Fifth Third Bancorp (FITB) has agreed to purchase Dallas-based Comerica (CMA) for $10.9 billion, the regional banks said Monday. Pending regulatory approval, executives for Fifth Third and Comerica expect the deal to close at the end of the first quarter of next year, creating one of the nation's largest US commercial banks with$288 billion in total assets. The all-stock transaction is aimed at helping Midwest lender Fifth Third, based in Cincinnati, compete against the nation's mega banks as it seeks t ...