NCS Multistage Inc. v. Nine Energy Service, Inc.

NCS Multistage v. Nine Energy Service, decided September 14th, 2026. A precedential panel of the Federal Circuit, in an opinion by Judge Cunningham, addressed the America Invents Act's grace period. The court held that a patentee's private sale of its device to a single customer was not a public disclosure that shields the patent from intervening prior art. A competitor's later sale was therefore prior art as a matter of law. The court vacated a jury verdict for the patentee and ordered a new trial. Here's the brief.

NCS owns the ’445 patent, which claims a float tool used in oil and gas wells. A rupture disc seals the casing so it floats into a deep or horizontal wellbore, then gives way under pressure. The patent claims priority to a provisional application filed February 5th, 2013, and the parties agreed that the post-AIA version of section 102 applies.

NCS sued Nine Energy for infringement. Nine's main prior-art defense was a tool sold by a company called TCO to Apache in August 2012, within a year before NCS's priority date.

NCS answered with the grace period. In July 2012, before TCO's sale, NCS had sold its own device, the AirLock, to a customer named Tundra. That sale, NCS argued, was a public disclosure that removed TCO's later sale as prior art.

The jury found infringement and no invalidity, and the district court entered judgment for NCS. Nine appealed.

The question was whether the AirLock sale was a public disclosure within the meaning of that provision.

After the verdict, the Federal Circuit decided Sanho v. Kaijet in 2024. Sanho construed the identical language in the companion provision for patent disclosures, section 102(b)(2)(B). It rejected the argument that placing an invention on sale necessarily publicly discloses it.

Sanho distinguished commercial exploitation from a disclosure that puts the public in possession of the invention.

Applying Sanho, the court agreed with Nine.

As in Sanho, the AirLock was sold privately to a single party. There was no evidence that the devices were widely distributed or placed where the public could examine them. The AirLock was delivered in a sealed black tube that had to be cut open, and there was no evidence that receiving one would reveal the claimed rupture-disc arrangement. NCS's technical documents were marked confidential. There was no non-disclosure agreement, but there was also no teaching of the invention to anyone beyond Tundra.

The court also corrected two claim constructions. Internal diameter means a measured diameter across the width of the casing string, not an inner surface. And casing string carries no size limit: the district court's requirement that it customarily measure at least four and a half inches contradicted the specification and hinted to the jury how to resolve a factual dispute. It affirmed the exclusion of late-produced discovery. Because NCS had other invalidity theories, the court ordered a new trial rather than judgment, and it vacated the infringement and damages judgments.

NCS Multistage applies Sanho to the grace period of section 102(b)(1)(B). An inventor's earlier commercial activity does not automatically shield a patent from intervening third-party disclosures. The shield requires a disclosure that makes the invention available to the public. A private sale to one customer, without teaching the invention's relevant features to others, does not qualify. Like Sanho, the decision leaves open exactly what showing a sale requires.

NCS Multistage Inc. v. Nine Energy Service, Inc., No. 2025-1000, decided September 14th, 2026. I'm Kyle Coleman. Thanks for watching.