PMI Group Inc.’s (PMI) U.S. mortgage insurance unit sold its equity ownership in troubled bond insurer FGIC Corp. for an undisclosed amount.

The sale, for what the mortgage insurer called an insignificant amount, could allow the unit to realize tax benefits. However, the ability to recognize those benefits depends on estimated future taxable income at the end of future financial reporting periods.

PMI wrote down its investment in FGIC, the holding company of Financial Guaranty Insurance Co., in the first quarter of 2008 so it didn’t recognize any losses from it in 2009 or 2010.

PMI reported its 12th consecutive quarterly loss Thursday, even as the number of defaulting homeowners on its books dropped.

Losses have been par for the course for mortgage insurers during much of the past three years. The coverage they sell protects lenders when homeowners default, and those homeowners have defaulted at record rates as home prices crashed and unemployment soared. But last week, larger rival MGIC Investment Corp. (MTG) reported its first profit in almost three years.

PMI’s shares closed at $3.13 Friday and were inactive after hours.