US ITC Opens Section 337 Probe Into Global TOPCon Supply Chain

Why It Matters

A Section 337 exclusion could shut down TOPCon imports to the US, reshaping the solar supply chain and raising IP risk for global manufacturers.

Key Takeaways

• ITC launches Section 337 probe on TOPCon technology
• First Solar alleges infringement of patents 1,2,4,8
• 47 respondents span 11 countries, including major manufacturers
• Potential general exclusion order could block all TOPCon imports
• Respondents have 20 days to answer, risk default

Pulse Analysis

Tunnel‑oxide passivated contact (TOPCon) cells have become the leading n‑type silicon technology for high‑efficiency solar modules, especially in China where manufacturers such as JinkoSolar, Trina Solar and Canadian Solar dominate export volumes. The architecture combines a thin tunnel‑oxide layer with a doped contact, delivering efficiencies above 24 % and superior temperature coefficients compared with traditional p‑type cells. Because TOPCon modules command premium pricing in utility‑scale projects, they have rapidly become the backbone of the global supply chain feeding the United States, Europe and emerging markets. The US International Trade Commission’s Section 337 investigation marks a shift from trade‑policy tools to direct intellectual‑property enforcement.

S. Patent 9,130,074, alleging that imported TOPCon products infringe its proprietary passivation process. Unlike anti‑dumping duties, a general exclusion order can bar any product embodying the disputed technology, regardless of the importer, potentially cutting off the bulk of Chinese‑origin TOPCon modules. The USPTO’s recent refusal to invalidate the patents reinforces First Solar’s position, raising the stakes for the 47 named respondents.

Stakeholders must now weigh litigation risk against supply‑chain continuity. Companies that can redesign cells to avoid the patented features may preserve market access, while those awaiting a ruling face possible default judgments if they miss the 20‑day response deadline. Investors are likely to reassess exposure to TOPCon‑centric manufacturers, and buyers may diversify toward alternative high‑efficiency technologies such as heterojunction (HJT) or bifacial silicon. The outcome of this probe will signal how aggressively the US will protect domestic IP in a sector critical to clean‑energy goals.