The patent war in the photovoltaic industry has escalated further, with U.S.-based solar company First Solar formally filing a Section 337 investigation application with the U.S. International Trade Commission (ITC) under the Tariff Act of 1930. The complaint directly targets competitors in the crystalline silicon photovoltaic module sector, alleging infringement of its core TOPCon patents. Ten companies are implicated: Axitec, Canadian Solar, JA Solar, Jinko Solar, Mundra (Adani), Philadelphia Solar, Qcells, Runergy, Trina Solar (including T1 Energy), and VSUN (Toyo). This marks another critical juncture in the overseas patent disputes within the photovoltaic industry.
The core of this investigation centers on First Solar’s U.S. Patent No. 9,130,074, a patent covering crystalline silicon photovoltaic modules related to Tunnel Oxide Passivated Contact (TOPCon) technology. As a leading company in the Cadmium Telluride (CdTe) thin-film photovoltaic module sector, First Solar’s enforcement action concerning TOPCon patents is backed by a clear industrial strategy.
It is reported that First Solar has licensed this TOPCon patent to photovoltaic cell startup Talon PV, which is currently establishing a cell production facility outside Houston. Talon PV plans to supply M10 and G12 format TOPCon cells to U.S.-based module assemblers starting next year. Leveraging this domestic industrial presence, First Solar has gained standing to petition the U.S. government to review patent infringement claims regarding imported TOPCon products. In this instance, it is directly petitioning the ITC to issue a General Exclusion Order covering all TOPCon photovoltaic cells manufactured using its patented technology intended for import into the U.S. market. Photovoltaic modules produced from such cells would also fall under the scope of the exclusion order.
This investigation did not emerge without precedent. Late in 2025, the U.S. Patent and Trademark Office rejected patent challenges filed by Jinko Solar, Mundra, and Canadian Solar against First Solar, setting the stage for this Section 337 investigation. First Solar’s formal filing followed the patent licensing agreement with Talon PV.
In fact, TOPCon patents have long been a focal point of dispute within the photovoltaic industry, with patent battles surrounding this technology persisting for some time. Most major manufacturers are entangled in patent litigation to varying degrees, a situation that is profoundly impacting the landscape of U.S. domestic photovoltaic manufacturing. To navigate the complex patent disputes, the few existing photovoltaic cell manufacturers in the U.S. have opted to continue using PERC cell technology, temporarily postponing the deployment of advanced N-type module production lines.
The significance of this patent dispute extends far beyond the ownership of a single technology. Securing the legal right to produce advanced N-type photovoltaic modules within the U.S. will directly influence companies’ market strategies and development prospects. Protracted legal battles could further widen the technological and capacity gap for the U.S. photovoltaic module manufacturing industry, which already lags behind China.
It is worth noting that this is not the first time TOPCon patents have triggered a Section 337 investigation in the photovoltaic industry. In 2024, Trina Solar filed a Section 337 complaint with the ITC based on related TOPCon patents, accusing Runergy, Mundra/Adani, and Canadian Solar of infringement. However, that investigation was completely terminated in February 2026 at Trina Solar’s own request.
From a thin-film solar company cross-sectorally enforcing TOPCon patents to multiple leading companies becoming embroiled in overseas patent litigation, global competition in the photovoltaic industry is extending beyond a contest of production capacity and technology to encompass comprehensive strategic patent positioning. How the Section 337 investigation initiated by First Solar will unfold, and how the implicated companies will respond, will not only impact the overseas market strategies of the involved firms but also shape the global industrial development landscape for TOPCon technology. We will continue to monitor this situation closely.
