The Federal Circuit recently affirmed a determination of inequitable conduct in GS Cleantech Corp. v. Adkins Energy LLC. Although inventors had been warned of the on-sale bar (requiring an invention not be sold or offered for sale more than one year before filing), the inventors initially did not disclose a relevant offer. The Federal Circuit affirmed the district court’s conclusions that: plaintiff CleanTech knew the offer threatened patenting and took steps to hide it from the USPTO; the inventors and plaintiff’s patent firm (“firm”) withheld evidence and made false representations to the USPTO; CleanTech and the firm attempted to coerce support for their false representations; the inventors and the firm prepared a “patently false” declaration; and they failed to correct the false declaration. Notably, the Federal Circuit affirmed the district court’s conclusion that “[t]he only reasonable inference is that [the firm] believed the [I]nventors had made an offer and, … they chose advocacy over candor.”