DCT

3:23-cv-00811

Shoals Tech Group LLC v. Hikam America Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:23-cv-00811, S.D. Cal., 05/04/2023
  • Venue Allegations: Venue is alleged to be proper in the Southern District of California because Defendant Hikam America, Inc. resides in the district, and all defendants have allegedly transacted business and committed acts of infringement there. For the foreign defendants, venue is alleged to be proper in any U.S. judicial district.
  • Core Dispute: Plaintiff alleges that Defendants' solar wire harnesses and replacement in-line fuse kits infringe a patent related to environmentally sealed, overmolded in-line fuse assemblies for solar panel installations.
  • Technical Context: The technology concerns electrical balance of system (EBOS) components used in large-scale photovoltaic arrays, which are designed to improve system reliability and efficiency by localizing circuit protection.
  • Key Procedural History: The complaint alleges that Plaintiff has satisfied the statutory marking requirements of 35 U.S.C. § 287. No other prior litigation, licensing, or post-grant proceedings are mentioned.

Case Timeline

Date Event
2013-06-03 ’739 Patent Priority Date
2020-02-04 ’739 Patent Issue Date
2023-05-04 Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 10,553,739 - "Photovoltaic In Line Fuse Connector Assembly Having An Integral Fuse," issued February 4, 2020

The Invention Explained

  • Problem Addressed: In conventional large-scale solar installations, multiple solar panels are wired into an array that is protected by a single, centralized fuse in a combiner box. A malfunction in just one panel can trip this fuse, shutting down the entire array and "needlessly reduc[ing] the overall efficiency of the solar installation" (’739 Patent, col. 1:31-36).
  • The Patented Solution: The invention moves the circuit protection from the centralized combiner box directly into the wiring harness by creating an in-line fuse assembly for each solar panel. This assembly features an integrated fuse that is environmentally sealed by a "double molded" process, consisting of a first "undermold" layer and a second "overmold" layer to provide "electrical insulation, protection and strain relief" (’739 Patent, col. 2:53-54). This design isolates a fault to a single panel, allowing the rest of the array to continue operating normally (’739 Patent, col. 2:60-63; Fig. 4).
  • Technical Importance: This decentralized approach to circuit protection allows for more simplified solar field architectures and improves the overall energy output and reliability of the installation by preventing single-panel faults from disabling entire panel strings (Compl. ¶23; ’739 Patent, col. 2:58-63).

Key Claims at a Glance

  • The complaint asserts independent claims 1, 10, and 15 (Compl. ¶35).
  • Independent Claim 1, an assembly claim, recites the following essential elements:
    • A photovoltaic fuse with a solid outer surface defining an outline.
    • An undermold that surrounds and seals the fuse, with its outer surface "substantially parallel" to the fuse's outline.
    • An overmold that surrounds the undermold, with its outline "substantially parallel" to the undermold's outline.
    • The undermold and overmold are each constructed of a "single unit" and of "dissimilar materials."
    • A first photovoltaic connector engaged with the first end of the fuse.

III. The Accused Instrumentality

Product Identification

  • The Hikam Wire Harness and the Hikam Replacement In-Line Fuse (RILF) Kit (collectively, "Accused Products") (Compl. ¶27).

Functionality and Market Context

  • The Accused Products are described as wire harnesses and in-line fuse kits intended for use in solar panel installations (Compl. ¶27). The complaint alleges that the products include an "in-line fuse structure with an outer surface, a first end, second end, middle section, overmold and undermold, as well as a photovoltaic connector" (Compl. ¶30). The complaint includes a photograph depicting a cutaway of an accused device, labeling the internal fuse and the surrounding "undermold" and "overmold" layers (Compl. p. 9). Plaintiff cites Defendants' marketing materials, which allegedly tout "three decades of experience as a turnkey manufacturer of wiring harnesses, and 6 years of specialized experience with Solar Harness Assemblies" (Compl. ¶27).

IV. Analysis of Infringement Allegations

The complaint provides narrative allegations of infringement for claims 1, 10, and 15, and states that claim charts are attached as Exhibits 2 and 3 (Compl. ¶¶38, 42). As the exhibits were not provided, the following summary is based on the complaint's narrative breakdown of claim 1.

