Wal-Mart sues Visa for fixing price of credit card fees

``Giant US retailer Wal-Mart has sued credit card firm Visa for $5bn, alleging that Visa worked with large banks to fix the price of transaction fees it charged to Wal-Mart. The move comes after Wal-Mart opted out of a $5.7bn settlement with Visa and Mastercard in December. Wal-Mart and other US retailers, such as Target, objected to the terms of that agreement.''