Federal Circuit Reverses-In-Part Based on Claim Construction

In Sigray, Inc. v. Carl Zeiss X-Ray Microscopy, Inc., No. 2023-2211 (Fed. Cir. May 23, 2025), the Federal Circuit reversed-in-part and vacated-in-part a PTAB determination finding all claims of a patent owned by Carl Zeiss X-Ray Microscopy, Inc. valid in an inter partes review filed by Sigray Inc.

Sigray requested review of all claims of Zeiss’s patent, which detail projection magnification of x-ray images. Sigray’s invalidity grounds relied on Jorgensen, a paper describing a process to minimize X-ray magnification. Zeiss disputed whether Jorgensen disclosed the claimed “magnification of the projection X ray stage ... between 1 and 10 times.” The Board relied on expert testimony that Jorgensen’s X-rays have no “meaningful divergence,” are “essentially parallel,” and only exhibit “a very small angle” of divergence to find Jorgensen did not disclose “between 1 and 10 times” magnification. The Board held that Jorgensen did not anticipate claims 1, 3, and 4 and that claims 1-6 were not obvious.

The Federal Circuit disagreed. The Court reasoned the Board had narrowly construed “between 1 and 10”—despite the Board’s statement that it did not construe the claims. It found the Board’s decision to be based on the incorrect “belief that small amounts of divergence, and therefore magnification, are outside the claim.”

The Court reversed the Board’s determination that Jorgensen did not anticipate claims 1, 3, and 4, and it vacated and remanded the finding of non-obviousness of claims 2, 5, and 6 over Jorgensen.