Precision Instrument Mfg. Co. v. Automotive Maintenance Machinery Co., 324 U.S. 806 (1945)
Precision Instrument is a cornerstone of patent equity jurisprudence that extends the traditional unclean hands doctrine into the patent arena with uncommon rigor. The Supreme Court emphasized that the patent system is imbued with a strong public interest; patents grant limited monopolies that courts will not enforce for those who compromise the integrity of the administrative process.
May a party that knowingly suppressed evidence of perjury and fraud in Patent Office interference proceedings obtain equitable relief to enforce private agreements or patent rights that depend upon the tainted proceedings?
A party seeking relief in equity must come with clean hands. In the patent context, because of the overriding public interest in the integrity of the patent system, applicants, patentees, their assignees, and their attorneys owe a duty of the highest candor and good faith in all dealings with the Patent Office. Courts of equity will not assist a party who has engaged in, benefited from, or knowingly suppressed fraud or perjury used to procure or maintain a patent, and they will deny enforcement of private arrangements and claims intimately connected with such misconduct.
No. AMMCO's knowing suppression of perjury in the Patent Office tainted its claims. Under the unclean hands doctrine, the Court barred AMMCO from obtaining equitable relief to enforce rights dependent on the tainted proceedings and directed dismissal of its claims.
Precision Instrument is a foundational case for the unclean hands doctrine in patent law and the modern duty of candor to the Patent Office. It teaches that courts will deny equitable relief where the plaintiff's conduct compromises the integrity of the patent system—whether or not the plaintiff originally committed the fraud—if the plaintiff knowingly suppressed it. The case is frequently cited alongside Keystone Driller and Hazel-Atlas to underscore that private settlements cannot sanitize or conceal fraud on the Patent Office and that the public interest in the patent system's integrity overrides parties' private bargains. For law students, it illuminates the intersection of equity and intellectual property, the ethical duties of attorneys before administrative agencies, and the remedial consequences—dismissal and nonenforcement—when those duties are breached.