Costco has filed a lawsuit against the US government demanding a full refund of import tariffs placed under former President Donald Trump’s emergency powers. The company argues these tariffs were imposed illegally, saying, "a separate action is necessary" to secure refunds since previous court rulings do not guarantee them. Two lower courts ruled that Trump overstepped his authority by imposing tariffs without Congress's approval. The case has now reached the Supreme Court, where several companies want the right to refunds if the tariffs are struck down. Costco has not disclosed the refund amount but US customs data shows importers paid about $90 billion in such tariffs by late September. The suit was filed before the December 15, 2025 deadline after which recovering funds could be harder. Trump’s emergency tariffs were first ruled unlawful in May by the US Court of International Trade and later by the Court of Appeals. At a recent Supreme Court hearing, judges were doubtful of Trump’s authority under the International Emergency Economic Powers Act (IEEPA). The Trump administration defends the tariffs, warning that a harsh ruling could harm US trade negotiations and cost the Treasury billions. White House spokesperson Kush Desai said, "The economic consequences of the failure to uphold President Trump's lawful tariffs are enormous and this suit highlights that fact." President Trump recently claimed the US was "taking in Trillions of Dollars" from tariffs and promised a "dividend of at least $2000 a person (not including high income people!) will be paid to everyone."