Visa Readies Market-Definition Fight in DOJ Debit Case

The U.S. Department of Justice sued Visa in federal court in Manhattan on Sept. 24, 2024, accusing the payments company of preserving an unlawful monopoly through restrictive contracts and payments to potential rivals. The DOJ says Visa routes more than 60% of U.S. debit transactions and collects over $7 billion in annual processing fees. Whether debit networks form a distinct antitrust market will determine how the court measures Visa’s power and any competitive harm.

U.S. District Judge John G. Koeltl denied Visa’s motion to dismiss on June 23, 2025, finding the DOJ had plausibly excluded interbank systems such as ACH and RTP at the pleading stage. As the case moved toward trial by Aug. 11, 2026, lawyers expected Visa to renew its argument that the government’s market is too narrow. A broader market including alternative payment rails could reduce Visa’s calculated share, making the court’s definition central to liability and any eventual remedy.