Costco, one of the thousands of businesses that is seeking refunds, did not respond to a request for comment.
Speaking to analysts after reporting earnings this month, chief executive Ron Vachris said it remained unclear “what refunds, if any, will be received”, adding that in many cases the company had not passed on the “full cost” of the duties.
“As we have done in the past, when legal challenges have recovered charges passed on in some form to our members, our commitment will be to find the best way to return this value to our members through lower prices and better values,” he added.
“We will be transparent in how we plan to do this if and when we receive any refunds.”