Littelfuse, Inc. v. Mersen USA EP Corp., Appeal No. 2021-2013 (Fed. Cir. Apr. 4, 2022)
Our Case of the Week focuses on the issue of claim construction, and, more specifically, the doctrine of claim differentiation.
The patent at issue was directed to a “fuse end cap for providing an electrical connection between a fuse and an electrical conductor.” The patent described three embodiments of end caps: a “machined end cap,” a “stamped end cap,” and an “assembled end cap.” The first two may be made from a single piece of material that is either machined or otherwise formed into the end cap. The last is made from two separate pieces of material.
Claim 1 of the patent recited an end cap with a “mounting cuff,” a “terminal,” and a “fastening stem.” Claims 8 and 9 recited, respectively, “[t]he fuse end cap of claim 1, wherein the mounting cuff and the terminal are [machined/stamped] from a single, contiguous piece of conductive material.”
During prosecution, the examiner issued a restriction requirement, noting that the three types of end cap were three different species. Littelfuse responded by electing to prosecute the species corresponding to the “assembled end cap” embodiment. The examiner then withdrew dependent claims 8 and 9, which both corresponded with machined or stamped end cap embodiments. But after further prosecution, the examiner allowed those claims back in based on Patent Office procedures. This was because claim 1, a generic claim, was allowed, and the dependent claims were compatible with allowed claim 1.
During litigation, the district court construed the term “fastening stem” to mean a “stem that attaches or joins other components.” Thus, the court’s construction inherently narrowed the scope of the claim to multi-component end caps, like the assembled end cap embodiment. The district court’s construction precluded a “machined end cap” or a “stamped end cap” formed from a single piece of material. Following a stipulation of summary judgment, Littelfuse appealed.
The Federal Circuit reversed. Its critical holding is succinct:
By definition, an independent claim is broader than a claim that depends from it, so if a dependent claim reads on a particular embodiment of the claimed invention, the corresponding independent claim must cover that embodiment as well. . . . Otherwise, the dependent claims would have no scope and thus be meaningless. A claim construction that leads to that result is generally disfavored. . . . Accordingly, the recitation of a single-piece apparatus in claims 8, 9, 19, and 20 is persuasive evidence that claims 1 and 10 also cover a single-piece apparatus.
The Court noted that “the presumption of differentiation in claim scope is not a hard and fast rule,” and that “any presumption created by the doctrine of claim differentiation ‘will be overcome by a contrary construction dictated by the written description or prosecution history.’” However, the specification here supported a broader construction, and the prosecution history did not overcome the presumption.
The Court also noticed that a “fastening stem” could still be present in a single-piece apparatus, given its structure as disclosed and claimed in the patent. The Court went on to confirm that a “fastening stem” must both include a “stem” and must “fasten.”
The case was reversed and remanded to the district court to adopt a claim construction consistent with the court’s guidance, but not precluding a single-component end cap.
The opinion can be found here.
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Roche Diagnostics Corporation v. Meso Scale Diagnostics, LLC, Appeal Nos. 2021-1609, -1633 (Fed. Cir. April 8, 2022)
In an appeal from a district court decision, the Court addressed a licensing dispute in a lengthy opinion covering numerous legal and factual issues. Roche filed for declaratory judgement for non-infringement of patents, the rights to which Meso claimed to hold via an exclusive license. Meso counterclaimed for infringement. The jury found that Meso held an exclusive license to the asserted patent claims and that Roche directly infringed one claim, induced infringement of three claims, and did so willfully. The district court granted Roche judgement as a matter of law on willfulness, denied Meso’s motions to enhance damages, and granted Roche’s request for a finding of non-infringement on three additional patents, due to their being compulsory counterclaims that Meso failed to bring in its counterclaim. Given insufficient reason to overturn the district court’s finding that the patents-in-suit were within the scope of rights licensed exclusively to Meso, the Federal Circuit affirmed on direct infringement. On induced infringement, the Federal Circuit reversed the district court on both the intent and inducing acts prongs. The Federal Circuit agreed with Roche that, because the intent standard for induced infringement is similar to the intent standard for willfulness and enhanced damages, the same facts that led to JMOL on willfulness and denial of enhanced damages should have led to JMOL on induced infringement. The Federal Circuit also agreed that, although the induced infringing acts occurred during the six-year window prior to suit, because the acts that induced the infringing acts occurred before the six-year window, the induced acts prong was not met. Because the Federal Circuit reversed on induced infringement, it vacated for a new trial on damages. The Federal Circuit also vacated the non-infringement finding as to the three additional patents, agreeing with Meso that a counterclaim that is compulsory but not brought is barred in subsequent actions, but not in a present action. The Federal Circuit did not reach the question of whether Roche’s complaint was too generic to trigger the compulsory counterclaim rule, saving that determination for any district court called to hear a subsequent infringement action by Meso concerning the additional patents. In dissent, Judge Newman argued that Roche cannot infringe patents it owns, and, detailing the complicated history of the patents-in-suit, that Roche had owned the patents since 2007.
The opinion can be found here.