Private equity firms have significantly contributed to the four phases of merger and acquisition activity in the payment card industry over the last 20 years. The initial phase involved buying large processing businesses from banks, and the second, scaling those investments through horizontal deals that involved buying additional processors. Over the last five years, the third M&A phase has been taking shape. It involves adding software specialists, payment gateways and other applications to core transaction processors to create vertically integrated companies. This generates more re...