As we noted in our previous articles HERE and HERE, on February 20, 2026, the U.S. Supreme Court held that President Donald Trump lacked authority under the International Emergency Economic Powers Act to impose tariffs. This removed the legal basis for the entire package of tariffs introduced under the IEEPA regime. Although the White House responded immediately by introducing a new temporary tariff regime under a different legal authority, that regime applies only from February 24, 2026 onward and is effective only with respect to future imports. For that reason, attention is now shifting to what should happen to the amounts that were collected under IEEPA before the U.S. Supreme Court intervened.
The new tariffs do not apply to earlier imports
For any further legal assessment and for the practical assertion of claims, it is essential to distinguish carefully between two regimes that are different both in time and in law. The first is the period during which tariffs were collected under the IEEPA regime. The second is the subsequent period following the U.S. Supreme Court’s decision, in which the Administration introduced a new temporary tariff regime under a different statutory basis. These two regimes cannot be legally conflated, nor can their effects be treated as interchangeable.
The new tariffs introduced under Section 122 of the Trade Act of 1974 did not take effect until February 24, 2026. That timing alone makes clear that they cannot apply to imports for which duties were assessed and paid while the IEEPA regime was still in force. The new tariff regime therefore has no retroactive effect and cannot retrospectively supply legal validity to duties that were collected during the earlier period without a valid legal basis.
What matters for affected parties is that duties paid while the IEEPA regime was in force must be assessed separately, on the basis of the legal framework that existed at the time the specific customs obligation arose and was paid. The subsequent introduction of a new temporary regime therefore does not alter the fact that a claim may arise for the refund of duties paid during the earlier period.
Refund litigation has already begun
Immediately after the U.S. Supreme Court’s decision, it became clear that the issue of refunds would not remain confined to academic debate. Hundreds of disputes concerning refunds of duties paid under this regime are now before the Court of International Trade. These are not marginal cases. According to available information, thousands of lawsuits have already been filed, and the proceedings involve not only smaller importers but also major international companies that were directly affected by the tariff burden imposed under IEEPA. This is an important signal to other market participants. The issue is no longer merely an abstract possibility of recovering duties already paid, but a live and developing litigation agenda in which specific claims and further procedural steps vis-à-vis U.S. Customs are now being determined.
At its core, the argument advanced by claimants is straightforward. If the U.S. Supreme Court held that the President lacked authority to impose tariffs under IEEPA, then there is a basis for arguing that amounts collected on that basis were collected without proper legal authority. It follows that such amounts should be returned to the entities that paid them during the relevant period.
The sums at issue are not insignificant. Earlier expert estimates placed the total amount involved at more than USD 175 billion.
Refunds may also trigger further disputes within the supply chain
In practice, the refund agenda may not be exhausted by litigation against U.S. authorities alone. It is becoming increasingly clear that, once a right to repayment is confirmed, a further commercially significant question may arise: who should ultimately be entitled to the refunded amount. From a customs law perspective, the decisive party is often the importer that formally paid the duty. From a commercial perspective, however, that is frequently not the party that ultimately bore the economic burden. In many cases, the increased costs were passed through into prices, special surcharges, distribution terms, or contractual mechanisms between individual participants in the supply chain. For that reason, it can be expected that, alongside the public law dispute over refunds, a private law dimension may also emerge among importers, suppliers, shippers, and customers.
This development is no longer merely hypothetical. After filing its claim, FedEx publicly stated that if it recovered a refund, it intended to pass that refund on to the shippers and customers who had borne those costs. Almost immediately thereafter, however, customers filed a separate lawsuit arguing that the company’s public undertaking was not legally sufficient. This is a highly significant signal. It shows that while the finding that the IEEPA tariffs were unlawful has opened the door to refunds, it has also created new scope for disputes over who is the true bearer of the economic loss and who should benefit from any amounts returned.
Recovering refunds will require careful procedural and evidentiary preparation
If affected entities decide to actively pursue claims for the repayment of duties paid under the IEEPA regime, they will first need to undertake a precise factual, documentary, and contractual mapping of the entire matter. First and foremost, it will be necessary to identify the specific imports for which duties were assessed and paid, determine who acted as the importer or declarant in each case, and secure complete customs and payment documentation for every individual transaction. It will be equally important to review the commercial and contractual dimension of the matter, including whether and how the duty burden was passed on to the next link in the supply chain, who may be the holder of the refund claim, and whether the contractual documentation governs who should receive any refunded amount or who is required to take steps to obtain it. It is therefore already clear that any attempt to recover refunds will not turn on a general reference to the U.S. Supreme Court’s decision, but above all on thorough procedural preparedness, the quality of the underlying documentation, and the ability to distinguish precisely between claims relating to the IEEPA period and the new tariff regime that applies prospectively.
Conclusion
Following the U.S. Supreme Court’s decision, it is clear that the dispute over Trump’s IEEPA tariffs is not ending, but is instead entering the phase of actual refund enforcement. For affected parties, this is no longer merely a general legal issue. It is now a matter of identifying the relevant imports in time, preparing the necessary evidentiary record, and properly structuring the next steps.
Our law firm is widely regarded as one of the leading firms in the field of customs and tax law, and we devote sustained attention to this area. We are able to provide clients with legal assessment of potential refund claims, preparation of the appropriate strategy, and coordination of the matter with foreign partners. We also maintain a network of partner law firms abroad, which allows us to coordinate effectively the cross-border aspects of this agenda, including any follow-on litigation steps.
