A group of institutional investors – including BlackRock and Pacific Investment Management Co. – filed suit this week against six banks for their alleged failure as mortgage-bond trustees for over $2 trillion worth of mortgage securities. The suits against the banks – U.S. Bancorp, Citigroup, Deutsche Bank, The Bank of New York Mellon, HSBC Holdings, and Wells Fargo – were filed in New York State Supreme Court, New York County. The plaintiffs seek unspecified damages for losses exceeding $250 billion on nearly 2,220 non-agency MBS trusts issued between 2004 and 2008. The suits allege...