TAKEAWAY: A single early conversation, demo, or sale, even a confidential sale under NDA, may forfeit patent rights in the United States if not followed promptly by a patent application filing.
Under U.S. patent law, an invention may risk loss of patentability if it is publicly disclosed, used, or sold before the effective filing date of a patent application, unless a grace period exception is applicable. A disclosure of that kind becomes prior art that may be used not only to show lack of novelty under 35 U.S.C. § 102, but also as the basis for an obviousness rejection under 35 U.S.C. § 103. The America Invents Act (AIA) codified this at 35 U.S.C. § 102(a)(1), which bars patents on inventions that were “patented, described in a printed publication, or in public use, on sale, or otherwise available to the public” before the application’s effective filing date.
Two features of the on-sale bar are worth understanding precisely. First, the bar is triggered only where the invention was the subject of a commercial sale or offer for sale, not primarily for experimental purposes, and was ready for patenting at that time (a two-part requirement that does a great deal of work in practice). Second, the sale need not be public. The law does offer two safety valves, but narrower ones than most applicants assume. The first is experimental use: a sale or use undertaken primarily to test whether the invention works for its intended purpose may not trigger the bar. The second is the statutory grace period. Section 102(b)(1) removes from the prior art disclosures made one year or less before the effective filing date where the disclosure was made by the inventor or by someone who obtained the subject matter from the inventor, and, separately, where a third party’s disclosure falls within that same one-year window and follows a public disclosure of the same subject matter by the inventor. That second exception is thinner than it sounds: it does not apply where the subject matter relied on as prior art differs from what the inventor previously disclosed publicly, even if the only differences are mere insubstantial changes or only trivial or obvious variations. What the grace period does not do is excuse an independent third party’s disclosure at all, whether that disclosure falls inside or outside the one-year window, unless the inventor publicly disclosed the same subject matter first. It is a shield for an applicant’s own prior public disclosures of the invention, not a twelve-month cushion against the rest of the world.
Nondisclosure agreements (NDA) may help in maintaining the confidentiality of a disclosed invention, but these agreements may offer weaker protection than most applicants assume. A sale kept secret under an NDA is still a sale for on-sale bar purposes in the United States. And while a genuinely confidential, enforceable NDA generally means information has not been “made available to the public,” that protection depends entirely on the obligation holding, as well as on the applicant’s ability to prove later that it did. Leakage, undocumented conversations, and informal follow-ups relating to the subject invention routinely undo the protection. Leakage, in this context, may include situations where details of the invention reach people who are outside the agreement and under no duty of confidentiality (e.g., a demonstration attended by guests who did not sign, a slide deck forwarded beyond its intended recipients, or specifics repeated at a trade show, in a pitch meeting, or online). Once that happens, the information may be treated as publicly available no matter what the signed agreement says.
The practical implication is that patent strategy needs to run in parallel with business development, not behind it. Filing a U.S. patent application before conducting various actions, including but not limited to, entering supplier discussions, running customer pilots, exhibiting at trade shows, or discussing pricing and pre-orders, may help preserve flexibility in the United States. A U.S. provisional application may offer a strategic instrument for preserving a priority date prior to any potential public disclosures, with one caveat: it secures a date only for what it actually describes and enables.
Where timing is tight or a multinational filing is likely, early consultation with counsel (including foreign counsel where relevant) is the most reliable way to keep options open.