In Hunting Titan, Inc. v. DynaEnergetics Europe GmbH, Case Nos. 2020-2163, 2020-2191 (Fed. Cir. Mar. 24, 2022), the Federal Circuit affirmed a decision of the Precedential Opinion Panel of the USPTO that vacated the denial of a motion to add substitute claims to a patent challenged by Hunting Titan in an IPR. At issue was whether the Patent Trial and Appeal Board acted within the bounds of its authority when it sua sponte found the substitute claims anticipated when such grounds were not raised by Hunting Titan. Although the decision of the Precedential Opinion Panel was affirmed, the Federal Circuit suggested that this was the result of a procedural failure on the part of Hunting Titan to challenge the Panel’s decision as an abuse of discretion, and not because of the substantive rationale of the Panel. As to the question of the Board’s authority to arrive at a decision on a patentability issue sua sponte, the Federal Circuit suggested that when there is “readily identifiable and persuasive” evidence relating to patentability based on the prior art of record, as the facts of this case suggest, the Board should sua sponte identify patentability issues for proposed substitute claims.