Context: Proxense LLC is a non-practising entity (NPE) and former operating company focused on enforcing patented biometric authentication and wireless communication technology, which its CEO John Giobbi recently discussed in an exclusive interview with ip fray (April 7, 2026, ip fray article). It previously settled its disputes with Samsung and later with Google (January 24, 2025, ip fray, article), and more recently with Intel (March 24, 2026, ip fray, article). Litigation against Apple (which was initiated in early 2024 (March 23, 2024, ip fray, article) and Microsoft remains stayed. The broader enforcement campaign also includes proceedings involving LG Electronics (January 14, 2025, ip fray article). Prior USPTO decisions upheld core Proxense patents (December 3, 2025, ip fray, article), but tensions arose between USPTO divisions in related proceedings (July 3, 2025, ip fray, article). The present appeal arises from parallel USPTO proceedings in which where the Patent Trial and Appeal Board (PTAB) and the Central Reexamination Unit (CRU) issued conflicting decisions on similar issues of patentability.
What’s new: Proxense last week filed its opening brief before the United States Court of Appeals for the Federal Circuit, arguing that the PTAB violated the Administrative Procedure Act (APA) by staying a parallel ex parte reexamination (EPR) that was about to affirm patentability and then quashing the positive determination of the examiner. The appeal relates to two final written determinations in inter partes reviews (IPRs) of (U.S. Patent No. 8,886,954 (“Biometric personal data key (PDK) authentication”)).
Direct impact: Provided that the Federal Circuit concurs, the unpatentability decisions of the PTAB may be set aside, and the patent claims of Proxense restored. This would greatly bolster the case that Proxense has against Apple and Microsoft in stayed litigation and may put more pressure on the two companies to settle, as Samsung, Google and Intel have already done. The APA-based part of the appeal faces a high standard of review, but a favorable outcome on claim construction, which is reviewed de novo, would also help Proxense.
Wider ramifications: The case could impact how the USPTO handles parallel proceedings. A ruling in Proxense’s favor may limit the PTAB’s ability to sideline reexaminations and require greater consistency across USPTO divisions. It may also affect litigation strategy, particularly in cases where defendants rely on PTAB challenges while patentees pursue parallel reexaminations.
Here is a copy of Proxense’s appellate opening brief:
Proxense’s appeal centers on what it calls a pattern of “outcome control” by the PTAB.
According to the brief, a parallel EPR was already underway at the USPTO’s Central Reexamination Unit (CRU), where an examiner was reviewing closely related claims and the same prior art that Apple and Microsoft relied on in the IPR proceedings.
Stay of EPR at critical stage
During that process, the examiner identified a simple fix: if the claims clearly required that an access message be received by an application, the prior art would no longer invalidate them. Proxense adopted that approach and submitted an amendment.
At that point, just as the reexamination was moving toward confirming patentability, the PTAB stepped in and stayed the proceeding.
Proxense argues that this timing was not coincidental. In its view, the stay prevented the examiner from issuing a reexamination certificate that would have strengthened the patent.
The Board later dismissed the examiner’s withdrawal of prior art rejections as “moot” and not a decision on the merits. Proxense argues this was incorrect, as the examiner had already evaluated the prior art and withdrawn the rejection.
A similar issue arose in a second IPR filed by Microsoft. There too, the CRU reviewed the same references but reached a different conclusion. When Proxense attempted to address those findings at the hearing, the PTAB declined to consider them.
Claim construction dispute over “trusted authority”
Another key issue is how the PTAB interpreted the phrase “a third party that operates a trusted authority”.
The Board defined it as an entity separate from the parties to a transaction, but did not clearly define who those parties are.
Proxense argues that the claims themselves provide that answer: the transaction is the user gaining access to an application. That would make the user and the application the principal parties, leaving any other entity as a third party.
The PTAB disagreed and relied on examples from the patent specification, such as casino machines or retail settings. Proxense responds that these examples only describe where the system is used, not who the parties are.
It further argues that the Board’s interpretation leads to unrealistic results—for example, suggesting that a person could be transacting with themselves when accessing their own device.
After the PTAB decisions, the CRU allowed amended claims clarifying this issue and confirmed that the prior art did not disclose the required “access message” feature.
Constitutional challenge over lack of supervision
Proxense also raises a constitutional argument.
After requesting Director review, the acting director recused herself and delegated authority to a senior Administrative Patent Judge (APJ).
Proxense argues that this violates the Appointments Clause because no principal officer reviewed the decision. It also argues that a related PTAB ruling relying on the same reasoning is affected.
Bigger picture: conflicting USPTO processes
The dispute highlights a structural issue within the USPTO.
As Giobbi put it in the same interview, fighting repeated PTAB challenges can be “genuinely punishing” and “extremely time-consuming” for patent holders (April 7, 2026, ip fray, article).
The America Invents Act (AIA) established the PTAB as a technical, a faster and more technical alternative to district court litigation. The case however demonstrates another issue: what occurs when two sections of the same agency come up with different conclusions on a similar matter.
That question is now before the Federal Circuit.
Proxense is asking the court to vacate the PTAB’s decisions, reverse the findings of unpatentability, and decline to remand, arguing that the USPTO has already confirmed patentability through reexamination.
Apple and Microsoft now get to respond.
Court and Counsel
Court: United States Court of Appeals for the Federal Circuit
Appeal: Consolidated appeals from IPR2024-00233, IPR2024-01334, and IPR2024-00846 (Patent Trial and Appeal Board).
Appellant Proxense LLC is represented by : Hecht Partners LLP’s David L. Hecht, and James A. Zak.
Appellee Apple Inc. is represented by :Finnegan, Henderson, Farabow, Garrett & Dunner LLP’s Erika Arner, Kara Specht, Cory Bell, Safiya Aguilar, and Shawn Chang; and Duane Morris LLP‘s Philip W. Woo, D. Stuart Bartow, Monte T. Squire, and Paul Belnap.
Appellee Microsoft Corporation is represented by: Fish & Richardson P.C.’s W. Karl Renner, Roberto Devoto, and Usman Khan.