Wal-Mart has sued Visa for $5 billion, alleging that the credit card company worked with large banks to fix the price of transaction fees it charged to the retailer.
The move comes after Wal-Mart opted out of a $5.7 billion settlement with Visa and MasterCard in December.
Wal-Mart and other US retailers, such as Target, objected to the terms of that agreement.
Visa had sued Wal-Mart in June 2013 to prevent the firm from filing a lawsuit.
Wal-Mart, which is the world’s largest retailer, argues that Visa worked with large banks “to illegally fix the interchange fees and inflate the network fees that Wal-Mart and other merchants pay on Visa charge card transactions”.
Those large fees then caused “enormous damage” between 2004 and 2012, the retailer claims.
Wal-Mart is now suing Visa for damages, which it estimates to be over $5 billion.
Visa declined to comment on the lawsuit, which was filed this week in Fayetteville, Arkansas, near Wal-Mart’s headquarters.