Shoals Tech Group LLC v. Voltage LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Shoals Technologies Group, LLC (Tennessee)
  • Defendant: Voltage, LLC (North Carolina) and Ningbo Voltage Smart Production Co. (People's Republic of China)
  • Plaintiff’s Counsel: Troutman Pepper Locke LLP
• Case Identification: 1:25-cv-00026, M.D.N.C., 10/10/2025
• Venue Allegations: Venue is alleged to be proper in the Middle District of North Carolina because Defendant Voltage, LLC resides and maintains physical offices in the district, and both defendants have allegedly transacted business and committed acts of infringement in the district. For Defendant Ningbo Voltage, a Chinese company, venue is asserted to be proper in any judicial district.
• Core Dispute: Plaintiff alleges that Defendants’ solar panel connector systems, known as the Voltage LYNX Trunk Bus, infringe three U.S. patents related to lead assemblies for solar panel installations.
• Technical Context: The technology at issue involves electrical balance of systems (EBOS) solutions, which constitute the wiring infrastructure used to connect solar panels to inverters, a critical component for reducing the cost and complexity of large-scale solar energy projects.
• Key Procedural History: The complaint discloses a concurrent, separate proceeding between the parties before the U.S. International Trade Commission (ITC) involving the ’375 and ’376 patents. Plaintiff alleges that Defendants used confidential business information produced by Plaintiff under a protective order in the ITC case to create "alternative designs" that also infringe the asserted patents. The complaint also alleges Defendants had pre-suit knowledge of the patent family by citing related patents in an Information Disclosure Statement filed at the U.S. Patent and Trademark Office.

Case Timeline

Date	Event
2014-09-09	Priority Date for ’375, ’376, and ’295 Patents
2024-06-18	Issue Date for U.S. Patent No. 12,015,375
2024-06-18	Issue Date for U.S. Patent No. 12,015,376
2024-11-01	Voltage President's public statement (approximate date)
2025-02-20	Protective Order entered in related ITC Proceeding
2025-09-02	Issue Date for U.S. Patent No. 12,407,295
2025-10-10	Complaint Filing Date

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

U.S. Patent No. 12,015,375 - "Lead Assembly for Connecting Solar Panel Arrays to Inverter"

• Patent Identification: U.S. Patent No. 12,015,375, "Lead Assembly for Connecting Solar Panel Arrays to Inverter," issued June 18, 2024 (’375 Patent).

The Invention Explained

• Problem Addressed: The patent’s background section describes conventional solar power installations that require numerous individual connections from solar arrays to a central "combiner box." These boxes are described as "clumsy, prone to damage and malfunctioning," and require extensive labor to install and maintain, adding significant cost and potential points of failure to a solar project (’375 Patent, col. 1:47-57).
• The Patented Solution: The invention is a pre-fabricated lead assembly that eliminates the need for a combiner box. It features a main "feeder cable" with one or more integrated "drop lines." Each drop line connects to a solar array, and the electrical connection point (nexus) between the drop line and the feeder cable is encapsulated in a durable, protective mold. This allows the power from multiple solar arrays to be aggregated directly along the feeder cable, which then connects to an inverter, streamlining the entire wiring process (’375 Patent, Abstract; col. 2:1-11). The use of injection molding to create an undermold and overmold at the joint results in a "profoundly durable" and weather-resistant assembly suitable for burial (’375 Patent, col. 6:3-10).
• Technical Importance: This "trunk bus" architecture significantly simplifies the design and construction of solar fields, reducing material costs, labor hours, and potential sources of electrical failure (Compl. ¶21).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶51).
• Claim 1 of the ’375 Patent includes these essential elements:
  • A lead assembly for electrically coupling drop lines to a feeder cable.
  • A joint where a section of the feeder cable and a section of one or more drop lines are electrically coupled at a nexus.
  • A monolithic mold that encapsulates the nexus, the mold having pathways for the feeder cable and drop lines to pass through.
  • The drop lines are configured to receive electrical power from solar panels for combination at the nexus.
  • At the nexus, a portion of the exposed wire of the drop line is parallel to a portion of the exposed wire of the feeder cable.
• The complaint does not explicitly reserve the right to assert dependent claims for this patent.

U.S. Patent No. 12,015,376 - "Lead Assembly for Connecting Solar Panel Arrays to Inverter"

• Patent Identification: U.S. Patent No. 12,015,376, "Lead Assembly for Connecting Solar Panel Arrays to Inverter," issued June 18, 2024 (’376 Patent).

