Opinions — Tuesday, June 9, 2026

The Federal Circuit affirmed the PTAB's decision upholding an obviousness rejection of claims 1–22 in Zhengxu He's patent application directed to an automated kitchen system that transports and unloads ingredient containers between storage and cooking stations. The examiner had rejected the claims as obvious over Buehler (disclosing an automated kitchen system) in view of He '660 (disclosing ingredient-cart-unloading apparatus and mini vehicles). He challenged the Board's motivation-to-combine finding, arguing that the rationales for combining the references were either contradicted by Buehler's teachings or would result in an incompatible system.

The court's analysis turned on the substantial evidence standard and the proper legal framework for evaluating combination obviousness. Reviewing motivation to combine as a factual question for substantial evidence, the court credited the Board's finding that He '660 disclosed explicit automation benefits—dependable delivery, minimized space and idle time, and reduced labor costs—and that the examiner adequately explained how incorporating He '660's vehicle and unloading features would achieve those benefits in Buehler's system. The court rejected He's "bodily incorporation" theory of incompatibility, reaffirming that the obviousness test asks what the combined teachings would have suggested to a skilled artisan, not whether one reference's physical structure can be inserted wholesale into another.

The Federal Circuit reversed the Board's final written decisions holding claims of Google's hotword-detection patents unpatentable in inter partes review proceedings initiated by Sonos. The patents address the problem of multiple smart devices responding to a single voice command by having devices exchange confidence scores while remaining in a low-power mode to determine which device should respond. The Board found the claims anticipated by or obvious over prior art reference Rosenberger, concluding that Rosenberger disclosed transmitting messages while devices remain in low-power mode.

The court held that substantial evidence did not support the Board's anticipation findings because Rosenberger's column 8 disclosure—on which the Board relied—never actually described exchanging weighted signals while devices remained in the low-power "listening" mode. The court rejected the Board's interpretation that conflated independent alternative conditions in Rosenberger as a causal sequence and found no support for reading a status light change as indicating a mode transition. The court declined to address Sonos's alternative theory that devices would be in some other (non-listening) low-power state during coordination, remanding for the Board to make fact findings on that theory in the first instance rather than conducting initial factfinding on appeal.