Guest Post by Profs. Masur & Ouellette: Private Third-Party Sales as Prior Art
Patent – Patently-O 2025-10-31
Summary:
Guest post by Professors Jonathan S. Masur (UChicago Law) and Lisa Larrimore Ouellette (Stanford Law).
In our 2024 Stanford Law Review article, “Real-World Prior Art,” we argued that the doctrines surrounding the public-use and on-sale bars—categories of prior art that we collectively called “real-world” prior art—were in some respects confused and misaligned. One of our arguments was that private sales—sales in which the invention has not been put into public use or led to the creation of some other type of prior art—should not provide the seller with a safe harbor against prior art under post-AIA 35 U.S.C. § 102(b)(1)(B), because a private sale by itself does not “publicly disclose” the invention per the terms of the statute. Not long after the publication of our article, the Federal Circuit held just that, in an excellent opinion by Judge Dyk, Sanho Corp. v. Kaijet Tech. Int’l Ltd., 108 F.4th 1373 (Fed. Cir. 2024).
A related argument in our paper—perhaps the central argument—was that the on-sale bar should be “party-specific.” That is, a sale by Aleida, by itself, should not bar independent inventor Bruno from obtaining a patent.