The Federal Housing Finance Agency, which oversees Fannie Mae and Freddie Mac, is filing lawsuits against large banks that allegedly misrepresented mortgage securities sold during the housing bubble.

The suits target more than a dozen banks, including Bank of America, Deutsche Bank, Goldman Sachs and JP Morgan Chase. The agency is accusing the banks of neglecting to perform the due diligence required under securities law when they marketed mortgage securities to investors, and they overlooked indications that borrowers’ incomes were inflated or inaccurate. The oversight led to borrowers being unable to pay their mortgages, which devalued the securities backing the mortgages.

The lawsuits are unique because they seek billions of dollars in reimbursement for losses rather than an order that the banks buy back the original loans, which other private holders of mortgage securities have already tried to do.

Read more about litigation against banks in the New York Times.