Our Patent Case Summaries provide a weekly summary of the precedential patent-related opinions issued by the Court of Appeals for the Federal Circuit and the opinions designated precedential or informative by the Patent Trial and Appeal Board.
AML IP, LLC v. Bath & Body Works Direct, Inc., et al.
No. 2025-1280 (Fed. Cir. (E.D. Tex.) Aug. 28, 2026). Opinion by Prost, joined by Bryson and Reyna.
AML sued several companies for patent infringement. The defendants moved to dismiss for both improper venue and failure to state a claim because the patent claims allegedly were ineligible for patenting under 35 U.S.C. § 101. The district court dismissed on both grounds. AML appealed.
In the appeal, AML did not dispute the merits of the district court’s conclusions as to venue or eligibility. Instead, AML argued that, after the court concluded that venue was improper and dismissed for that reason, the court erred by going further and dismissing for eligibility as well.
The Federal Circuit disagreed with AML and affirmed. The court ruled that the district court had the power to dismiss for failure to state a claim after it concluded that venue was improper. The Federal Circuit explained that venue—unlike subject-matter jurisdiction, for example—is waivable and does not implicate a court’s power to act. AML argued that the district court nonetheless should not have decided the eligibility issue, but the Federal Circuit disagreed and noted that “certain judicial-economy considerations actually favor the district court’s approach of deciding both grounds.”
AML also argued that the district court’s eligibility decision should be vacated because, according to AML, it will not have preclusive effect in future cases. The Federal Circuit, however, “reject[ed] AML’s request for what is essentially an advisory opinion on the preclusive effect that the district court’s judgment (and ours) might have in future cases.”
T-Mobile US, Inc., et al. v. KAIFI LLC
No. 2025-1006 (Fed. Cir. (E.D. Tex.) Aug. 28, 2028). Opinion by Chen, joined by Taranto and Schall.
KAIFI sued T-Mobile for patent infringement, and they settled the case. At the time of settlement an ex parte reexamination (EPR) proceeding, which T-Mobile had initiated, remained ongoing. The parties’ settlement agreement included a provision where T-Mobile agreed to make an additional payment to KAIFI at the conclusion of the EPR “if any Asserted Claim survives the EPR.”
The EPR concluded with the Patent Office confirming the patentability of multiple asserted claims without amendment. T-Mobile then sought a declaratory judgment that no asserted claims had “survived” the EPR and that therefore it had not breached the settlement agreement by refusing to make the additional payment. KAIFI counterclaimed for breach of contract. The district court ruled in KAIFI’s favor and ordered T-Mobile to make the additional payment, and T-Mobile appealed.
In the appeal, both parties contended that the Federal Circuit had appellate jurisdiction over this case concerning the interpretation of the settlement-agreement phrase “survives the EPR.” But the Federal Circuit disagreed and transferred the appeal to the Fifth Circuit.
As the Federal Circuit explained, its jurisdiction is grounded in 28 U.S.C. § 1295(a)(1), which the Supreme Court has interpreted to mean that the jurisdiction extends “only to those cases in which a well-pleaded complaint establishes either [1] that federal patent law creates the cause of action or [2] that the plaintiff’s right to relief necessarily depends on resolution of a substantial question of federal patent law, in that patent law is a necessary element of one of the well-pleaded claims.”
In assessing whether a case falls within that latter “special and small category” of cases, the Federal Circuit applies the four-part Gunn test. Under Gunn, a state-law claim arises under federal law when a federal issue is “(1) necessarily raised, (2) actually disputed, (3) substantial, and (4) capable of resolution in federal court without disrupting the federal-state balance approved by Congress.”
The Federal Circuit focused on the first and third Gunn requirements and ruled that neither is satisfied. Beginning with whether a federal issue is “necessarily raised,” the court focused on KAIFI’s breach of contract claim. The court failed to see “how determining whether any of the asserted patent claims ‘survived the EPR’ necessarily raises a patent law issue.” For example, the Federal Circuit said its use of the term in its decisions never suggested it was “assigning a particularized patent-law meaning to ‘survives.’”
For the third Gunn factor, the Federal Circuit ruled that none of the pertinent factors indicated substantiality. The court explained that there is no dispositive federal law issue, resolution of the issue will not control “numerous other cases,” and the government has no direct interest in this contract dispute between private parties.
For these reasons, the court ruled that it lacks appellate jurisdiction over the case.
Ex parte Chowdhury
Appeal No. 2025-002261 (PTAB Feb. 5, 2026) (designated informative on Aug. 25, 2026). Opinion by Flax, joined by Katz and Hardman.
A patent Examiner rejected certain claims of a pending application related to microRNAs (MiRNAs) and their use in quantifying radiation exposure. The Examiner rejected the claims as reciting improper Markush groupings—that is, improper groupings of alternatively useable members of a class.
In rejecting the claims, the Examiner determined that the recited lists of miRNAs “do not share a single structural similarity, as each miRNA has a different chemical structure in that it consists of a different nucleotide sequence.” The Examiner also explained that “the recited miRNAs do not belong to a chemical or art-recognized class because there is no expectation from the knowledge in the prior art that the miRNAs behave in the same manner and can be substituted for one another with the same intended result achieved.”
The Patent Trial and Appeal Board reversed the Examiner’s rejection. The Board explained that “if a recited Markush group lists a set of things that the inventor describes as a subgenus, and those things are described in the specification as useful for the function of the invention because of their similarities, then their inclusion in a Markush group is not improper.”
The Board ruled that the Examiner misinterpreted or overlooked the claimed invention, as “individual miRNA functionality is not contemplated in the context of the claimed invention.” The Board explained that “the listed miRNA species need only be quantifiable to achieve the invention’s purpose and this function is not disputed here.” The Board thus concluded that “the recited miRNAs are interchangeable in the context of the invention” and accordingly reversed the Examiner’s finding that the Markush groups were improper.