Sherman and Clayton Acts. International Salt argued the arrangement created no monopoly since lessees could sometimes buy elsewhere, and that the purchase requirement simply ensured machine quality by guaranteeing suitably pure salt. The district court granted summary judgment for the United States, and International Salt appealed directly to the Supreme Court.