Takeaway: The Federal Circuit ruled that a patent application’s filing date, not publication date, determines its prior-art status, underscoring the Patent Act’s unique treatment of applications and acting as a reminder to prioritize filing dates in patent disputes.

The Federal Circuit ruled that the filing date of a patent application, not its publication date, determines its status as prior art under the Patent Act. This decision, made in an appeal involving Lynk Labs’ LED patent claims, upheld the Patent Trial and Appeal Board’s finding that a patent application filed before Lynk Labs’ priority date but published after could invalidate its claims. The court clarified that patent applications have a special status under the law, differing from other printed publications.

Judge Sharon Prost emphasized that the Patent Act allows a patent application filed before an invention’s priority date to serve as prior art, even if published later. Lynk Labs’ argument against this interpretation was deemed unconvincing, particularly regarding the treatment of patent applications that later become patents or printed publications.

The successful challenge, brought by Samsung Electronics, involved a prior art application that was abandoned and never issued as a patent. Additionally, Lynk Labs lost on two claim construction challenges in the same appeal. In a separate case on the same day, the Federal Circuit affirmed another PTAB decision invalidating Lynk Labs’ LED patent claims in a challenge by Home Depot. None of the parties commented on the rulings.