Multinational retail giant Costco has initiated legal proceedings against the Trump administration, seeking a refund of import duties should the Supreme Court rule the tariffs unconstitutional. The lawsuit, filed with the US Court of International Trade, contests the administration's use of the International Emergency Economic Powers Act (IEEPA) to impose tariffs without congressional consent.

Legal Battle Over Tariff Authority

Costco's legal challenge comes after two lower courts determined that former President Donald Trump exceeded his authority by using emergency powers to levy tariffs. The Supreme Court, which heard arguments in November, is expected to deliver its verdict in the spring. Chief Justice John Roberts expressed skepticism over the administration's interpretation of IEEPA, emphasizing that taxation is traditionally a congressional power.

Financial Implications for Importers

The stakes are high, as the US government has collected $195 billion in tariffs in fiscal year 2025 alone. Costco, which imports a significant portion of its products, argues that the tariffs have adversely affected its business. The company is concerned about the potential loss of refunds if the Supreme Court upholds previous rulings against the tariffs.

Urgent Legal Action

Costco's lawsuit seeks to prevent the liquidation of tariffs by Customs and Border Protection, which finalizes tariff amounts 314 days after goods enter the US. The company fears that without a court order, importers may be unable to recover tariffs paid, even if deemed unlawful. The lawsuit demands that the court declare the tariffs illegal and order a refund for any duties paid under the contested authority.