The U.S. International Trade Commission (USITC) has initiated a Section 337 investigation into imports of Tunnel Oxide Passivated Contact (TOPCon) solar cells and modules, naming three Indian companies among a broad list of global manufacturers accused of patent infringement.

The investigation stems from a complaint filed by First Solar, a solar manufacturer headquartered in Arizona, alleging that multiple solar manufacturers are importing products that infringe its patents related to TOPCon solar cells.

Among the respondents identified by the USITC are Indian entities Mundra Solar PV, Mundra Solar Energy, and Adani Green Energy, alongside major international manufacturers such as JinkoSolar, Trina Solar, JA Solar, Canadian Solar, and Hanwha Q Cells.

The complaint alleges violations of Section 337 of the Tariff Act of 1930, which governs unfair trade practices in the importation of goods, particularly those involving intellectual property infringement.

First Solar has complained that these companies have imported or sold within the U.S. solar cells, modules, panels, and related components that infringe certain claims of its patents.

As part of the complaint, First Solar has requested that the USITC issue either a general exclusion order, which would block the import of infringing products from all sources, or a limited exclusion order targeting specific companies. It has also sought cease-and-desist orders to prevent further sale and distribution of the products within the U.S.

The USITC clarified that it has only instituted the investigation but has not reached any conclusion on the merits of the case. The matter will now be assigned to an administrative law judge, who will conduct proceedings including evidentiary hearings and issue an initial determination on whether a violation has occurred. This determination will subsequently be subject to a USITC review.

Within 45 days of instituting the investigation, USITC is expected to set a target date for completion of the proceedings. Section 337 investigations typically take several months to conclude.

If the USITC ultimately finds a violation, it may issue remedial orders, including import bans. Such orders become effective upon issuance but are subject to a 60-day presidential review period, during which the U.S. Trade Representative may disapprove them on policy grounds.

The case has significant implications for the global solar supply chain, given the wide range of companies involved across multiple jurisdictions, including the U.S., China, India, Southeast Asia, and Europe.

TOPCon technology is among the most advanced and widely adopted cell architectures in the solar industry, and any restrictions on its trade could have ripple effects on module availability, pricing, and project deployment.

The inclusion of Indian manufacturers underscores the increasingly globalized nature of solar manufacturing and the exposure of Indian firms to international trade disputes as they expand their presence in export markets.

Recently, the Office of the United States Trade Representative initiated a Section 301 investigation into structural excess capacity and production in manufacturing, with India among the economies under review. The investigation will examine whether policies or practices in these economies are contributing to structural overcapacity in manufacturing sectors that could distort global markets and harm U.S. commerce.