IP Law Daily, Fed. Cir.: PTAB ‘hardware buffer’ claim construction upheld in Intel, Qualcomm dispute, (Jan 24, 2025)

By Jonathan Anderson

Under the broadest-reasonable-interpretation standard, Qualcomm did not persuasively show that the Board majority’s claim construction was unreasonable.

The U.S. Court of Appeals for the Federal Circuit has affirmed the Patent Trial and Appeal Board’s (PTAB) claim construction of “hardware buffer” in three inter partes review (IPR) proceedings involving a patent owned by Qualcomm and challenged by Intel after a prior remand. In so doing, the court affirmed PTAB’s resulting unpatentability determinations. Noting the significance of the prosecution history, the court held that the case is governed by the broadest-reasonable-interpretation standard and that Qualcomm did not persuasively show the Board majority’s claim construction was unreasonable (Qualcomm Inc. v. Intel Corp., No. 23-1710 (Fed. Cir. Jan. 24, 2025)).

Background. On remand following the court’s decision in Intel Corp. v. Qualcomm Inc., 21 F.4th 801 (Fed. Cir. 2021), a majority of the PTAB panel determined that claims 1–9 and 12 of U.S. Patent No. 8,838,949 (the ’949 patent) were unpatentable for obviousness. Intel Corp. v. Qualcomm Inc., No. IPR2018-01334, 2023 WL 2588220, at *1 (PTAB Mar. 21, 2023). The ’949 patent relates to techniques for generating a power tracking supply voltage for a circuit that processes multiple radio frequency signals simultaneously, using one power amplifier and one power tracking supply generator.

The dispute centers on an issue of claim construction, namely the meaning of “hardware buffer.” On remand from the 2021 decision, the Board majority changed its earlier construction, which excluded “a temporary buffer” from the scope of “hardware buffer,” and on that basis rejected Intel’s unpatentability challenges, to a broader construction, under which a “hardware buffer” is “not limited to a ‘permanent’ buffer.” Based on the new construction, the Board held all challenged claims unpatentable. Qualcomm challenged the Board’s new construction.

Arguments. The parties accepted that a buffer generally is a set of memory cells and accompanying connection lines characterized by its function of serving as a waystation for data being moved from one place to another. The parties disagreed about what is required for the buffer to be a “hardware buffer.”

Intel argued, and the Board majority agreed, that a buffer is a hardware buffer in the ’949 patent if the memory cells used by the buffer are “physically separate” from the memory cells into which the software is loaded and from which the processor executes it. Intel argued that this separation exists even if the cells for buffering use are allocated to that function only when the power is turned on (or runtime) and only for that power-on session.

Qualcomm advanced a narrower view, accepted by the Board before the court’s 2021 decision and by the dissenting administrative patent judge on remand. In that view, a buffer is a hardware buffer only if its memory cells are never used for system memory, rather than assigned to be used for that function (allocated) upon the turning on of power (or runtime).

Not a term of art. Neither party suggested that “hardware buffer” is a term of art with an established meaning in the relevant area. Further, the court found that neither party provided an illuminating or persuasive explanation on its position on the issue of whether “hardware” is superfluous. The court said that neither party delved beneath the terminology of “buffer” and “memory” in their functional meaning to describe concretely the potential makeup and configuration of the physical components and steps used to perform the functions.

Specification. The court found the specification unhelpful. The parties’ uses of “hardware buffer” were not illuminating, while use of the term “allocate” offered no persuasive clarification. The specification’s use of “temporary” or “temporary buffer” provided Qualcomm with some support, but it was not clear or especially strong, according to the court. Further, the specification did not explain how only a hardware buffer under Qualcomm’s proposed construction, in contrast to the broader class of buffers covered by Intel’s proposed construction, would serve the efficiency goals that the specification attributes to the invention.

Prosecution history. The court found the prosecution history illuminating. The Patent Office first rejected the patent as anticipated by Intel’s principal prior-art reference (Svensson, U.S. Patent No. 7,356,680). In doing so, the examiner mapped the claim phrase “hardware buffer” onto the intermediate storage area of Svensson, the same component of the same prior art Intel relied on as teaching the hardware buffer limitation in its obviousness challenge to the patent. Qualcomm argued that Svensson’s intermediate storage area did not meet the hardware buffer limitation, but when Qualcomm responded to the examiner’s initial rejection, it did not expressly or implicitly challenge the examiner’s characterization of the intermediate storage area as a hardware buffer. Instead, Qualcomm modified the claims to make clear that the process its buffer performed was different from that of Svensson’s intermediate storage area. The court found it significant that Qualcomm did not assert the Svensson intermediate storage area, undisputedly allocated at runtime, was outside its claimed “hardware buffer.”

Applicable standard. The Board said it did not need to decide which party had the better reading of “hardware buffer.” The case is governed by the broadest-reasonable-interpretation standard, which recognizes the distinctive duty of applicants or patentees to respond to uncertainty of scope by making clarifying changes. As such, the Board concluded that Qualcomm did not persuasively show the Board majority’s current claim construction as unreasonable.

The Case is Nos. 20-1589, 20-1590, 20-1591, 20-1592, 20-1593, 20-1594.

Judge: Taranto, R.

Attorneys: Jennifer L. Swize (Jones Day) for Qualcomm Inc. Thomas Saunders (Wilmer Cutler Pickering Hale and Dorr LLP) for Intel Corp.

Companies: Qualcomm Inc.; Intel Corp.

Cases: Patent TechnologyInternet FedCirNews USPTO