The Invention Explained

• Problem Addressed: As with the related ’375 Patent, this invention aims to solve the technical problem of costly and unreliable combiner boxes in solar installations by providing a more integrated and durable wiring solution (’376 Patent, col. 1:47-57).
• The Patented Solution: The patent describes a lead assembly comprising a feeder cable, first and second drop lines, and one or more mold structures. The drop lines are configured to connect to separate solar arrays. The key feature is the geometric arrangement where the two drop lines are connected to the feeder cable at a sealed, molded interconnection and "extend in opposite directions along a longitudinal axis that is parallel to a longitudinal axis of the feeder cable." This configuration allows a single assembly to service two adjacent arrays or rows of panels, further simplifying field layout and reducing the total amount of wiring required (’376 Patent, Abstract; claim 1).
• Technical Importance: This dual-drop-line configuration enhances installation efficiency by allowing a single component to serve as the collection point for multiple, distinct solar arrays (Compl. ¶21, ¶23).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶61).
• Claim 1 of the ’376 Patent includes these essential elements:
  • A lead assembly with a feeder cable, a first drop line, and a second drop line.
  • Each drop line has a connector for receiving combined electrical power from a solar array.
  • One or more mold structures that substantially seal the electrical interconnection region between the feeder cable and the drop lines.
  • In the interconnection region, the first and second drop lines extend in opposite directions along an axis that is parallel to the longitudinal axis of the feeder cable.
• The complaint does not explicitly reserve the right to assert dependent claims for this patent.

U.S. Patent No. 12,407,295 - "Lead Assembly for Connecting Solar Panel Arrays to Inverter"

• Patent Identification: U.S. Patent No. 12,407,295, "Lead Assembly for Connecting Solar Panel Arrays to Inverter," issued September 2, 2025 (’295 Patent).
• Technology Synopsis: This patent, also in the same family, is directed to a lead assembly system for solar installations that eliminates combiner boxes. It describes a system using first and second feeder cables (e.g., for positive and negative polarity) with multiple drop lines connected at molded joints. The invention specifies structural details of the assembly, including the use of in-line fuses on the drop lines to provide overcurrent protection within the harness itself, further integrating safety features and reducing external components (’295 Patent, Abstract; col. 2:5-12).
• Asserted Claims: At least independent claim 1 is asserted (Compl. ¶85).
• Accused Features: The Voltage LYNX Trunk Bus products are accused of infringing the ’295 Patent (Compl. ¶31, ¶84).

III. The Accused Instrumentality

Product Identification

• The "Voltage LYNX Trunk Bus" and what Voltage has publicly referred to as its "alternative LYNX design" (collectively, the "Accused Products") (Compl. ¶31).

Functionality and Market Context

• The complaint describes the Accused Products as lead assemblies or solar wire harness systems used for connecting components in solar energy projects (Compl. ¶21, ¶31). Visuals provided in the complaint depict the Voltage LYNX Trunk Bus as a pre-fabricated cable assembly with a main, larger-gauge "trunk" cable and multiple overmolded junctions from which smaller "drop" cables emerge (Compl. ¶35, Fig. 1). An exemplary configuration shows these assemblies arranged to collect power from rows of solar panels, consolidating the wiring onto the main trunk bus (Compl. ¶35, Fig. 2). Plaintiff alleges that these products compete directly with its own "Big Lead Assembly (BLA)" products and that Defendants' infringement has resulted in lost sales (Compl. ¶36, ¶41).

IV. Analysis of Infringement Allegations

The complaint references claim charts in exhibits that were not provided. The following is a summary of the narrative infringement theories.

’375 Patent Infringement Allegations

The complaint alleges that the Accused Products practice all elements of at least claim 1 of the ’375 Patent (Compl. ¶51). The infringement theory appears to map the physical components of the Voltage LYNX Trunk Bus to the elements of the claim. The main cable of the accused product is alleged to be the claimed "feeder cable," the smaller cables are the "drop lines," and the overmolded junction shown in the complaint's Figure 1 is the "monolithic mold that encapsulates the nexus" (Compl. ¶35, Fig. 1). The product is alleged to be used to combine power from solar panels, thereby meeting the functional limitations of the claim (Compl. ¶50).

’376 Patent Infringement Allegations

The complaint alleges that the Accused Products meet each element of at least claim 1 of the ’376 Patent (Compl. ¶61). This allegation appears to rely on the physical configuration of the Accused Products, where the overmolded junction connects two drop lines to the main feeder cable. A photograph of the accused lead assembly shows two drop lines emerging from opposite sides of the molded housing (Compl. ¶35, Fig. 1). This feature is alleged to meet the claim 1 limitation requiring first and second drop lines that "extend in opposite directions along a longitudinal axis that is parallel to a longitudinal axis of the feeder cable" (’376 Patent, claim 1).

