First Republic Bank has contributed at least 21.3 percent of the loans that have been included in jumbo mortgage-backed securities issued in the first nine months of this year, according to a new ranking and analysis by Inside Nonconforming Markets. The bank was identified as having contributed $2.18 billion into jumbo MBS issued in the first three quarters of 2015, including $619.19 million in the third quarter. First Republic’s contributions to jumbo MBS issued in the third quarter alone topped the contributions of any other lender in the first nine months of the year. Jumbo MBS issuers and rating services generally disclose...[Includes two data tables]