U.S. Bank has struck again. Less than a week ago, the bank, acting as securitization trustee, sued Bank of America to demand the repurchase of deficient loans underlying Greenwich Capital MBS offerings. And now U.S. Bank has sued WMC Mortgage and Equifirst Corporation in its role as trustee for a $550 million UBS offering. Here's the 23-page Minnesota federal court complaint, filed by the recently ubiquitous Kasowitz Benson Torres & Friedman. 

There aren't any bombshells in the complaint, which asserts the all-too-familiar allegations that WMC and Equifirst made false representations and warranties about the mortgage loans it supplied UBS. Instead, the news is that U.S. Bank has suddenly adopted a newly activist role as securitization trustee.

Under standard MBS pooling and servicing agreements, remember, the trustee is tabbed with responsibility for demanding that mortgage issuers buy back deficient underlying loans. But securitization trustees-Bank of New York Mellon, Deutsche Bank, and U.S. Bank dominate the market-have been notoriously slow to assert so-called put-back claims on behalf of MBS investors.

U.S. Bank's apparent awakening comes as securitization trustees are under serious scrutiny. New York attorney general Eric Schneiderman and Delaware AG Joseph Biden III are in the midst of an investigation of securitization practices, reportedly looking hard at trustees BNY Mellon and Deutsche Bank. That investigation, which has been a sticking point in mortgage servicing settlement talks between big banks and a larger group of state AGs, has already resulted in the N.Y. AG's state fraud claims against BNY Mellon in the proposed $8.5 billion BofA put-back settlement with Countrywide MBS noteholders.

In last week's suit U.S. Bank is represented by Quinn Emanuel Urquhart & Sullivan, which is similarly sharing the Federal Housing Finance Agency litigation with Kasowitz (Quinn is leading 13 of the cases; Kaswitz has four). The two firms both also represent the bond insurer MBIA in various pieces of litigation related to mortgage-backed securities. Marc Kasowitz and Michael Fay of Kasowitz Benson referred me to U.S. Bank. U.S. Bank spokesman Thomas Joyce acknowledged the suits were filed under the banks' role as trustee, but declined to comment on specifics.

(Reporting by Alison Frankel)

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