The Federal Circuit has confirmed the application of the pre-America Invents Act (AIA) on-sale bar to AIA patents. This decision underscores the ongoing relevance of pre-AIA legal principles in the context of patents governed by the AIA. The ruling clarifies legal ambiguities regarding the on-sale bar, which prohibits patenting an invention that has been sold or offered for sale prior to the patent application date. Additionally, the Federal Circuit has provided further guidance on patent owner estoppel, emphasizing its scope and implications for patent litigation.