The US Court of Appeals for the Federal Circuit affirmed a Patent Trial & Appeal Board (Board) decision holding that the term “self-similar” was not indefinite and denying leave to file a sanctions motion. ClearOne, Inc. v. Shure Acquisition Holdings, Case No. 2021-1517 (Fed. Cir. June 1, 2022) (Moore, Newman, Hughes, JJ.)

Shure owns a patent relating to arrays of microphones and housings that can be fitted to a drop ceiling grid, providing “equivalent beamwidth performance at any given look angle.” During inter partes review, Shure moved to amend the claims to add a new claim reciting microphones “arranged in a self-similar configuration.” The Board granted that motion, holding that “self-similar” was not indefinite. The Board denied ClearOne’s motion for rehearing and separate motion for sanctions alleging a failure to disclose prior that Shure had asserted in a post-grant review initiated against one of ClearOne’s patents.

The Federal Circuit first reviewed the Board’s indefiniteness holding. Since “[d]efiniteness is a matter of claim construction,” the Court applied de novo review while reviewing underlying factual determinations for substantial evidence. The Court held that the intrinsic record alone supported the Board’s definiteness finding because it provided the scope of “self-similar” with reasonable certainty. The specification disclosed microphones arranged in a “self-similar or repeating configuration”; a “fractal, or self-similar, configuration surrounding a central microphone”; and arrangements in circular or other repeating shapes, such as “ovals, squares, rectangles, triangles, pentagons, or other polygons.” Thus, “self-similar,” when read in view of the specification, informed skilled artisans about the scope of the invention with reasonable certainty.

The Federal Circuit rejected ClearOne’s argument that “self-similar or fractal-like” and “self-similar or repeating” distinguished self-similar from other types of patterns, holding that in context, it was clear that the phrases equated, not juxtaposed, self-similar with those patterns. Reviewing the extrinsic evidence, the Court also rejected ClearOne’s arguments premised upon “a series of rhetorical questions to show [ClearOne’s] varying interpretations of the self-similar term.” The possibility of varying interpretations, the Court held, “does not render [a term] indefinite,” as otherwise nearly every term would be indefinite if susceptible to alternative plausible constructions.

The Federal Circuit also rejected ClearOne’s motion for leave to seek sanctions. The Board held that allowing the sanctions motion would lead to an inefficient proceeding because the sanctions motion raised the same arguments as the denied request for rehearing, a ruling that ClearOne conceded on appeal. The Board also found a lack of intent to breach a duty to disclose references. Without analysis and applying the abuse of discretion review standard, the Court found that these factual determinations sufficiently established that the Board did not abuse its discretion.