## Facts

- G.S. Suppiger Co. owned a patent covering a machine for depositing salt tablets used in canning.
- Suppiger, through a subsidiary, leased the patented machines to canners and sold unpatented salt tablets designed for use in the machines.
- The machine leases conditioned the license to use the patented machine on the lessee’s agreement to use only the subsidiary’s unpatented salt tablets (a tie-in).
- Morton Salt Co., a competitor, sold salt tablets and made and leased salt tablet depositing machines alleged to infringe Suppiger’s patent.
- Suppiger sued Morton for patent infringement seeking an injunction and an accounting; the tie-in practice and its terms were undisputed.

## Issues

1. Whether a patentee that conditions use of a patented machine on exclusive purchase of the patentee’s unpatented consumables may obtain equitable relief for infringement.
2. Whether denial of equitable relief for this conduct depends on proving a statutory antitrust violation (e.g., under the Clayton Act).

## Decision

- The Supreme Court reversed the court of appeals and held that Suppiger’s tie-in practice constituted patent misuse.
- The Court held that, while the misuse continued, Suppiger could not obtain an injunction or an accounting for infringement of the patent.
- The Court ruled that withholding equitable relief did not require proof that the tie-in satisfied the Clayton Act’s competitive-injury threshold.
- The case was remanded on the understanding that enforcement could become available if the patentee abandoned the misuse and its effects dissipated.

## Legal Principles

- A patentee may not use a patent as an effective means to restrain competition in an unpatented product used with the patented invention.
- Using a patent to secure a limited monopoly over unpatented goods beyond the patent grant is contrary to public policy reflected in the patent system.
- Courts of equity may withhold enforcement when the plaintiff’s asserted right is being used contrary to the public interest, especially where relief would support continuation of the wrongful practice.
- Patent misuse renders the patent unenforceable in equity while the misuse persists; it does not necessarily invalidate the patent.

## Conclusion

The Court applied the patent misuse doctrine to bar equitable enforcement where a patentee tied the right to use a patented machine to exclusive purchase of unpatented consumables, and it held that this bar operates without requiring a separate showing of a statutory antitrust violation, lasting until the misuse is abandoned and its consequences have dissipated.


Morton Salt Co. v. G.S. Suppiger Co., 314 U.S. 488 (1942)