IP Law Daily, PATENT—Fed. Cir.: Patent decision against Centripetal affirmed for obviousness, two claims denied on obviousness grounds reversed., (Apr 24, 2026)

By Joe Cox, J.D.,

The appeal affirmed findings against Centripetal on 18 of 20 claims and then reversed the two findings of non-obviousness.

On Thursday, the U.S. Court of Appeals for the Federal Circuit affirmed a finding of the U.S. Patent and Trademark Office’s Appeal Board (Board) in regard to 18 of 20 claims in which the board ruled against Centripetal Networks, LLC (Centripetal), and then also reversed the two claims in which the board ruled for Centipetal on a finding of non-obviousness. The review came from Centripetal’s claims on U.S. Patent No. 10,193,917 (‘the 917 Patent’). Keysight Technologies, Inc. (Keysight) had filed the petition for review and was the cross-appellant on the two claims on which Centripetal had previously prevailed. Central to the decision was a discussion of whether the Board had erred in construing the term “packet flow” as well as the term “packet flow entry.” (Centripetal Networks, LLC v. Keysight Technologies, Inc., No. 24-1406 (Fed. Cir. Apr. 23, 2026)).

Centripetal had filed for the 917 Patent in disclosing a “packet-filtering device” that receives network packets and then determines if the packets correspond to criteria set by a packet-filtering rule, or whether they may correspond to network threat indicators. The packet filter then applies an operator which allows the packet to either continue forward to its destination or not. The packet filter then generates log data tracking its operation.

Keysight, at the initial hearing, established that 18 of the 20 claims in the 917 Patent would have been obvious either over a product called Sourcefire alone or some combination of Sourcefire and Macaulay. Sourcefire likewise monitors networks for attacks by examining packets for malicious activity. Sourcefire users create custom intrusion rules to determine if a packet is allowed to pass or is dropped, with a corresponding log being developed.

The Board found that Sourcefire had disclosed a packet flow entry, packet flow analysis data, a device that updated a packet flow entry based on a packet flow log entry, and that Sourcefire had disclosed a refresh interval to its packet flow entries.

Macaulay, the Board found, had disclosed an intelligence headquarters that produced refined cyber threat intelligence data pertaining to attributes indicative of a threat. That intelligence headquarters kept logs regarding particular attributes.

The basis for Centripetal’s appeal was largely that the board had erred in construing its “packet flow” because it had misconstrued “packet flow entry.” The court found that Centripetal’s own briefing had placed the term “packet flow entry” at issue, and that the company certainly had adequate notice of the issue sufficient to satisfy due process standards. Additionally, evidence indicated that the Board had based its ruling on Centripetal specifically being asked about “packet flow entry” and failing to satisfy the Judge to construe “packet flow” over “packet flow entry.” Additionally, the language of the patent claims themselves indicated a lack of error in construction of the term “packet flow entry.”

Finally, the court found that the board’s determinations on obviousness were supported by substantial evidence. The court affirmed that either the Sourcefire product or the combination of Sourcefire’s log and Macaulay’s reputation score for various attributes would render a finding obviousness on the 18 claims on which the Board had so ruled.

In regard to the two other claims, the court found that the Board had erred in construing Sourcefire’s teachings that rendered the claims obvious. In essence, the court held that findings that Sourcefire had failed to disclose an “existing flow log entry” were not supported by substantial evidence. The Board had failed to note that such logs were updated “on the fly.” Additionally, as Sourcefire would (on refresh) update its flow log entry, then it by necessity must already have a flow log entry.

Accordingly, the court affirmed the Board’s ruling on 18 claims as obvious and reversed the non-obvious ruling on the two other claims from the 917 patent. No costs were awarded.

The Case is No. 24-1406.

Judge: Wallach, E.

Attorneys: Jeffrey B. Wall (Sullivan & Cromwell LLP) for Centripetal Networks, LLC. Gerard M. Donovan (Reed Smith LLP) for Keysight Technologies, Inc.

Companies: Centripetal Networks, LLC; Keysight Technologies, Inc.

Cases: Patent FedCirNews