IP Law Daily, PATENT—Fed. Cir.: PTAB’s invalidation of voice input control patent claims affirmed on appeal, (Apr 14, 2026)

By Justin Marcus Smith, J.D.

Patent Trial and Appeal Board correctly decided that some specific patent claims related to dynamic audio volume output control were unpatentable as obvious.

In a non-precedential decision, the United States Court of Appeals for the Federal Circuit affirmed a Patent Trial and Appeal Board (Board) decision that some specific patent claims related to dynamic audio volume output control were unpatentable as obvious. The reasoning the Board adopted was not untimely because the Roku, Inc. inter partes petition articulated the reasoning from inception. The Board did not err in finding that the appellant, Universal Electronics Inc. (UEI), raised an argument that did not address the combination of prior art references that Roku, Inc. (Roku) proposed. The Board articulated a reason why a person of ordinary skill in the art would be motivated to combine the prior art references based on substantial evidence. The Board did not commit reversible legal error in finding a motivation to combine prior art references because Roku only needed to show the combination was a suitable option, it did not have to be the best option. Last, the Board did not err in relying on precedent that did not require each piece of prior art in an asserted combination to be directed to the same known problem. Roku’s expert and petition explained there was a known problem; prior art helped to address that problem; and combining the prior art was not beyond the skill of a person of ordinary skill (Universal Electronics, Inc. v. Roku, Inc., No. 24-1426 (Fed. Cir. Apr. 10, 2026)).

Background. UEI appealed a final written decision of the Patent Trial and Appeal Board in an inter partes review brought by Roku. The Board determined that 14 specific claims of U.S. Patent No. 10,930,276 (‘276 patent), a patent which recited a method for directing voice input in a controlling device, were unpatentable as obvious. The PTAB determined that two other claims were not unpatentable as obvious, but they were not at issue on appeal.

Roku’s expert characterized the practical problem of art as the control of undesirable environmental noise that might interfere with a user’s enjoyment of audio produced by a device like a television. To that end, Roku’s petition proposed modifying another patent disclosure, Hart-787, of an audio modification engine with Fu’s predetermined (preset) audio threshold, then further modifying that combination such that the threshold would be further adjusted for background noise as taught in Rosenberg. In other words, Roku argued the Hart-787 disclosure left it to a person of ordinary skill in the art to determine when and how to compensate for background noise, where Fu and Rosenberg taught how best to do that for controlling devices by voice.

On appeal, UEI argued (1) the Board improperly adopted Roku’s proposed modification for the first time in the Roku reply; and (2) the PTAB finding that a person of ordinary skill in the art would have modified as Roku suggested was legally erroneous and lacked substantial evidentiary support. Applying de novo review, the Federal Circuit affirmed in light of substantial evidence and no legal error.

Petition adoption. The court held the Board did not improperly adopt a modification that Roku advanced for the first time in its reply because the premise was incorrect; the reasoning the Board adopted was in the Roku petition.

Inapplicable argument. The Federal Circuit did not find any reversible error in the Board finding that UEI raised an argument that did not address the combination Roku proposed. UEI had argued that Rosenberg’s volume threshold is set after the device receives and processes the user’s speech input, not before, as claimed. However, the Federal Circuit found the Board explained how the combination only used Rosenberg’s teaching about a threshold to be set based on dynamic ambient noise, while relying on teachings of other prior art for the use of that threshold.

Ordinary skill. The Federal Circuit held that substantial evidence supported the Board finding that a person of ordinary skill in the art would have been motivated to combine Rosenberg with Hart-787 and Fu. Rosenberg was at least suitable for considering the level of background noise, “unlike the preset threshold of Hart-787 and Fu.”

Roku expert testimony and disclosures of the references supported the Board finding. Specifically, Roku’s expert opined that Hart-787 left it to a user to adjust for background noise in real-time. The expert continued that Fu disclosed, in the same field of endeavor, volume output adjustment if background noise exceeds a preset threshold. Roku’s expert further explained that adjusting volume output based on background noise was “well-known in the art.” A person of ordinary skill would understand the option of either going with a desired preset threshold or a threshold adjusted for background noise, essentially modifying the Hart-787 and Fu preset method with the Rosenburg method of adjusting for background noise. The Board accepted Hart-787 and Fu as further modified by Rosenburg based on substantial evidence.

No error. The Board did not commit reversible legal error in finding a motivation to combine Hart-787 and Fu. The PTAB found it clear that Roku only needed to show the combination was a suitable option. Roku did not need to show it was the best option. Specifically, the Board explained that Roku showed, by a preponderance of the evidence, that Fu’s technique of improving the signal-to-noise ratio by adjusting volume based on a preset environmental noise threshold was a suitable option to replace the Hart-787 techniques.

In addition, the Board did not err in relying on the precedent of Intel Corp. v. PACT XPP Schweiz AG, 61 F.4th 1373 (Fed. Cir. 2023). UEI argued that, unlike the petition in Intel, the instant Board decision and the Roku petition contained nothing to show that both Hart-787 and Fu addressed the same known problem. However, the Federal Circuit determined that UEI misread Intel.Intel did not require that each piece of prior art in an asserted combination must be directed to the same known problem. Intel acknowledged a motivation to combine where there is a known technique for a known problem using prior art elements based on established functions. Intel also further reiterated the “well-known” principle that a need or known problem at the time of invention, and addressed by the patent, can provide a reason for combining elements as claimed.

Furthermore, substantial evidence supported the Board finding that Fu’s technique to improve the signal-to-noise ratio (SNR) was a suitable option to replace the Hart-787 techniques. The Board relied on Roku’s petition. The petition argued that (1) Hart-787 left it to a user to use known audio output volume adjustment techniques based on ambient noise volumes detected in real-time; and (2) a person of ordinarily skill in the art would have used Fu, in the same field of endeavor, to achieve the Hart-787 goal of improving SNR without lowering the volume of the wirelessly-linked audio-producing device if it were unnecessary to do so. The Roku expert declaration and Fu disclosures supported the Board finding that Fu could replace Hart-787.

Remaining UEI arguments were unpersuasive, and the Federal Circuit affirmed the Board decision accordingly.

The Case is No. 24-1426.

Judge: Cunningham, T.

Attorneys: Michael Nicodema (Greenberg Traurig, P.A.) for Universal Electronics, Inc. Elizabeth DiMarco (Wolf, Greenfield & Sacks, PC) for Roku, Inc.

Companies: Universal Electronics, Inc.; Roku, Inc.

Cases: Patent FedCirNews USPTO