United States v. Grinnell Corporation

Grinnell Corporation (defendant), a plumbing and fire-sprinkler manufacturer, controlled three companies (defendants) that together held over 87 percent of the national market for accredited central-station fire and burglary alarm services, which used guard-staffed monitoring stations around the clock and earned subscribers lower insurance premiums than less reliable alternatives like watchmen or unaccredited services. The United States sued Grinnell and its subsidiaries for violating §§ 1 and 2 of the Sherman Act. Grinnell argued the relevant product market should include all forms of home protection, not just accredited central-station services, and that the relevant geographic market should be defined locally rather than nationally since these services protect fixed properties. The district court found per se Sherman Act violations, and the defendants appealed to the Supreme Court.