Banks have been retaining recent originations of jumbo mortgages in portfolio while selling vintage mortgage servicing rights to nonbanks or entering into subservicing agreements. And with the rise in interest rates, banks have increased their appetite for adjustable-rate mortgages. Banks held $1.76 trillion in first liens in portfolio as of the end of the second quarter of 2013, down only 0.1 percent from the second quarter of last year, according to a new ranking and analysis ... [Includes one data chart]