Google LLC v. Valtrus Innovations Ltd.

Google v. Valtrus Innovations, decided October 19th, 2026. A precedential panel of the Federal Circuit, in an opinion by Judge Cunningham, affirmed a decision of the Patent Trial and Appeal Board that Google had not shown any claim of a Valtrus patent unpatentable. The court held that metadata generated by Microsoft Word can independently corroborate an inventor's testimony of conception, and that substantial evidence supported the inventors' reasonably continuous diligence. Here's the brief.

Valtrus owns the ’704 patent, which claims methods for merging search-result lists from multiple search engines. The application was filed on August 27th, 2001, so the pre-AIA, first-to-invent version of section 102 governs.

Google petitioned for inter partes review of claims 1 through 23, arguing obviousness. Every one of its grounds relied on a reference called Bushee, a U.S. patent filed on July 24th, 2001, about five weeks before Valtrus's application.

Valtrus responded by antedating Bushee. It argued that its inventors conceived the invention before Bushee was filed, so Bushee was not prior art under pre-AIA section 102(e). To prove the earlier date, Valtrus offered a declaration from co-inventor Dr. Tsaparas, the original invention-disclosure documents, and the Microsoft Word metadata of those files.

The Board accepted that showing. It found an invention date before Bushee's filing and diligence through the filing of the application, and it concluded that Bushee was not prior art. Without Bushee, Google had not shown any claim unpatentable. Google appealed.

Google raised two challenges: that the evidence corroborating the inventor's testimony was legally insufficient, and that substantial evidence did not support the Board's diligence finding.

The framework is settled. A patent owner can antedate a reference by showing conception before the reference was filed, and reasonably continuous diligence from just before that date until its own filing.

When conception rests on an inventor's testimony, there is an added requirement.

Corroboration is judged under a rule of reason, examining all pertinent evidence. Its sufficiency is a question of fact, so the court reviewed the Board's findings for substantial evidence.

The court affirmed on both issues.

On corroboration, Google argued that the declaration, the disclosure documents, and their metadata all came from Dr. Tsaparas himself, and so could not independently corroborate him. The court disagreed. Assuming without deciding that the metadata was authentic, the court reasoned that metadata generated by Microsoft Word was not authored by the inventor. It relied on its 2025 decision in Global Health Solutions v. Selner.

The court distinguished unwitnessed laboratory notebooks and unwitnessed emails and drawings, which alone cannot corroborate conception. Here, the authorship and timestamp information was consistent with the conception date in the declaration. And Google's counsel acknowledged at oral argument that a human is not a required element for corroboration.

On diligence, Google disputed only the final stretch, from August 8th, when the last inventor signed, to the August 27th filing. By Google's count, about eleven business days. Dr. Tsaparas was in Ontario, and his signed declaration had to travel by mail to the law firm in California. Valtrus's expert testified that law firms take several weeks or more to draft and finalize an application. The court found that substantial evidence.

The court found Google's reliance on In re Mulder misplaced. In Mulder, the record showed no activity of any kind in this country for nearly three months.

Google v. Valtrus confirms that corroboration of an inventor's conception testimony need not come from another person. Metadata that software generates automatically is independent of the inventor's own statements and documents, and it can supply that corroboration, unlike an unwitnessed notebook. The decision also reaffirms that diligence must be reasonably, not perfectly, continuous, and that the ordinary time a law firm needs to complete, execute, and file an application can satisfy it.

Google LLC v. Valtrus Innovations Ltd., No. 2024-1945, decided October 19th, 2026. I'm Kyle Coleman. Thanks for watching.