Why is First Solar stock climbing today?

First Solar (FSLR) sued JA Solar and Corning's (GLW) subsidiary, American Panel Solutions, for patent infringement related to TOPCon solar cell technology. The case was filed in Delaware court on October 1. First Solar acquired the patents in 2013 and has filed similar lawsuits against other solar companies this year.

First Solar filed a patent infringement lawsuit against JA Solar and Corning's subsidiary American Panel Solutions in U.S. District Court on October 1, alleging infringement of its solar PV technology patents.

First Solar (FSLR) sued JA Solar and affiliates for patent infringement over Tunnel Oxide Passivated Contact tech, filed in Delaware court. FSLR acquired the patents in 2013, valid globally until 2030. The company plans to defend its IP rights actively. In July, FSLR launched infringement probes against other solar cell makers.

First Solar is withdrawing its Section 337 complaint with the USITC but will continue patent lawsuits against Canadian Solar, Jinko Solar, T1 Energy, and Trina Solar in US District Court. The company plans to enforce its global TOPCon patent portfolio, pausing enforcement efforts after the Section 337 complaint. This follows a Trump Administration action under Section 232 aimed at polysilicon imports.

First Solar (FSLR) shares fell 11% on Thursday, heading for their worst week in six weeks. Roth Capital cited concerns over solar-module pricing but sees the recent weakness as a buying opportunity. The Commerce Department's crackdown on polysilicon stockpiling could benefit domestic solar manufacturers. FSLR reported mixed Q2 results with revenue down 4% to $1.06B but earnings up 23% to $3.92 per share.

Enphase Energy (ENPH) fell 5% to $34.29, while First Solar (FSLR) and Sunrun (RUN) each dropped 4%, driven by broader solar sector weakness. The decline follows a Fed rate hike, which impacts residential solar demand due to financing costs. The Invesco Solar ETF (TAN) also fell 2%, while the S&P 500 ETF (SPY) declined 0.2%.