Costco files U.S. Court of International Trade suit for tariff refunds On December 1‑3, 2025 Costco lodged a complaint in the U.S. Court of International Trade in New York (Manhattan) seeking a full refund of duties imposed under President Trump’s 2018‑2020 emergency tariff program [1][2][3][4][5]. The retailer argues the tariffs exceed authority granted by the International Emergency Economic Powers Act (IEEPA) and cites $90 billion in tariffs already paid by importers [1][3][4][5]. Legal counsel Joyce Adetutu emphasized filing before the December 15 liquidation deadline to secure a judgment that could be enforced if the Supreme Court later overturns the tariffs [1].

Supreme Court hearing questions presidential emergency powers On November 5, 2025 the Court heard arguments questioning whether the president could unilaterally declare national emergencies to impose sweeping tariffs on almost every country [1][2][3][4][5]. Justices expressed skepticism, with Justice Gorsuch warning of executive‑power erosion and Chief Justice Roberts probing the scope of IEEPA [4]. The Court has not set a decision date; some reports suggest a ruling could arrive as early as later this year, while others anticipate a summer decision or by the end of the term in June 2026 [5][1].

Customs liquidation deadline tightens refund window Customs and Border Protection will begin tariff liquidation on December 15, 2025, after which importers have 180 days to protest the assessed bills [1][2][3][4]. Costco warned that a delayed Supreme Court ruling could shrink this protest period, jeopardizing its ability to claim refunds [1][2]. The liquidation process will finalize the $90 billion revenue stream for the Treasury, making the timing of any refund claim critical for large importers [1][3].

Industry-wide challenges target the same tariff regime Alongside Costco, firms such as Revlon, Bumble Bee Foods, EssilorLuxottica, Kawasaki Motors, Yokohama Tire and others have filed similar refund claims or lawsuits [1][4][5]. The contested tariffs include a 10 % baseline duty on most U.S. imports and additional 11‑50 % rates on 57 countries, notably Canada, Mexico and China [4]. These coordinated actions underscore broad commercial resistance to the emergency‑tariff framework and aim to preserve the right to recover billions in paid duties [4][5].

Government warns of significant economic fallout White House spokesperson Kush Desai cautioned that overturning the tariffs could have “enormous” economic consequences, stressing the Treasury’s concern over repaying nearly $90 billion [3]. The administration expects a “speedy and proper” Supreme Court resolution to avoid fiscal disruption [3]. Costco, with FY 2025 revenue of $275.2 billion, has mitigated tariff exposure by diversifying suppliers, boosting local sourcing, and expanding its Kirkland Signature brand [5].