Identified Points of Contention

• Scope Questions: A potential issue for the ’375 Patent is the proper construction of "monolithic mold." The patent specification describes both a two-step undermold/overmold process and a single-step overmold process (’375 Patent, col. 6:1-13). Whether the accused product's mold, if formed by a multi-step process, can be considered "monolithic" may become a central point of dispute.
• Technical Questions: For the ’376 Patent, a key question may arise from the geometric requirement that the drop lines extend along an axis "parallel" to the feeder cable. The visual evidence shows the drop lines exiting the molded body at a distinct outward angle, not in a strictly parallel orientation to the main cable (Compl. ¶35, Fig. 1). The infringement analysis may turn on whether this angled configuration falls within the scope of the term "parallel," either literally or under the doctrine of equivalents.

V. Key Claim Terms for Construction

• The Term: "monolithic mold" (from ’375 Patent, claim 1)
• Context and Importance: The protective enclosure over the electrical connection is a core feature of the invention. The definition of "monolithic" is critical because it could either broadly cover any single-body enclosure or be narrowly limited to enclosures formed by a specific, single-step manufacturing process.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The claim uses the term "monolithic mold" without specifying its method of formation. Parties may argue this term should be given its plain and ordinary meaning of being a single, solid, unitary piece, regardless of whether it was formed in one or multiple steps. The specification’s emphasis is on the final product being "profoundly durable" and resistant to environmental factors, suggesting function is more important than formation method (’375 Patent, col. 6:6-10).
  • Evidence for a Narrower Interpretation: The specification discloses the preferred embodiment as an undermold surrounded by an overmold, but then describes an "alternative embodiment" with "no undermold, just an overmold, which is applied in a single molding process" (’375 Patent, col. 6:11-13). A party could argue that the patentee used "monolithic" to specifically distinguish this single-step alternative from the preferred two-step process.
• The Term: "parallel to a longitudinal axis of the feeder cable" (from ’376 Patent, claim 1)
• Context and Importance: This geometric limitation defines the orientation of the drop lines relative to the main cable. Infringement will depend on whether this term requires strict geometric parallelism or can encompass the angled orientation depicted in the complaint's image of the accused product.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: Practitioners may argue that in the context of a flexible cable assembly, "parallel" should not be interpreted with rigid, geometric strictness. The patent figures themselves, such as FIG. 31, depict drop lines exiting the mold at a slight angle rather than being perfectly parallel (’376 Patent, Fig. 31). This may suggest the term is meant to describe a general co-linear arrangement rather than a precise geometric relationship.
  • Evidence for a Narrower Interpretation: The claim language is specific, reciting an "axis that is parallel." A party could argue that if the patentee had intended to claim a broader, angled configuration, different language would have been used. The patent distinguishes between configurations for different types of solar panels (e.g., crystalline vs. thin film), which may support an argument that specific layouts and geometries are meaningful limitations (’376 Patent, col. 5:6-15).

VI. Other Allegations

Indirect Infringement

• The complaint alleges both induced and contributory infringement. Inducement is based on allegations that Defendants encourage infringement by providing customers with promotional materials, product manuals, and instructions (Compl. ¶53, ¶63, ¶87). Contributory infringement is alleged on the basis that the Accused Products are especially made for use in an infringing manner and are not staple articles of commerce with substantial non-infringing uses (Compl. ¶54, ¶64, ¶88).

Willful Infringement

• Willfulness is alleged based on Defendants' alleged pre-suit and post-suit knowledge of the patents. The complaint asserts pre-suit knowledge based on Defendants' "investigation and monitoring of Shoals patents," including an instance where Voltage allegedly cited family members of the Asserted Patents in an Information Disclosure Statement filed with the USPTO (Compl. ¶37). It also alleges knowledge dating from at least the issue dates of the patents (Compl. ¶38).

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

• A central dispute will be one of claim construction and factual application: Can the term "monolithic mold" (’375 Patent) be construed to cover a structure made in a multi-step molding process, and can the geometric limitation requiring drop lines to be "parallel" to the feeder cable (’376 Patent) read on the visibly angled configuration of the accused product?
• A second critical issue will concern evidence of intent and improper conduct: The allegations that Defendants misused confidential information from a parallel ITC proceeding to design new products (Compl. ¶45-46) and knowingly copied patented technology, as evidenced by their own patent prosecution filings (Compl. ¶37), will be a primary focus for the claims of willful infringement and unfair competition.
• A third key question will be one of causation and damages: Assuming infringement is found, the case will require a detailed analysis of the market for EBOS solutions to determine the extent to which Plaintiff's lost sales were directly caused by Defendants' infringing activities, as opposed to other competitive factors.