Google v. Valtrus — Federal Circuit Says Word Metadata Can Corroborate Earlier Invention

Background

Valtrus Innovations owns U.S. Patent No. 6,728,704, which covers techniques for combining result lists from multiple search engines. Google challenged all 23 claims in an inter partes review (IPR), an administrative proceeding in which the Patent Trial and Appeal Board can cancel patent claims that should not have issued.

Google’s obviousness challenge depended on an earlier-filed patent application known as Bushee. Although Bushee was filed about five weeks before the application that became the ‘704 patent, Valtrus invoked the pre-2013, first-to-invent version of patent law. Under that system, a patent owner could remove a reference as prior art by proving an earlier conception date and reasonably continuous diligence through the filing of its own application.

To prove earlier conception, Valtrus relied on a co-inventor’s declaration, original invention-disclosure documents, and Microsoft Word metadata associated with those documents. The Board found that this evidence established conception before Bushee’s filing and that the inventors and their patent counsel acted with sufficient diligence until the ‘704 application was filed. Because Bushee therefore was not prior art, the Board concluded that Google had not shown any challenged claim unpatentable.

The Court’s Holding

The Federal Circuit affirmed. Writing for a unanimous panel, Judge Tiffany Cunningham held that substantial evidence supported the Board’s finding that the inventor’s account was independently corroborated. The court explained that automatically generated Microsoft Word metadata is not authored by the inventor. Its authorship and timestamp information therefore can serve as independent evidence supporting an inventor’s testimony and the contents of an invention disclosure.

The panel rejected Google’s comparison to unwitnessed laboratory notebooks or drawings, which ordinarily cannot corroborate an inventor’s testimony by themselves. Applying the flexible “rule of reason,” the Board was entitled to consider all the evidence together. The metadata was consistent with the claimed conception date and supported the credibility of the inventor’s account. The court assumed without deciding that the metadata was authentic because authenticity was not necessary to resolve the legal question presented.

The court also upheld the Board’s diligence finding. Google focused on an approximately three-week period after the last inventor signed the application papers and before counsel filed the application. The record showed that one inventor was in Canada and had to return a physical signature to counsel in California. Expert testimony also explained that law firms commonly need several weeks to finalize a patent application. Patent law requires reasonably continuous diligence, the panel emphasized, not proof of work on every calendar day. The evidence accounted for the disputed period and showed no abandonment or unreasonable delay.

Key Takeaways

• Automatically generated document metadata can independently corroborate an inventor’s testimony about when an invention was conceived.
• The corroboration inquiry remains holistic: the Board may evaluate metadata, underlying documents, testimony, and surrounding circumstances together under the rule of reason.
• Reasonably continuous diligence does not require activity every day. Mailing time, attorney workflow, and other practical steps can explain short gaps before filing.
• The ruling applies the pre-America Invents Act first-to-invent rules, so its direct priority analysis matters chiefly to patents and applications governed by the older law.

Why It Matters

The decision gives patent owners and challengers concrete guidance about digital evidence in priority disputes. Ordinary office-file metadata can do more than establish provenance: when properly supported, it can supply the independent corroboration needed to validate an inventor’s recollection. Companies should preserve native invention-disclosure files, document-management records, and associated metadata rather than retaining only printed or flattened copies.

The ruling also reinforces the practical nature of diligence. A short administrative gap will not necessarily defeat an earlier invention date when the record explains what was happening and shows the application was moving toward filing. Here, those findings kept Bushee out of the prior-art analysis and preserved all challenged claims of Valtrus’s search-engine patent.