Opinions — Wednesday, January 21, 2026

In Ozat USA, LLC v. Ozat 2000(1999) Ltd., the Federal Circuit dismissed the appeal from the Trademark Trial and Appeal Board under Federal Rule of Appellate Procedure 42(b) based on the parties' agreement, with each side bearing its own costs.

In Western Digital Technologies, Inc. v. Longitude Licensing Ltd., the Federal Circuit dismissed the appeal from a Patent Trial and Appeal Board decision in IPR2023-01230 pursuant to Federal Rule of Appellate Procedure 42(b) based on the parties' stipulation. The court ordered that each side bear its own costs and issued the order as mandate on January 21, 2026.

The Federal Circuit affirmed the PTAB's decision sustaining the Examiner's rejection of all sixteen claims of U.S. Patent No. 8,412,488, owned by EcoFactor, Inc., which relates to monitoring HVAC systems to determine operational status. During ex parte reexamination initiated by Google, EcoFactor amended independent claims 1 and 9 to change the comparison from "an inside temperature" versus an estimated rate of change to "an actual rate of change in inside temperature" versus an estimated rate of change. The Board rejected the amended claims on two independent grounds: impermissible claim enlargement under 35 U.S.C. § 305 and obviousness under pre-AIA § 103(a).

The court's analysis turned on whether comparing two rates of change is equivalent to comparing a temperature value with a rate of change for purposes of claim scope. Applying Quantum Corp. v. Rodime and Creo Products v. Presstek, the court held that a system comparing actual and estimated rates would not have infringed the original claim (which required comparing a point-in-time temperature value to an estimated rate), but would infringe the amended claim, thus establishing enlargement. The court rejected EcoFactor's argument that because calculating an actual rate necessarily uses temperature values, the claims were equivalent, emphasizing that the relevant inquiry is what value the system ultimately compares to determine HVAC status, not what inputs feed into that calculation.

The Federal Circuit affirmed a stipulated final judgment of noninfringement in favor of Cisco Systems, Inc. against Lionra Technologies Ltd. concerning U.S. Patent No. 7,623,518. The dispute centered on whether a patent license agreement between Lionra and RPX Corporation—under which Intel was an enumerated licensee—barred Lionra's infringement allegations against Cisco's products containing Intel processors. Because Lionra had not appealed an earlier district court decision (Lionra I) adopting the same contract interpretation, the parties stipulated to noninfringement based on that reasoning.

The court applied de novo review to the Delaware-law contract interpretation, focusing on whether Intel processors in the accused products qualified as "Combined Licensed Product[s]" that satisfied "one or more material elements" of the asserted claims. The court rejected Lionra's argument that the processor must be independently "operable" to perform all the claim-recited functions to constitute a covered "element," holding instead that the plain language of the agreement was satisfied where the accused products incorporated Intel processors, the claims required "a processor," and Lionra itself alleged the Intel processors met that limitation. The covenant-not-to-sue provision further barred Lionra from asserting the licensed patents against Cisco as a "Covered Third Party" with respect to products combining Intel components with other technology.

The Federal Circuit affirmed-in-part and vacated-in-part a jury verdict of non-infringement and invalidity for certain asserted claims of CellTrust Corporation's U.S. Patent Nos. 9,775,012 and 10,778,837, which cover systems and methods for tracking electronic communications. CellTrust appealed the district court's denial of JMOL on infringement and validity, as well as denial of its motion for new trial, primarily challenging a post-trial claim construction that allegedly imported a "directly" limitation into the claims' "sending" requirements and the district court's refusal to give a corroboration jury instruction regarding defendants' expert testimony on obviousness.

The court held that CellTrust forfeited its claim construction argument by failing to request construction of "sending" before trial or object to the jury instructions before the jury retired, following Ecolab and LifeNet Health. Substantial evidence supported the jury's non-infringement verdict under the instructions given, particularly where CellTrust's expert admitted he did not examine source code, could not read code, and did not know how communications were sent after leaving the accused server. On validity, the court found any error in omitting a corroboration instruction was harmless under Eighth Circuit standards because defendants' expert testimony was sufficiently corroborated through circumstantial evidence, other witness testimony, and trial exhibits—including CellTrust's own expert's concessions and documentary evidence regarding the Google prior art at issue. The court vacated only the overbroad judgment language that addressed all claims of the patents rather than just the asserted claims, remanding for correction of this clerical error under Rule 60(a).

The Federal Circuit reversed in part and vacated in part the Board's final written decision in an IPR challenging claims of Smart Mobile's U.S. Patent No. 8,472,936, which relates to dynamically configurable mobile devices. Apple had successfully challenged substantially similar claims in two related patents (the '739 and '501 patents) using the same prior art combination, but the Board found Apple failed to prove obviousness of the '936 patent claims, turning on its construction of "dynamically configurable" to require configuration "without the need for user intervention."

The court's issue preclusion analysis offers a notable framework for defeating serial assertion of materially identical claims across related patents. Applying Ohio Willow Wood and its progeny, the court held that claims need not be textually identical for issue preclusion to apply; rather, the question is whether differences "materially alter the question of invalidity" when assessed on a claim-by-claim basis rather than limitation-by-limitation. The court rejected Smart Mobile's attempt to narrow the "issue" to whether specific references taught specific limitations, holding that the relevant "issue" was the validity of the entire claim where the parties presented nearly identical obviousness theories and claim construction arguments across proceedings. On claim construction, the court upheld the Board's addition of "without user intervention" based on the specification's repeated and consistent characterization of automatic switching, reinforced by prosecution history.