IP Law Daily, PATENT—Fed. Cir.: PTAB failed to properly consider Google’s obviousness arguments in IPR, Federal Circuit holds, (Jul 14, 2026)

By Steven Melendez

The appellate court returned the matter to the Board, finding it failed to consider prior art in combination and to explain alleged discrepancies with other related IPRs.

The Federal Circuit vacated and remanded a decision by the Patent Trial and Appeal Board (PTAB) in an inter partes review (IPR) requested by Google LLC of a Parus Holdings, Inc. patent. The appellate panel found the PTAB failed to consider prior art elements presented by Google in combination with one another and failed to explain why its decision appeared to contradict other related IPRs (Google LLC v. Parus Holdings, Inc., No. 24-2381 (Fed. Cir. Jul. 13, 2026)).

Background. Parus owns U.S. Patent No. 6,721,705, related to a voice-operated system for internet browsing and titled “Robust Voice Browser System and Voice Activated Device Controller.” The company also holds two other patents descended from the ‘705 patent and sharing its specification.

The ‘705 patent describes a system with categories of information that might be sought by a user and, for each category, a ranked list of relevant websites. When a user requests certain information, the system accesses the websites in rank order to search for relevant information. The system also keeps its ranked lists in order by using a “polling mechanism” that “continually polls or ‘pings’ each of the sites,” adjusting the websites based on whether they provide “useful and error-free” responses and speed of response.

Google petitioned for inter partes reviews of the patents, challenging claims on grounds of obviousness and pointing to similar combinations of prior art along with rationales for obviousness for the two patents. In the two other IPRs, the PTAB held all the challenged claims were unpatentable for obviousness, and those decisions were affirmed by the Federal Circuit in 2025. But in the ‘705 patent IPR, the PTAB found Google failed to show unpatentability of the claims at issue, claims 1 and 2, for which claim 1 was treated as representative.

Google alleged obviousness based on a combination of “Kovatch,” a patent application titled “Interactive Voice Response System” and recorded as a Patent Cooperation Treaty application, No. WO 01/50453. J.A. 364 and “Burrows,”U.S. Patent No. 5,765,149, which is titled “Modified Collection Frequency Ranking Method;” and a combination of “Wise,” U.S. Patent No. 5,884,262, titled “Computer Network Audio Access and Conversion System,” and Burrows.

The PTAB found that Google failed to show three claim limitations—1H, 1I, and 1J—would be obvious based on either the Kovatch-Burrows or Wise-Burrows combination. Google appealed to the Federal Circuit, arguing the PTAB made three errors by considering the prior art in isolation rather than in combination, by adopting a claim construction of the term ”unexpected response” without providing notice or opportunity to address that construction, and by failing to address Google’s arguments that the ruling was inconsistent with the ruling on the descendant patents.

Prior art. Google argued that the PTAB focused too much on Burrows rather than its combination with Kovatch or Wise. Kovatch also relates to a voice-operated system for accessing internet information and, Google asserted, discloses ranking websites, discussing “a hierarchical order based on users’ preferences.” And Burrows discloses ranking websites in a search response based on how frequently search terms appear on each site. It also discloses marking inaccessible websites as deleted, detecting website modifications, and optimizing query parsing to minimize search response time. Google alleges that an artisan would have used those concepts from Burrows to modify the website ranking taught by Kovatch.

The PTAB rejected that argument, finding Burrows had “no sense of ranking prior to a query.”

The Wise patent also relates to a telephone-operated computer system, describing indexing audio-compatible files where the “index may be stored as one or more documents preferably in a hierarchical order,” arguing Burrows’ numbered ranking could be applied to Wise by an artisan to include rank numbers in the hierarchical order. The PTAB similarly found that didn’t apply since ranking in Burrows only comes after a query.

The Federal Circuit agreed with Google that the PTAB improperly concentrated on Burrows alone and not how an artisan could modify the other teachings based on Burrows. “We cannot say that the deficiencies in the Board’s analysis were harmless, so we remand for the Board to consider the particular combinations presented by Google’s petition,” the appellate court ruled.

Claim construction. Google also argued the PTAB construed the term “unexpected response” in the claim and failed to afford it the opportunity, required by the Administrative Procedure Act (APA), to address the construction.

A claim limitation in the ‘705 patent requires decreasing a website rank “if an unexpected response is received” from the site. Google argued this would have been obvious based on Burrows teaching detecting website modifications, which the company said an artisan would know is an “unexpected response.” The PTAB rejected this argument, citing evidence that websites changed frequently at the time, finding Google hadn’t shown a modified website is an unexpected response.

The Federal Circuit found this reasoning was claim construction, relying on evidence to which claim construction typically concerns, and an IPR petitioner is entitled to reply to proposed claim constructions under the APA. This opportunity was denied to Google, according to the ruling.

Inconsistent rulings. Google asserted that it informed the PTAB about earlier IPR rulings involving the descendent patents and asked that it similarly hold the ‘705 patent unpatentable to avoid ruling inconsistently with the factfinding in those earlier rulings with regard to the Wise-Burrows combination.

The Federal Circuit has previously ruled that “the APA may be violated when an agency adjudicator treats similar cases differently, at least when it does so without explaining why it has reached apparently discrepant results.” And the PTAB’s failure to address the issue makes it impossible to determine its rationale on appeal, according to the ruling.

“On remand, if the Board reaches the Wise-Burrows ground and again determines that the challenged claims are not unpatentable, it should expressly address Google’s inconsistency argument and explain why it thinks this case relevantly different from the earlier IPRs or otherwise justify now reaching a different result,” according to the ruling.

The Case is No. 24-2381.

Judge: Taranto, R.

Attorneys: Benjamin Haber (O'Melveny & Myers LLP) for Google LLC. John Bruce Campbell (McKool Smith, PC) for Parus Holdings, Inc.

Companies: Google LLC; Parus Holdings, Inc.

Cases: Patent FedCirNews