Visa, MasterCard, Discover, American Express, Diners Club, UnionPay, and JCB global brand credit, debit, and prepaid cards as well as Interlink, Star, Nyce, Pulse, Accel, and other domestic-only PIN-based debit card transactions handled by the five largest U.S. owners of portfolios of merchant card processing contracts totaled 69.71 billion last year, up 7.7% over 2014. First Data, Vantiv, Chase Commerce Solutions, Bank of America, and Heartland ranked as the top five U.S. acquirers in 2015 based on transactions handled, positions they have held since 2012. Based on card purchase volume (sp...