Following the Supreme Court’s February ruling that invalidated tariffs collected under the International Emergency Economic Powers Act, U.S. Customs and Border Protection launched Phase 1 of its refund processing system Monday, opening a $127 billion claims window for more than 330,000 importers.

The system, called CAPE (Consolidated Administration and Processing of Entries), lets importers and authorized customs brokers file refund declarations through their ACE Portal accounts. CBP built it to consolidate IEEPA duty refunds with interest rather than processing them entry-by-entry, a practical necessity given the scale.

The $127 billion is the share CBP can now accept refund claims for, out of the $166 billion it collected before the ruling. Citi analysts identified Walmart, Target, and Nike as the largest individual claimants: $10.2 billion, $2.2 billion, and $1 billion, respectively.

Don’t expect fast resolution. Walmart CFO John David Rainey called the process “very complex” on April 8, warning it wouldn’t happen quickly. Companies are also contending with bureaucratic hurdles, legal vulnerabilities, and the possibility of a Trump administration appeal. Fortune reported Sunday that CBP approval alone is followed by a 60-to-90-day wait for the actual refund.

Phase 1 is limited to certain unliquidated entries and entries within 80 days of liquidation. CBP said later phases will add functionality for more complicated scenarios.

A Court of International Trade judge ordered the government to file a progress report by April 28.

James Okafor