Anders als im Europäischen Patentraum kann im US-Patentrecht bereits ein Verkauf unter Geheimhaltung patentschädigend sein und der sogenannten „on sale bar“ unterliegen.
„The FCAC concluded that “if the existence of the sale is public, the details of the invention need not be publicly disclosed in the terms of sale” for the on sale bar to apply. This ruling may not make the on sale bar absolute – if the existence of a sale is itself secret, it appears to fall outside the reasoning of the FCAC – but it does make it clear that a number of situations of practical interest may be caught by the on sale bar.“
(Quelle: https://ipcopy.blog/2019/02/05/nobody-knows-just-we-two-patents-sales-and-confidentiality/)