Costco is suing the U.S. government over Trump’s tariffs. Here’s why

Costco has sued the U.S. government to ensure it will receive refunds if the Supreme Court rejects President Donald Trump’s bid for sweeping authority to impose tariffs.

In a complaint filed on Friday in the U.S. Court of International Trade in Manhattan, Costco said Trump’s use of the International Emergency Economic Powers Act to impose tariffs left it uncertain whether businesses can recoup sums they should not have paid.

The nation’s largest warehouse club operator said U.S. Customs and Border Protection denied its request for more time to make final calculations of tariffs owed, threatening its right to complete refunds even if the Supreme Court rules against Trump.

Customs and Border Protection had no immediate comment. Costco did not immediately respond to a request for comment.

Based in Issaquah, Washington, Costco joined dozens of companies suing to safeguard potential refunds. It is also among the largest, with $275.2 billion of revenue in its fiscal year ending August 31.

Other companies that have sued to preserve refunds include Bumble Bee Foods, Ray-Ban eyeglass maker EssilorLuxottica, Kawasaki Motors, Revlon, and Yokohama Tire, court records show.

During oral arguments on November 5, Supreme Court justices from both sides of the political spectrum asked skeptical questions about whether Trump legally used the 1977 emergency powers law to impose tariffs.

The justices took the case on an accelerated basis, but have not said when they will rule.

Costco has taken multiple steps to address tariffs, including by reducing the number of suppliers, and relying more on local sourcing and its in-house Kirkland brand.

—Jonathan Stempel, Reuters