These suits have caused courts in some jurisdictions to require that the true owner of the mortgages do the foreclosing, not MERS. In some cases, these suits cause a delay in foreclosure proceedings -- but no one yet has gotten a house back because of a MERS issue.

Class action lawsuits have had little success

While an online search turns up plenty of class action filings, they have mostly been dismissed or are not yet resolved. Experts attribute this overall lack of big class action success in the courts thus far to the fact that the plaintiffs bring rather basic claims, such as "I made my trial payments on time, and I still have not been approved for a loan modification."

Individual cases have had more success

That said, the HAMP and foreclosure lawsuits that have been successful are exactly those kinds of claims -- brought by individual homeowners alleging bad faith by lenders in courts all across the country -- from U.S. Bank National Association v. Alejandra Padilla in New York, to the small claims case in Big Bear City, Calif., in which homeowner Dave Graham successfully sued Bank of America all by himself.

How to win a foreclosure or modification battle in court

Storm Bradford, of Mortgage Fraud Examiners, says if you are trying to get a mortgage modification or avoid foreclosure, you can make your own luck. Before going hat in hand to your lender, he advises, get a high-quality forensic evaluation of your mortgage. Irregularities in the loan-origination process are common, particularly in the appraisal. Discovering these irregularities puts you in a much better position to negotiate out of your mortgage difficulties.

"Nothing works like the lawsuit or the threat of a lawsuit" when dealing with a mortgage lender, he says. Want proof? "Check the language of a modification agreement -- they always put an indemnity clause in there that keeps you from going after them if you discover something illegal or fraudulent -- because there are things that are wrong in there, and they know it."

Beware of class-action scams

The Better Business Bureau is warning homeowners to be aware of the latest scam, designed to get you to pay upfront mortgage assistance costs of as much as $5,000. This foreclosure and modification "help" is masking itself as the nationwide mass joinder lawsuit against mortgage companies.

Homeowners receive letters promising a loan modification, foreclosure stoppage, cash settlement, lien stripping, or even free and clear title. Do not fall for this -- it is merely a way for firms to get around the laws prohibiting the collection of upfront fees for mortgage modification help.

Talk to a lawyer

"I regularly meet clients who have been repeatedly denied mortgage modification requests and are faced with foreclosure lawsuits initiated against them by their mortgage companies," says New Jersey attorney David Giller. "Most of these homeowners don't realize that a qualified attorney can help them in many ways."

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Have you considered bankruptcy?

One final available weapon is a bankruptcy filing. "Although most homeowners are afraid of filing for bankruptcy, there are many solutions available through the bankruptcy laws which are not available in foreclosure defense," Giller says. "These solutions help get the clients the mortgage modification they desperately sought from their mortgage company in a far more efficient manner."

This article was reported by Gina Pogol for HSH.com.