Background
G+ Communications appealed a Patent Trial and Appeal Board final written decision holding claims 1–5, 7–9, 14, and 20 of U.S. Patent No. 10,736,130 unpatentable. The patent concerns coding uplink control signals in 5G mobile communications, including mapping predefined sequences of length N to N subcarriers.
Samsung’s inter partes review petition asserted that U.S. Patent No. 10,615,925, known as Kwak, anticipated the challenged claims. G+ argued that Kwak’s Figure 44 necessarily used a “comb structure” that reserved every other subcarrier for a demodulation reference signal, leaving only six subcarriers for a sequence of length twelve and therefore failing to disclose the claimed mapping. The Board rejected that argument, finding that Kwak did not establish Figure 44 as necessarily using a comb structure.
The Court’s Holding
The Federal Circuit affirmed. It rejected G+’s argument that the Board violated the Administrative Procedure Act by relying on a new argument first presented by Samsung at the oral hearing. G+ had introduced the comb-structure issue, the relevant “may” language appeared in Kwak itself, G+ had cited the same portions of Kwak before the Board, and Samsung’s hearing presentation was consistent with its earlier position that Figure 44 did not require a comb structure. The court characterized Samsung’s presentation as a permissible elaboration on an issue already raised.
The court also held that substantial evidence supported the Board’s anticipation findings. A prior-art reference can anticipate when some modes of operation embody the claimed method, even if others do not. The Board reasonably credited Samsung’s expert testimony that Figure 44 lacked shading used in other Kwak figures to identify regions associated with comb structures. That evidence supported the finding that Kwak disclosed the limitation requiring an N-length sequence mapped to N subcarriers.
Key Takeaways
- An IPR party may elaborate at oral argument on an issue and position already presented without necessarily introducing an impermissible new argument under the APA.
- A prior-art reference may anticipate a claim when only some disclosed modes of operation embody the claimed method.
- Detailed expert testimony explaining how a prior-art figure discloses a claim limitation can constitute substantial evidence supporting anticipation.
Why It Matters
The nonprecedential decision illustrates the distinction between a genuinely new theory raised at an IPR hearing and further development of an existing argument. When the disputed issue, relevant specification language, and parties’ positions were already before the Board, additional hearing argument may not create a notice violation.
The decision also reinforces that optional language in a prior-art reference does not defeat anticipation merely because the disclosed feature is not present in every embodiment. The relevant question is whether the reference discloses a mode that contains each claim limitation.