First Solar, Inc. (NASDAQ: FSLR) has filed a patent infringement lawsuit against JA Solar Technology Co., Ltd., JA Solar International, Ltd., JA Solar Vietnam Co., Ltd., JA Solar Industrial Corp., and American Panel Solutions LLC in the United States District Court for the District of Delaware.

The lawsuit alleges infringement of First Solar's U.S. Patent No. 9,130,074, which covers methods of manufacturing Tunnel Oxide Passivated Contact (TOPCon) crystalline silicon photovoltaic solar cells.

First Solar acquired its TOPCon patent portfolio through its 2013 acquisition of TetraSun, Inc. The portfolio includes issued patents in the United States, Australia, Canada, China, the European Union, Hong Kong, Japan, Mexico, Malaysia, Singapore, South Korea, the United Arab Emirates, and Vietnam, with validities extending to 2030 and beyond. Pending applications exist in the European Union, Japan, Hong Kong, the United Arab Emirates, and Vietnam.

In July 2024, First Solar announced ownership of the TOPCon patent portfolio and launched infringement investigations against several crystalline silicon solar cell manufacturers.

"We have been clear that we will actively defend our intellectual property rights in the US and internationally," said Jason Dymbort, Executive Vice President, General Counsel and Secretary of First Solar. "This lawsuit is an effort to hold JA Solar and AMPS accountable for their unauthorized use of First Solar's patented technology and reinforces the need for TOPCon manufacturers operating in the United States to respect the well-defined framework of intellectual property law."