Multinational retail giant Costco has sued the US government to secure a full refund of import duties if the Supreme Court rejects President Donald Trump's authority to impose tariffs without congressional approval.
Costco's lawsuit urges the federal trade court to declare Trump's 'emergency' tariffs illegal, an authority the president claims under the International Emergency Economic Powers Act (IEEPA).
Two lower courts have already ruled that Trump exceeded his authority by using emergency powers to impose tariffs.
The case has now reached the Supreme Court, where several companies are aiming to protect their rights to refunds should the justices invalidate the tariffs.
In the lawsuit filed over the Thanksgiving holiday, Costco asserted its business had suffered due to the tariffs and expressed concerns about not receiving refunds even if the Supreme Court upheld previous rulings.
Lawyers for Costco emphasized that a separate action is necessary since reimbursement is not guaranteed in the absence of their own judgment and judicial relief.
The world's third-largest retailer did not specify the exact amount sought, but trade data shows that importers like Costco have already paid approximately $90 billion in IEEPA-related tariffs by late September.
Costco filed the suit in the U.S. Court of International Trade ahead of a December 15, 2025, deadline, by which time it would face challenges in reclaiming any funds paid to the government.
In May, the court became the first to rule that Trump's tariffs were unlawful, a decision reaffirmed by the U.S. Court of Appeals.
During last month's hearing, Supreme Court judges expressed skepticism about the president's authority to impose tariffs without congressional approval.
Trump administration lawyers contended that emergent powers grant the president the ability to levy these global tariffs.
The administration warned that an adverse ruling could hamper its negotiation capacity with other nations and lead to a loss of billions already collected.
The economic consequences of failing to uphold President Trump's lawful tariffs are enormous, and this suit underscores that fact, White House spokesperson Kush Desai stated. The White House looks forward to the Supreme Court's swift and proper resolution of this matter, he added.
Last month, Trump claimed that the U.S. was taking in Trillions of Dollars from tariffs, forecasting a dividend of at least $2000 per person (excluding high-income individuals).
