IP — Federal Circuit Tightens the Grace Period: What a Private Sale Means for Your Patent Rights

On September 14, 2026, the U.S. Court of Appeals for the Federal Circuit issued its decision in NCS Multistage Inc. v. Nine Energy Service, Inc., No. 2025-1000 (Fed. Cir. Sept. 14, 2026), reinforcing a critical limitation on the patent grace period under the America Invents Act.  The ruling confirms that a private sale of an invention, even one made without a confidentiality agreement and with physical delivery of the product, does not count as a “public disclosure” by the inventor that would shield the inventor from a third party’s sale before the filing date.

Background.  Under U.S. patent law, an invention that is sold, used, or made publicly available by another before the filing date of a patent application is “prior art” that blocks the patent.  However, there is a one-year grace period that may protect an inventor who has “publicly disclosed” the invention before those prior art events occur.  In the NCS Multistage case, the patent owner (NCS) sold its product to a single customer in July 2012.  The following month, an unrelated company (TCO) separately sold a similar product to another buyer.  NCS did not file its patent application until 2013, within one year of its sale.

NCS argued that its earlier sale should qualify as a “public disclosure” that would neutralize TCO’s intervening sale as prior art. The Federal Circuit disagreed, because NCS’s sale did not constitute a “public disclosure.”  The court held that the sale was a private transaction with a single buyer because the invention had not been made sufficiently available to the public, even absent a confidentiality agreement.  It should be noted that NCS’s product was delivered in sealed packaging, technical documents were marked confidential, and the product was not offered to the public at large.  The court held that TCO’s sale could not be excluded from the prior-art analysis, and the court vacated the jury’s $486,400 damages award.  The court also reversed two of the district court’s claim constructions and ordered a new trial on both infringement and invalidity. NCS may still argue on remand that TCO’s product did not actually embody the patent claims or was not a public disclosure either.

This decision follows the Federal Circuit’s ruling in Sanho Corp. v. Kaijet Technology International Ltd., 108 F.4th 1376 (Fed. Cir. 2024), which held that a private sale does not qualify as a “public disclosure” that triggers the grace period’s safe harbor.  Sanho in turn relied on the Supreme Court’s decision in Helsinn Healthcare S.A. v. Teva Pharmaceuticals USA, Inc., 586 U.S. 123 (2019), which held that even a confidential sale can qualify as prior art under the on-sale bar.  Together, these decisions confirm that private commercial activity can be used against an inventor while offering no protection against independent third-party disclosures.

Practical Implications.  For companies and inventors commercializing new technology, NCS Multistage carries three important takeaways.

First, file early.  Once an application, even a provisional, is filed, no public disclosure of what is disclosed in the application will jeopardize the patentability of the invention disclosed.  A public disclosure of an invention, including a qualified commercial sale, starts a one-year clock for seeking patent protection in the U.S. During that year, disclosures by the buyer or others in the chain of the inventor’s sale are protected and will not count as prior art.  However, as this case illustrates, if an unrelated third party independently develops and discloses the same invention during that window, a prior public disclosure by the inventor, not a private sale, may shield against it.  But such a public disclosure will jeopardize patent rights outside the U.S., which is why an early filing is recommended.

Second, ensure your provisional patent applications fully describe the invention.  In NCS Multistage, the court noted that NCS’s provisional application did not fully support certain final patent claims, which affected the applicable statutory framework.  A provisional that does not fully describe what you intend to sell or patent may not establish your effective filing date, and thus potentially exposes intervening third-party activity as prior art.

Third, keep your patent attorney informed of any sale, demonstration, or delivery of a product that embodies a new invention, especially before the patent application is on file.  These can include marketing teasers on social media.  Your attorney can assess whether an accelerated filing is advisable.

If you have questions about how this decision may affect your patent strategy, please contact the authors or the attorneys at Womble Bond Dickinson with whom you normally work.