’739 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a. A photovoltaic fuse having a solid outer surface including a first end, a second end and a middle section there between, said solid outer surface defining an outline; The Accused Products include a photovoltaic fuse with a solid outer surface, a first end, a second end, and a middle section, as shown in a labeled photograph of the device. ¶43a; p. 9 col. 4:28-32
b. An undermold surrounding and sealing said fuse, said undermold defining an outer surface outline, wherein the outer surface outline of said undermold is substantially parallel relative to the outline of said solid outer surface; The Accused Products allegedly have an undermold that surrounds and seals the fuse, defining an outer surface that is substantially parallel to the fuse's outline. The complaint provides a cutaway visual labeling the "undermold" layer. ¶43b; p. 9 col. 4:33-38
c. An overmold defining an outline and surrounding said undermold, said undermold and said overmold each constructed of a single unit and each constructed of dissimilar materials, wherein the outline of said overmold is substantially parallel relative to the outline of said undermold; The Accused Products allegedly have an overmold surrounding the undermold, with the undermold and overmold each being a single unit of dissimilar materials. A cutaway visual labels the "overmold" layer. ¶43c; p. 9 col. 4:39-44
d. A first photovoltaic connector engaged with said first end, wherein said assembly provides electrical insulation. The Accused Products allegedly include a first photovoltaic connector engaged with the fuse's first end. A product photograph labels the "first photovoltaic connector." ¶43d; p. 9 col. 4:45-48
  • Identified Points of Contention:
    • Scope Questions: A central question may be the proper construction of "dissimilar materials." The complaint alleges this element is met but does not specify the materials used in the accused products (Compl. ¶43c). The dispute may focus on what degree of chemical or physical difference is required to qualify as "dissimilar" in the context of the patent.
    • Technical Questions: The claims require the outlines of the molded layers to be "substantially parallel" to the underlying structures (’739 Patent, col. 4:36-38, 43-44). The question will be whether the geometry of the Accused Products, as depicted in the complaint's visuals (Compl. p. 9) and as they exist in fact, meets this geometric limitation, which could be a point of significant factual dispute.

V. Key Claim Terms for Construction

  • The Term: "said undermold and said overmold each constructed of a single unit and each constructed of dissimilar materials" (’739 Patent, col. 4:40-42).
  • Context and Importance: This limitation is critical as it defines the core structural and material characteristics of the patented "double molded" seal. Practitioners may focus on this term because infringement will depend on whether the accused two-layer structure is made from materials that are legally "dissimilar" and whether each layer constitutes a "single unit."
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification provides examples of materials ("modified polyphenylene ether plastic" for the undermold and "a thermoplastic elastomer" for the overmold) but does not state these are the only possibilities, which may support a broader interpretation that any two different moldable plastics or polymers qualify as "dissimilar" (’739 Patent, col. 3:15-20).
    • Evidence for a Narrower Interpretation: A party could argue that the specific examples teach a functional distinction—a rigid structural undermold and a flexible, sealing overmold—and that "dissimilar materials" should be construed to require this functional difference. Further, "single unit" could be interpreted narrowly to mean a seamless, monolithic structure formed in a single molding step, potentially excluding assemblies of multiple pieces.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendants induce infringement by "actively and knowingly inducing others to make, use, sell, offer for sale, or import" the Accused Products (Compl. ¶36). It also alleges contributory infringement by "actively encouraging, promoting, distributing, providing instructions for, and supporting the assembly and use" of the products (Compl. ¶37).
  • Willful Infringement: The willfulness allegation is based on notice of infringement provided by the filing of the complaint itself (Compl. ¶46).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A core issue will be one of claim construction and material science: can the phrase "dissimilar materials" be construed broadly enough to read on the specific materials used in the accused Hikam products, and what level of evidence will be required to prove the materials are, in fact, different?
  • A key evidentiary question will be one of geometric and structural proof: does the physical construction of the Accused Products meet the "substantially parallel" and "single unit" limitations of the claims? This will likely move beyond the complaint's illustrative photographs and require expert analysis of the physical products to resolve potential factual disputes over their precise geometry and manufacturing method.