CSI Solar, a Chinese unit of Canadian Solar, has denied photovoltaic module maker Trina Solar's patent infringement claims.

CSI's products and processes do not infringe on the two patents cited in Trina's lawsuit, the Suzhou-based firm announced yesterday.

On Feb. 10, Changzhou-headquartered Trina filed two lawsuits against CSI and its Changshu subsidiary, alleging infringement of two core patents and seeking nearly CNY1.1 billion (USD145 million) in compensation.

A source at Trina told Yicai yesterday that whether there was a breach can be determined based on manufacturing technology usage, and the legal department is currently calculating CSI's profits derived from Trina's patented technologies. The patents in question relate to solar modules and manufacturing methods of solar cells.

CSI stated that Trina's claims against CSI and its Changshu unit lack factual and legal basis, adding that the company has conducted thorough research and analysis of the patents involved and believes it has strong evidence to prove they should be invalid.

CSI revealed that it submitted invalidation requests regarding both patents last year, which are currently under review by the China National Intellectual Property Administration.

Trina filed a lawsuit against Canadian Solar's wholly-owned subsidiary in the US federal court of Delaware last October regarding the US family of the solar cell patent. Trina also initiated a Section 337 investigation with the US International Trade Commission to investigate a potential intellectual property violation. The case has been temporarily suspended, pending an ITC decision.

The ITC is scheduled to hear the case this October, issue a preliminary determination in January 2026, and make a final decision in May 2026.

CSI also noted that India's Adani Group and Jiangsu province-based solar cell firm Runergy New Energy Technology have filed for invalidation of Trina's manufacturing technology patent with the US Patent and Trademark Office. The Canadian company's unit is closely monitoring the outcome.

This is not the first legal dispute between the two competitors. Last October, CSI sued Trina for alleged infringement of two patents in the Suzhou Intermediate People's Court, seeking compensation of CNY100 million (USD13.8 million). Both cases remain ongoing.