Wells Fargo and JPMorgan Chase account for the vast majority of bank holdings of negative amortization mortgages, according to a new ranking and analysis by Inside Nonconforming Markets. Bank exposure to negative amortization mortgages continues to dwindle as originations of such loans largely stopped after the financial crisis. Large chunks of the holdings at Wells and Chase are due to acquisitions of Wachovia and Washington Mutual, respectively ... [Includes one data chart]