Processing ContentVisa agreed Monday to pay $2.4 billion for a company that watches not card transactions but how bank customers type. The deal hands Visa a fraud tool already installed across much of U.S. retail banking. BioCatch protects 760 million users and serves more than 350 banking clients, analyzing 19 billion sessions a month, according to Visa's Monday announcement . Once the deal closes, the U.S. banks running BioCatch will buy their fraud detection from a company with which they also negotiate card terms. The complaint asks the court to bar Visa from "bundling credit services or credit incentives with debit network services."