The largest merchant acquirer worldwide, Worldpay, and a processor with assets in support services for merchant acquiring and card issuing, Network International, were both purchased in multibillion-dollar deals this month involving private equity firms. GTCR will purchase 55% of Worldpay. Brookfield Asset Management will purchase 100% of Network International.   US-based GTCR will pay $11.70 billion to take control of Worldpay from current owner Fidelity National Information Services (FIS), and possibly another $1.00 billion if the merchant business meets performance goals. The dea...