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Case Basics
Docket No. 
Wells Electronics, Inc.
(Argued the cause for the respondent)
(On behalf of the United States, as amicus curiae, supporting the respondent)
(Argued the cause for the petitioner)
Facts of the Case 

In 1980, Wayne K. Pfaff developed a new type of computer chip socket for Texas Instruments (TI). In early April 1981, TI confirmed they would order and use Pfaff's socket. No actual socket was made until July 1981. Pfaff applied for a patent in April 1982. A patent was not granted on Pfaff's socket until 1985. After the patent was issued, Pfaff sued Wells Electronics, who had developed a competing socket, for patent infringement. Pfaff claimed that Wells' socket infringed upon six of his patent's claims. The District Court held that Wells' socket violated three of Pfaff's patent claims. In reversing, the Court of Appeals held Pfaff had sold the socket to TI more than a year before he applied for a patent. Thus, Wells' socket did not infringe on Pfaff's under the Patent Act of 1952, which states that no one can patent an invention that has been on sale for more than one year before filing a patent application.


Does the confirmation of a commercial sale mark the beginning of the one year period inventors have to file for a patent, despite the fact the invention has not been produced?

Decision: 9 votes for Wells Electronics, Inc., 0 vote(s) against
Legal provision: 35 U.S.C. 102

Yes. In a unanimous decision, announced by Justice John Paul Stevens, the Court ruled federal patent law does not permit patents to be granted if an invention has been on sale for more than one year in this country before the patent application is filed. Moreover, a patent is on sale when a commercial sale offer has been made and when the inventor has made the invention, prepared drawings, or described the invention enough to be produced.

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PFAFF v. WELLS ELECTRONICS, INC.. The Oyez Project at IIT Chicago-Kent College of Law. 26 August 2015. <>.
PFAFF v. WELLS ELECTRONICS, INC., The Oyez Project at IIT Chicago-Kent College of Law, (last visited August 26, 2015).
"PFAFF v. WELLS ELECTRONICS, INC.," The Oyez Project at IIT Chicago-Kent College of Law, accessed August 26, 2015,