Lloyd Constantine ‘72 won a $3 billion settlement from Visa USA and MasterCard International involving a lawsuit over the companies' debit card policies. His clients, which included Wal-Mart and millions of other retail stores, were fighting a requirement that merchants who took the credit cards also must accept VISA and MasterCard debit cards. The case will transform the credit card industry in which the two dominant companies used their influence to charge high fees from merchants when customers used debit cards, Mr. Constantine told the New York Times. Lower fees could save more than $100 billion over the next 10 years, a savings passed on to merchants and consumers. Mr. Constantine, who specializes in antitrust law, started his New York based firm, Constantine and Partners, 10 years ago.