While banks have plenty of capacity to retain jumbo mortgages in portfolio, the top two contributors to jumbo mortgage-backed securities issued in the second quarter of 2014 were actually banks, according to a new ranking and analysis by Inside Nonconforming Markets. First Republic Bank and JPMorgan Chase were the top two contributors to the scant four jumbo MBS during the quarter. And since the start of 2013, three of the top five ... [Includes one data chart]