First Republic Bank was the top contributor to jumbo MBS issued in 2014, according to a new ranking and analysis by Inside Nonconforming Markets. Officials at First Republic note that the bank tends to sell its originations of fixed-rate mortgages while adjustable-rate mortgages make for better portfolio holdings. However, the secondary market bid was strong enough for First Republic to sell some jumbo ARMs during the year, including a ... [Includes one data chart]