Fresh From the Bench: Latest Precedential Patent Cases
CASE OF THE WEEK
Sisvel International S.A. v. Sierra Wireless, Inc., Appeal Nos. 2022-1493, -1547 (Fed. Cir. Oct. 6, 2023)
Our Case of the Week falls in a series of cases concerning patents that claim a means for performing a particular function using a general-purpose computer. That line of cases has held that the patent must disclose an algorithm that would perform the function. Without that, the claims are deemed indefinite. In an inter partes review, this posed particular concerns, because the PTAB is not authorized to find a patent invalid as indefinite—an inter partes review can only render a patent invalid over prior art. Where the claim is indefinite, it would theoretically not be possible to match the claim element up with prior art.
In the instant case, the patent concerned data transmission technology. Specifically, the patents related to coding data to using data blocks, where redundant data is used, allowing a receiver to detect and correct errors in the transmitted data with greater accuracy. One claim recited “means for detecting,” which the Board construed as a means-plus-function claim, thus requiring disclosure of an algorithm under this line of cases. Sierra identified the patent’s disclosure of two well-known error detection codes as examples of algorithms, and further supplied expert testimony concerning those error detection algorithms. The PTAB, however, found that the patent disclosed insufficient structure—i.e., no corresponding algorithm—and that the testimony could not remedy the insufficient structure disclosed in the specification itself.
ALSO THIS WEEK
Schwendimann v. Neenah, Inc., Appeal Nos. 2022-1333, -1334, -1427, -1432 (Fed. Cir. Oct. 6, 2023)
In this case, the Federal Circuit affirmed inter partes review decisions of the Patent Trial and Appeal Board finding challenged claims of multiple related patents to be obvious over the prior art. Of note, the Court indicated in this case that which reference is the “primary” reference in an obviousness analysis—i.e., the reference to be modified by the teachings of other references—is typically “merely a matter of presentation with no legal significance.” Here, the Court rejected appellant Schwendimann’s argument that the Board was required to articulate a specific rationale for selecting a particular reference as the “primary” reference in its obviousness analysis.
The challenged patents concerned use of multi-layer transfer sheets for transferring printed images onto fabrics; in particular, the use of white or luminescent sheets as a background to improve image quality when transferring dark images onto dark-colored fabrics. The Board found the challenged claims obvious over a combination of prior art referred to as Kronzer and Oez, where Kronzer taught the kind of “peel-last” multi-layer transfer sheets utilized in the claimed invention, and Oez taught a “peel-first” transfer method utilizing a white sheet to improve image quality for dark-colored fabrics. The Federal Circuit found the Board’s “motivation to combine” and “likelihood of success” determinations to be supported by substantial evidence. The Court also found Schwendimann’s “primary reference” argument to have been insufficiently preserved for appeal, but nonetheless addressed it briefly, stating that it “has no basis in our case law,” suggesting that a patent challenger need not analyze extensively which prior art reference a skilled artisan would “start” with to arrive at the claimed invention, or why.
The opinion can be found here.
Editors:
Nika Aldrich, IP Litigation Group Leader, Schwabe, Williamson & Wyatt, P.C.
Jason A. Wrubleski, Shareholder