Costco is joining other companies that aren't waiting to see whether the Supreme Court strikes down President Donald Trump's most sweeping import taxes. They're going to court to demand refunds on the tariffs they've paid.

The specialized U.S. Court of International Trade in New York and the U.S. Court of Appeals for the Federal Circuit in Washington ruled earlier this year that Trump's biggest and boldest import taxes are illegal.

The case is now before the Supreme Court. In a Nov. 5 hearing, several of the high court's justices expressed doubts that the president had sweeping power to declare national emergencies to slap tariffs on goods from almost every country on earth.

Trump claims that he has an almost unlimited right to impose tariffs — a power the Constitution gives to Congress, under the 1977 International Emergency Economic Powers Act (IEEPA) — but has now lost twice in court.

In a complaint filed last week with the trade court in New York, Costco said it is demanding the money back now “to ensure that its right to a complete refund is not jeopardized.″

The operator of warehouse-sized stores expressed concern that it might struggle to get a refund once its tariff bills have been finalized — a process called "liquidation'' — by the Customs and Border Protection agency, a process Costco says will start Dec. 15.

Revlon and canned seafood and chicken producer Bumble Bee Foods have made similar arguments in the trade court.

The tariffs facing the court challenge have raised around $90 billion so far.

Trump warned back in August that the loss of his tariffs would destroy that American economy and lead to "1929 all over again, a GREAT DEPRESSION!”