Discount retail chain Costco Wholesale Corporation has filed a lawsuit against the United States and U.S. Customs and Border Protection to ensure it can recover money paid under disputed tariff orders while the Supreme Court considers their legality.

The complaint, filed Nov. 28 in the U.S. Court of International Trade, challenges duties imposed by President Donald Trump under the International Emergency Economic Powers Act. The retailer argues the executive branch lacks the statutory authority to levy taxes on imports under the act.

Costco’s legal action comes weeks after the Supreme Court heard oral arguments on Nov. 5 in consolidated cases challenging the same tariffs, including Learning Resources, Inc. v. Trump and V.O.S. Selections, Inc. v. Trump. While the high court is expected to rule soon, Costco states in court documents that immediate intervention is necessary to protect its financial interests.

According to the filing, the customs entries for Costco’s imported goods are scheduled to begin finalization, or liquidation, as early as Dec. 15. The company asserts that once these entries liquidate, it may lose its legal right to a refund even if the Supreme Court later declares the tariffs unlawful.

Costco requested that Customs and Border Protection extend the liquidation deadline, but the agency denied that request on Nov. 18.

The lawsuit cites a recent decision by the U.S. Court of Appeals for the Federal Circuit, which affirmed that the Emergency Powers Act allows the president to regulate or prohibit transactions but does not grant the power to impose duties. Costco argues the challenged orders are virtually identical to those already deemed invalid by the appellate court.

The tariffs in question include levies on goods from China, Canada, and Mexico, as well as reciprocal tariffs applied to imports from 57 other countries. The complaint states the company has paid these duties continuously and faces irreparable harm if the government finalizes the collections before a judicial ruling.

Costco is seeking a declaratory judgment that the tariffs are unauthorized, an injunction preventing further enforcement, and a full refund of all duties paid under the challenged orders.