Banks and thrifts appear to be replenishing their first lien portfolio holdings while not taking on major amounts of new servicing, according to the Inside Mortgage Finance Bank Mortgage Database. Banks and thrifts held $1.70 trillion in first-liens in portfolio at the end of the second quarter of 2011, up 0.2 percent from the previous quarter.Portfolio holdings were down 0.9 percent compared with the second quarter of 2010. Bank portfolios are largely being used to hold mortgages that meet underwriting guidelines for the government-sponsored enterprises ... [includes one data chart]