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