The US Court of International Trade has ruled against Biden’s 2-year solar tariff moratorium on Southeast Asian imports
The industry fears billions in retroactive duties, with estimates ranging between $54 billion and $67 billion for 71 to 88 GW of imports
Coalition for a Prosperous America urges swift action and full collection by the Trump administration
Rhone Resch warns the ruling will also impact developers buying stockpiled FEOC modules for tax credits under OBBBA
USITC says it will continue AD/CVD investigations on solar imports from India, Indonesia, and Laos for alleged unfair trade
The US Court of International Trade (USCIT) has reportedly invalidated the 2-year moratorium on solar tariffs on imports from Southeast Asia announced by the former US President Joe Biden. Retroactive tariff collection fear has now gripped the market as industry projections indicate retroactive solar tariffs could reach several billion dollars following the ruling.
For the uninitiated, US solar manufacturer Auxin Solar had called for an investigation into companies, accusing them of evading US antidumping and countervailing duties (AD/CVD) by routing Chinese solar modules through Vietnam, Malaysia, Thailand, and Cambodia. The US Department of Commerce (DOC) later found some firms in violation, but President Biden’s proclamation granted a 24-month waiver on tariffs until June 2024. Auxin Solar and Concept Clean Energy challenged this moratorium in the USCIT, arguing it was unlawful (see Solar Companies Challenge US Govt Tariff Moratorium).
The August 22, 2025, ruling by USCIT Judge Timothy M. Reif in the Auxin Solar, Inc. v. United States case is the culmination of this investigation. However, the details of the public version have not been released as yet.
Back in 2024, analysts at ROTH believed the case had a strong chance of success, and it could lead to retroactive tariffs on $10 billion worth of solar panels imported duty-free since April 2022, even including installed modules.
Rhone Resch, the Founder, President and Chief Revenue Officer (CRO) of Silicon Valley technology company for utility-scale solar, Solarlytics, believes that these potential retroactive tariffs could be collected for ‘between 71 and 88 GWs’ of imports that entered the US during the moratorium period, worth ‘$54-67 billion’.
Resch seems to be citing the estimates shared by the Coalition for a Prosperous America (CPA) in March 2025, when it estimated $53.9 billion to $67.4 billion in tariff revenue as estimated retroactive duties on imports during the entire moratorium period, for 71 GW to 88 GW of capacity.
Following the USCIT ruling, CPA President Jon Toomey said, “The Court’s decision finally brings accountability, ensures billions in illegally suspended duties will be collected, and sends a strong signal that the U.S. must never again give China a free pass to dump subsidized solar products into our market.” He calls on the Trump administration to ‘act swiftly’ and collect the retroactive duties ‘in full’.
Formerly the President and CEO of the US Solar Energy Industries Association (SEIA), Resch says this ruling will impact all companies that brought solar panels from Southeast Asia into the US under the ‘tariff-holiday’, including the US subsidiaries of foreign manufacturers, large-scale solar developers, and module distributors.
In the present day America, where the solar industry is still adjusting to the One Big Beautiful Bill Act (OBBBA), what’s all the more concerning for the industry is that Resch believes this ruling will also impact developers planning to purchase stockpiled modules from Foreign Entity of Concern (FEOC) companies by the end of the year to qualify for the Investment Tax Credit (ITC) and Production Tax Credit (PTC).
Supporters of Biden’s tariff moratorium, including major solar companies and trade groups, now face 3 choices, believes Resch – appeal to the Federal Circuit, request an emergency stay to delay billions in retroactive duties, or lobby Washington for a political solution.
“This is a watershed moment in U.S. solar policy. It resets the table ahead of the 2026 FEOC deadline and signals that trade enforcement is back—and retroactive. Bottom line: The tariff holiday is over. Time to reassess your supply chains,” wrote Resch in a LinkedIn post.
Investigation to continue into solar imports from India, Indonesia, and Laos
Meanwhile, in a related development, the US International Trade Commission (USITC) has determined to continue its investigations into the import of solar cells and modules to the US from India, Indonesia, and Laos. The AD/CVD probe was petitioned by the Alliance for American Solar Manufacturing and Trade Committee (AASMTC) in August 2025 (see US Investigates Solar Trade From Laos, Indonesia & India).
The agency says it found reasonable indication that crystalline silicon solar cells, whether or not assembled into modules imported into the US from these 3 nations, have caused material injury to the local industry as these were sold at ‘less than fair value and subsidized’ by their respective governments.
USITC will announce its preliminary CVD determinations on or around October 10, 2025, while those for AD will be out on or about December 24, 2025.
TaiyangNews will explore the US solar market in view of the regulatory shifts at the upcoming RE+ 2025 event in Las Vegas, US. It is co-organizing the 2025 Solar Made in USA summit in collaboration with RE+ and EUPD Research. To be held on September 8, 2025, the event will feature leading names from the world of solar to discuss the future of US solar and storage manufacturing and future strategies for the players in light of the regulatory hurdles created by the OBBBA. Registrations are open and can be done here.