Winans v. Denmead
| Winans v. Denmead | |
|---|---|
| Argued January 16, 1854 Decided February 9, 1854 | |
| Full case name | Winans v. Denmead |
| Citations | 56 U.S. 330 (more) |
| Holding | |
| Established the doctrine of equivalents: Even if the challenged device is not literally within the claims of the prior art's patent, the challenged device infringes if it arrives at the same result in the same way. | |
| Court membership | |
| |
| Case opinions | |
| Majority | Curtis, joined by McLean, Wayne, Nelson, Grier |
| Dissent | Taney, Catron, Daniel |
| Dissent | Campbell |
Winans v. Denmead, 56 U.S. 330 (1854), was a United States Supreme Court case in which the court established the doctrine of equivalents. It held that, even if the challenged device is not literally within the claims of the prior art's patent, the challenged device infringes if it arrives at the same result in the same way.[1][2][3][4]
Background
Winans sued Denmead in the Circuit Court of the United States for the District of Maryland for an infringement of his patent in "an improvement in cars for the transportation of coal," granted on June 26, 1847. The case was decided there in favor of Denmead. Winans appealed to the Supreme Court on a writ of error.[1]
Opinion of the court
The Supreme Court was argued at the Supreme Court on January 16, 1854. The court issued an opinion on February 9, 1854.[5] The majority was concerned with treating the earlier inventor fairly in the face of unscrupulous infringers. The dissent by Campbell was concerned about the negative effects of construing patents as broader than their text.[2] Justices Taney, Catron, and Daniel dissented without a separate opinion.[1]
Later developments
The doctrine of equivalents continues to be good law. It has been considered in numerous cases since Winans, including Consolidated Safety-Valve Co. v. Crosby Steam Gauge & Valve Co. (1885),[6] which upheld a patent on a subsequent invention that was substantially similar to prior art because the subsequent invention was practically valuable and adopted widely, whereas the prior art was not so successful.[7] In later cases, courts clarified that there must be some "nexus" between the commercial success of the product and the patented subject matter for that sort of claim to survive the doctrine of equivalents.[6]
References
- ^ a b c Winans v. Denmead, 56 U.S. 330 (1854).
- ^ a b Morriss, Andrew P.; Nard, Craig Allen (January 2011). "Institutional Choice & Interest Groups in the Development of American Patent Law: 1790–1865". Supreme Court Economic Review. 19: 143–244. doi:10.1086/664565. ISSN 0736-9921.
- ^ Meurer, Michael; Nard, Craig (January 2005). "Invention, Refinement and Patent Claim Scope: A New Perspective on the Doctrine of Equivalents". Georgetown Law Journal. 93: 1947.
- ^ Fox, Isabel (September 30, 2021). "Evolution of the Doctrine of Equivalents through Case Law - Gallium Law". Retrieved January 19, 2026.
- ^ "Dates of Supreme Court decisions and arguments United States reports volumes 2 – 107 (1791 – 1882)" (PDF). Archived from the original (PDF) on June 10, 2010.
- ^ a b Silfen, Molly R.; Kazhdan, Daniel (July 2, 2020). "INVENTORS BEWARE: THE DANGER OF GETTING TOO MANY PATENTS". Santa Clara Law Review. 60 (2): 289. ISSN 0146-0315.
- ^ John F. Duffy, Reviving the Paper Patent Doctrine, 98 Cornell L. Rev. 1359 (September 2013).
External links
This article incorporates written opinion of a United States federal court. As a work of the U.S. federal government, the text is in the public domain.