Refile: First Solar drops ITC patent case, shifts focus to lawsuits against rivals

First Solar

16/09/2026 19:45

Fixes spelling of Jinko Solar
Sept 16 (Reuters) - U.S. solar panel maker First Solar Inc FSLR.O said on Wednesday it would withdraw a patent infringement complaint before the U.S. International Trade Commission and instead focus on pursuing lawsuits in federal court against rivals over a leading solar technology.
The Phoenix-based company said it plans to withdraw its Section 337 complaint and seek termination of the ITC investigation without prejudice, leaving open the possibility of refiling later.
First Solar said it will continue pursuing patent lawsuits in federal court against affiliates of Canadian Solar CSIQ.O, Jinko Solar JKS.N, T1 Energy TE.N and Trina Solar 688599.SS, cases that had been paused pending the ITC proceeding.
TOPCon, short for tunnel oxide passivated contact, is a high-efficiency crystalline silicon solar cell technology that has become one of the dominant solar technologies. First Solar does not manufacture silicon-based products, which include TOPCon, and instead makes cadmium telluride panels.
First Solar acquired the TOPCon patents through its 2013 purchase of TetraSun and began investigating potential infringement by major solar manufacturers in 2024.
T1 Energy said it would defend itself against any remaining claims: "T1 Energy is the only American company that both owns patents to high efficiency TOPCon solar and currently manufactures TOPCon solar modules," spokesperson Russell Gold said. "We are pleased that First Solar voluntarily withdrew what we believe was a flawed Sec. 337 complaint that would have slowed needed energy production at a time when the United States needs all the affordable electricity we can produce."
Canadian Solar, Jinko Solar and Trina Solar did not immediately respond to requests for comment.
First Solar said the decision to withdraw the complaint followed the Trump administration's recent proclamation imposing trade measures on imports of polysilicon and related solar products.
Shares of First Solar were down about 5% on Wednesday and touched their lowest level in roughly five months.

 (Reporting by Nichola Groom, Editing by Nick Zieminski)
 ((nichola.groom@thomsonreuters.com;))