If I were the kind of blogger to say I told you so -- which I definitely am -- I'd remind you that last week, when the prolific securitization trustee U.S. Bank filed a second suit demanding that a mortgage-backed securities issuer buy-back deficient underlying mortgage loans, I predicted that this was the beginning of a trend. Trustees are under serious pressure both from regulators fed up with their chronic reluctance to assert put-back demands against MBS sponsors and from MBS investors running out of time on securities claims. If their duties as trustees are anything short of a joke, they have to begin to take action.

On Wednesday, my prediction of a trend got a little more support. Wells Fargo filed a Delaware Chancery Court suit against EMC Mortgage, the erstwhile Bear Stearns mortgage-lending unit, demanding that EMC buy back more than 800 mortgages that breach the representations EMC made about them. Wells is suing in its capacity as trustee of a Bear Stearns MBS offering in which three-quarters of the 2000 underlying loans, according to the complaint, are deficient.

The put-back suit comes seven months after Wells sued EMC (now part of JPMorgan Chase) to obtain information about those underlying mortgage loans. As Wells Fargo said in that January 2011 Delaware Chancery Court complaint, it was under pressure from a Bear Stearns MBS noteholder who held 42 percent of the certificates in the trust. (The noteholder, who has not been identified, is represented by David Grais of Grais & Ellsworth.) Wednesday's suit asserts that Wells Fargo's analysis of the loan documentation it received via the January case reveals rampant misrepresentations about the underlying mortgages.

One other interesting aspect of the new Wells filing: As it was in the January suit, the bank is represented by Ropes & Gray and Abrams & Bayliss. Ropes & Gray's involvement is notable; law firms with robust corporate practices usually avoid suing banks, even on behalf of other banks. That's why litigation-centric firms like Quinn Emanuel Urquhart & Sullivan and Kasowitz Benson Torres & Friedman have been able to carve out a lucrative specialty in cases against banks.

Lawyers at Abrams and Ropes referred me to a Wells Fargo spokeswoman, who said that this is the largest put-back case the bank has filed, and that it was brought at the direction of investors in the trust. She declined comment on Ropes's involvement.

I left messages with Daniel Rath of Landis Rath & Cobb, who represented EMC in the earlier Wells suit, and with Stacey Friedman of Sullivan & Cromwell, who's representing JPMorgan in Ambac's blistering MBS case against EMC. Neither got back to me.

(Reporting by Alison Frankel)

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