First Solar investigates major rivals for TOPCon patent infringement

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A First Solar manufacturing facility.
First Solar acquired its TOPCon patents when it bought TetraSun in 2013. Image: First Solar.

US-based cadmium telluride (CdTe) thin-film solar manufacturer First Solar is pursuing intellectual property infringement cases against five major Chinese solar manufacturers.

According to First Solar’s Q3 2024 earnings report, delivered last week, the cases are being pursued against JinkoSolar, Canadian Solar, JA Solar, LONGi and Trina Solar—collectively, five of the largest PV manufacturers in the world.  

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The cases relate to First Solar’s portfolio of tunnel oxide passivated contact (TOPCon) solar cell technology patents, which it acquired when it bought solar cell development firm TetraSun in 2013.

First Solar’s primary business produces CdTe thin-film modules, whereas TOPCon products are based on far more widespread crystalline silicon technology.

In the company’s earnings call last week, First Solar CEO Mark Widmar said the company had “begun to leverage” the portfolio “as part of our ongoing efforts to develop the next generation of PV technologies”.

Patent disputes between major solar manufacturers have become commonplace in recent months (premium access). Most recently, Trina Solar’s US business sued Canadian Solar over TOPCon imports to the US. The week prior, French manufacturing startup Carbon emerged as a third party in a TOPCon patent dispute between JA Solar and fellow Chinese manufacturer Astronergy.

According to Widmar’s comments, First Solar holds patents and patent applications in 13 jurisdictions, including the US and Malaysia (where it has manufacturing operations), China, Vietnam the UAE and the EU. He added that, whilst the company has no patents in India, “several jurisdictions where we do have patents are sourcing India-bound cell manufacturing and exports.”

First Solar first announced investigations into potential TOPCon patent infringements in July, though it did not name the companies in question.

Widmar continued: “We believe we will be able to assert our patent rights in these jurisdictions against manufacturers and exporters of infringing India-bound products. While a number of other market participants are claiming they too own TOPCon patents, it is important to note that as with any mature technology, it is not unusual that multiple key patents may be held by multiple unrelated parties.

“Without ownership or license covering every relevant patent used in the manufacturing process, a manufacturer does not have the freedom to produce and sell an otherwise infringing product.

“…we have recently begun sending letters to various solar manufacturers…providing notice to each recipient that they are using First Solar’s TOPCon patents without a license and reserving First Solar’s rights in their entirety.”

PV Tech has contacted the five companies and will update this article with any further comments.

Earnings call transcript from Motley Fool.

This article was amended to more accurately reflect First Solar’s position.

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