Costco Wholesale Corporation, the nation's largest warehouse club chain, has filed a federal lawsuit against the US government challenging the legality of sweeping tariffs imposed earlier this year. The company is seeking a full refund of all duties already paid, arguing that the administration, led by President Donald Trump, exceeded its constitutional and statutory authority by relying on the International Emergency Economic Powers Act (IEEPA) to impose the levies. Costco's move places it among a rapidly growing list of major corporations suing to secure their eligibility for billions in refunds if the tariffs are ultimately struck down by the Supreme Court.The lawsuit, filed in the U.S. Court of International Trade, specifically targets
