Federal Circuit Lets Shoals Withdraw Its Photovoltaic Connectors Appeal Over Voltage's Opposition and Awards Voltage Its Costs.

The order

In Shoals Technologies Group, LLC v. International Trade Commission, No. 2025-1439, a Federal Circuit panel of Circuit Judges Chen, Linn and Cunningham issued a nonprecedential per curiam order on October 22, 2026. The order considered Shoals' motion to voluntarily withdraw its appeal, which states that the Commission does not oppose, and the opposition of intervenors Voltage LLC and Ningbo Voltage Smart Production Co. (together, Voltage). The court granted the motion, dismissed the appeal, and awarded costs to Voltage. The appeal is from the Commission in Investigation No. 337-TA-1365, which the Commission terminated in January 2025 with a finding of no violation.

The complaint and the patents

Shoals Technologies Group, LLC of Portland, Tennessee, filed its section 337 complaint on May 4, 2023, and supplemented it on May 12, 2023. It alleged that photovoltaic connectors and components were imported and sold in violation of section 337 by reason of infringement of U.S. Patent 10,553,739 and U.S. Patent 10,992,254, and it asked for a limited exclusion order and cease and desist orders. The Commission instituted the investigation on June 5, 2023, with notice published June 9, 2023, on claims 1-13 and 15-18 of the '739 patent and claims 1-15 of the '254 patent. The notice described the accused products as "photovoltaic wire harnesses or string harnesses that contain one or more inline fuses, in-line fuse kits, and assemblies for connecting solar panel arrays to an inverter, which assemblies are called lead assemblies or trunk buses, and which may also include one or more in-line fuses."

The notice named eight respondents: Hikam America, Inc. of Chula Vista, California; Hikam Electrónica de México, S.A. de C.V. of Mexicali, Mexico; Hikam Tecnologia de Sinaloa of Guasave, Mexico; Hewtech Philippines Corp. of Laguna, Philippines; Hewtech Philippines Electronics Corp. of Pampanga, Philippines; Hewtech (Shenzhen) Electronics Co., Ltd. of Shenzhen, China (the Commission called these six the Hikam Respondents); Voltage, LLC of Chapel Hill, North Carolina; and Ningbo Voltage Smart Production Co. of Ningbo, China. The Office of Unfair Import Investigations was also a party.

The '739 patent, Photovoltaic In Line Fuse Connector Assembly Having an Integral Fuse, issued February 4, 2020. The '254 patent, Lead Assembly for Connecting Solar Panel Arrays to Inverter, issued April 27, 2021. U.S. Patent 11,689,153, which has the same title as the '254 patent and names Shoals Technologies Group, LLC as applicant and assignee, issued June 27, 2023, after the complaint was filed. On Shoals' unopposed motion, the administrative law judge amended the complaint and notice of investigation to add claims 1, 2-3, 6, 8, 11-18, 21, 23 and 24 of the '153 patent against Voltage (Order No. 5, July 18, 2023). Shoals argued that the '153 patent is a continuation of a patent already asserted, against the same respondents and products. The ALJ found good cause because Shoals could not have asserted the '153 patent in its original complaint, since the patent issued over a month after that complaint was filed. The ALJ also set a 17-month target date of November 12, 2024. The Commission declined to review either order on August 15, 2023.

Narrowing before the hearing, and a first appeal

On March 11, 2024, the Commission terminated a set of claims of all three patents on Shoals' withdrawal of the complaint as to those claims, and on March 25, 2024, it terminated the '254 patent on Shoals' withdrawal. The ALJ's February 20, 2024 claim construction order construed terms of all three patents, and the ALJ later denied Shoals' motion to reconsider the construction of "engaged with" in claims 1 and 10 of the '739 patent. On April 19, 2024, the Commission declined to review the ALJ's summary determination that Shoals had not satisfied the technical prong of the domestic industry requirement for the '739 patent, and so found no violation as to that patent. Because only the '739 patent was asserted against the Hikam Respondents, the Commission said they were effectively terminated from the investigation at that point.

Shoals filed a notice of appeal to the Federal Circuit on June 18, 2024, from the no-violation finding on the '739 patent, docketed as No. 24-1991. According to the Commission's January 2025 notice, the Federal Circuit dismissed that appeal on December 18, 2024, on a joint stipulation of voluntary dismissal. On April 26, 2024, the Commission also terminated claim 8 of the '153 patent on Shoals' withdrawal.

The hearing and the ALJ's violation finding

The ALJ held the evidentiary hearing on March 18-22, 2024. By then, Shoals asserted claims 1, 11-14, 18, 21, 23 and 24 of the '153 patent against the Voltage Trunk Bus, and Voltage sought adjudication of a redesign, the Voltage Alternative Design (AD) Trunk Bus, as to claims 21 and 24. Shoals asserted that its domestic industry product practices claims 1 and 21.

On August 30, 2024, the ALJ issued a final initial determination finding a violation of section 337 as to certain claims of the '153 patent. According to the Commission's notices, the final ID found that both trunk bus designs had been imported or sold for importation or after importation; that the Voltage Trunk Bus satisfies claims 1, 11-14 and 18 but not claims 21, 23 and 24; that the AD Trunk Bus satisfies none of the asserted claims; that Shoals satisfied both the technical and economic prongs of the domestic industry requirement; and that Voltage had not shown the asserted claims invalid under 35 U.S.C. 112 for lack of written description or indefiniteness. On September 13, 2024, the ALJ recommended a limited exclusion order against Voltage, if the Commission found a violation, and a bond of 100 percent during the period of Presidential review.

The Commission's reversal

All three parties petitioned for review on September 16, 2024. Shoals argued that the ALJ should not have considered the AD Trunk Bus as within the scope of the investigation. Voltage challenged the construction of "aperture," the findings that the asserted claims are not invalid under section 112, the domestic industry finding, and the exclusion of the testimony of its invalidity expert. The Office of Unfair Import Investigations sought review of the construction of the three "aperture" terms, the technical prong finding, and the same evidentiary ruling. On October 4, 2024, Voltage filed a notice of supplemental authority attaching a September 30, 2024 decision of the Patent Trial and Appeal Board denying Voltage's petition to institute post-grant review of the '153 patent, PGR2024-00022.

On November 13, 2024, the Commission determined to review the final ID's construction of the "aperture" terms, its infringement finding, its section 112 findings, and its domestic industry findings, asked the parties two questions about the record under the Office of Unfair Import Investigations' proposed construction, and extended the target date to January 15, 2025.

On January 14, 2025, the Commission construed the "aperture" terms so that the entire "drop line" recited in the claims means "the entire length of the underlying 'drop line/wire' within the undermold (and compression lug), just as the 'feeder cable' equates to the entire length of the underlying cable within the undermold (and compression lug)." It reversed the finding that the Voltage Trunk Bus satisfies claims 1, 11-14 and 18, and reversed the finding that Shoals' domestic industry products satisfy claims 1 and 21. It took no position on the other issues under review, issued an opinion explaining its determination, and terminated the investigation with a finding of no violation of section 337. Notice of the determination was published January 21, 2025.

What to watch next

Watch for the Federal Circuit's mandate and for Voltage's bill of costs under Fed. R. App. P. 39, which the order awards to Voltage.