IP Law Daily, PATENT—Fed. Cir.: Invalidity of G+ Communications’ 5G wireless network technology patent affirmed on appeal, (Jul 31, 2026)

By Carolin Dennis, B.Sc., LL.B., LL.M.

The PTAB did not err in invalidating the 5G wireless network technology patent in light of the cited prior art.

In a non-precedential disposition, the U.S. Court of Appeals for the Federal Circuit rejected the patent owner’s arguments and upheld the final written decision of the Patent Trial and Appeal Board (PTAB) invalidating a patent covering standard-essential 5G wireless network technology. The Federal Circuit found that the PTAB’s final written decision did not violate the Administrative Procedure Act (APA) and substantial evidence supported the PTAB’s challenged findings (G+ Communications, LLC v. Samsung Electronics Co., Ltd., No. 24-2048 (Fed. Cir. Jul. 30, 2026)).

Background. G+ Communications, LLC (G+) owns the U.S. Patent No. 10,736,130 (’130 patent) that claims a method and device for coding uplink signal transmission applicable to 5G mobile communications systems. Samsung Electronics Co., Ltd. (Samsung) filed a petition for inter partes review (IPR) challenging claims 1–5, 7–9, 14, and 20 of the ’130 patent. The PTAB found that U.S. Patent No. 10,615,925 (Kwak) anticipated all challenged claims. The PTAB relied upon Kwak’s Figures 43(b) and 44 as disclosing limitation 1d. G+ timely appealed from the PTAB’s final written decision determining that claims 1–5, 7–9, 14, and 20 of the ’130 patent are unpatentable. The issues G+ presented on appeal are: whether the PTAB violated the APA by relying on an argument that G+ supposedly did not have adequate notice of or an opportunity to respond to; and whether substantial evidence supports the PTAB’s finding that Kwak discloses limitation 1d of the ’130 patent.

APA violation. G+ challenged the PTAB’s reasoning that “Figure 44 ‘may’ be a comb structure but is not necessarily one,” and asserted that Samsung raised this argument for the first time at the oral hearing. G+ contended that the following statements at the oral hearing, by Samsung’s attorney constituted a new argument: “So, they start with saying figure 38 shows a comb structure. I don’t disagree with that. Figure 38 does show a comb structure. But then they say, well, 43 must use a comb structure. When Kwak says, at the bottom of slide 18, for figure 43, may use a comb structure. Then the next, go to figure 44’s description, which again says it may use the structure of figure 44, but then G+ says—sorry, of 43, but G+ says, no, 44 must use the structure of 43, which must be a comb structure. There’s a lot of possibilities that are turned into absolutes by G+ to make this argument.” However, the Federal Circuit found that the “comb structure” issue was initially raised by G+, and the “may” language is found in Kwak itself. Further, G+’s briefing before the PTAB referenced the same portions of Kwak cited by the PTAB in its decision. Additionally, Samsung’s argument at the oral hearing was consistent with its position over the course of the IPR: that Kwak did not—as G+ averred—require that Figure 44 be a comb structure.

In addition, the Federal Circuit found it is implausible to conclude that based on the “may” language, the PTAB rejected G+’s comb structure arguments without substantive analysis. The PTAB’s reference to the “may” language in Kwak was also just one piece of the PTAB’s discussion—three sentences in a roughly four-page discussion of the relevant figures and limitations. Thus, the Federal Circuit determined that the PTAB’s final written decision did not violate the APA.

Substantial-evidence challenges. G+’s first argument was that substantial evidence did not support the PTAB’s finding that Figure 44 does not necessarily include a comb structure even though the PTAB found that other limitations introduced with “may” language are disclosed in Kwak. G+ contended that it was entitled to demand that the “may” language be interpreted consistently across the specification, implying that “may” should be read to exclude or include, but not both. The Federal Circuit found G+’s argument on this point unavailing. However, the Federal Circuit noted that Samsung correctly pointed out that, “a prior art reference anticipates a claim even if it does so only in some modes of operation.”

G+’s second argument was that substantial evidence did not support the PTAB’s finding that Kwak discloses limitation 1d of the ’130 patent. The Federal Circuit found that the PTAB set forth both parties’ arguments and explained that Samsung’s were persuasive. It found that Samsung correctly noted that nothing in Kwak established Figure 44 as a comb structure. The PTAB also credited Samsung’s expert’s testimony explaining that Figure 44 of Kwak lacked shading that distinguishes it from embodiments presented in other figures using shading to indicate the presence of certain regions necessary for comb structures. The PTAB thus properly concluded that Kwak discloses limitation 1d. Therefore, the Federal Circuit concluded that substantial evidence supported the PTAB’s challenged findings.

Accordingly, the PTAB’s decision determining that claims 1–5, 7–9, 14, and 20 of the ’130 patent are unpatentable was affirmed.

The Case is No. 24-2048.

Judge: Prost, S.

Attorneys: Peter Lambrianakos (Fabricant LLP) for G+ Communications, LLC. Naveen Modi (Paul Hastings LLP) for Samsung Electronics Co., Ltd.

Companies: G+ Communications, LLC; Samsung Electronics Co., Ltd.

Cases: Patent FedCirNews