Two lawsuits with potentially massive consequences.

Buffalo-based M&T Bank is suing Deutsche Bank for $82 million, claiming for $82 million, claiming Deutsche Bank fraudulently sold M&T high-risk collateralized debt obligations linked to subprime loans. M&T has accused Deutsche Bank of intentionally withholding material information about quality and default problems with the CDOs that would have led to downgrades by rating agencies.

This case is potentially significant because it's the first of its kind involving two large banking companies since the unraveling of CDOs came to light last year. And if it does go to trial, the ruling could set a precedent as there aren't many meaningful decisions in this area. And that could open the floodgates to other lawsuits, particularly with market rumors proliferating about imminent liquidity problems in one or more large investment banks.

Still, there is one thing that troubles me about this case. M&T will have to show concrete examples of Deutsche Bank's failing to disclose information that the agencies would have needed to rate the CDOs accurately. But M&T is a professional investor and it would also have to rebut arguments that it was not aware of the risk involved in such an investment. That in itself would make it a fascinating case.

The second lawsuit sees thousands of retail investors suing Deloitte & Touche and Grant Thornton and banks including Citigroup for tens of millions of euros in damages over the Parmalat collapse. Parmalat filed for bankruptcy on Christmas Eve of 2003. Five years later, it's clear this case still has plenty of legs.