Deanne Maynard of Morrison & Foerster.

Nevro Corp.'s patents on spinal stimulating implants got a jolt Thursday from the U.S. Court of Appeals for the Federal Circuit.

The appellate court reversed a ruling from U.S. District Judge Vince Chhabria that had held 12 claims from four of Nevro's patents invalid as indefinite.

Nevro v. Boston Scientific may not have an immediate impact on the Northern District of California litigation over pain treatment techniques, because Boston Scientific has already opted out of the high-frequency stimulation market that Nevro occupies in the U.S. But it ought to boost Nevro's patent litigation against other competitors such as Nalu Medical Inc.

"We are confident that the claims upheld by the appellate court will protect our exclusivity in high frequency, paresthesia-free SCS therapy," Kashif Rashid, general counsel for Redwood City-based Nevro, said in a written statement.

The decision hands a win to a Morrison & Foerster team that includes partners Michael Jacobs and Deanne Maynard, and adds some gloss to the U.S. Supreme Court's 2014 indefiniteness ruling Nautilus v. Biosig.

The claims describe an electric signal generator that is "configured to" generate a therapy signal within certain parameters and that will reduce pain without generating paresthesia—a feeling of numbness or tingling associated with prior art stimulation devices.

Chhabria had ruled that because each patient will react differently to the stimulation, a skilled artisan would not be able to identify the boundaries of the patent with reasonable certainty. He also found the "configured to" language indefinite, because it could be read to mean either that the signal generator had the capacity to generate signals or that it had actually been programmed to generate signals.

The Federal Circuit disagreed on both counts Thursday. "The test for indefiniteness is not whether infringement of the claim must be determined on a case-by-case basis," Judge Kimberly Moore wrote for a unanimous panel. "Instead, it is simply whether a claim 'inform[s] those skilled in the art about the scope of the invention with reasonable certainty,'" she wrote, quoting Nautilus.

The patent claim specifications provide hard examples such as "therapeutic signals at a frequency of from about 3 kHz to about 10 kHz" and amplitudes ranging "from about 1 mA to about 4 mA." There was enough in the specification for a person of ordinary skill to determine whether a system, device or method is within the claim scope, Moore wrote. "That a given signal will eliminate paresthesia in some patients, but not others, does not render the claims indefinite," she wrote.

As for "configured to generate," the context of the patent makes clear that it means "programmed to generate," Moore wrote. "The test is not merely whether a claim is susceptible to differing interpretations," she wrote. "Such a test would render nearly every claim term indefinite so long as a party could manufacture a plausible construction."

Judges Richard Taranto and Raymond Chen concurred.

Maynard argued the appeal for Nevro. Arnold & Porter Kaye Scholer partner Matthew Wolf argued for Boston Scientific.

Nevro didn't get quite everything it wanted. The company had asked the Federal Circuit to construe "configured to" as "designed to." Moore wrote that "programmed to" is more consistent with the specification and statements Nevro made during patent prosecution.