Mortgage insurance has often gotten piggybac:/c/a//19/BUUPS9DQ6.DTL

The details: If you buy a house with less than 20 percent down, your lender might require you to buy mortgage insurance. Fannie Mae and Freddie Mac generally won’t buy mortgages that exceed 80 percent of the home’s value without insurance. Some lenders require insurance on loans they can’t sell to Fannie and Freddie, such as jumbo loans, to protect themselves.

If you default on your loan and the sale of your home doesn’t cover your loan balance, the insurance company will pay the mortgage holder all or part of the loss. Seven companies - PMI Group, Radian Group, MGIC Investment, Triad Guaranty and subsidiaries of American International Group, Genworth Financial and Old Republic International - account for more than 95 percent of the U.S. private mortgage insurance market.

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