The infringements at issue are related to the government-sponsored enterprise's financial troubles, exposed last year, which lead to a $4.4-billion restatement of earnings brought on by questionable internal accounting practices. The revelation resulted in the dismissal and resignation of a handful of top players at the company; former chairman and CEO Leland C. Brendsel, and former president and COO David Glenn both had to be replaced.

In December, Freddie Mac signed off on a consent order with the US Office of Federal Housing Enterprise Oversight that compelled it to pay a $125-million fine related to the misstated earnings that covered the years 2000 to 2002. As for its latest legal woe, the ball is now in Freddie Mac's corner.

"Freddie Mac has been cooperating with the SEC's investigation and will continue to do so as we evaluate the manner in which we will respond to the receipt of the Wells Notice," the company says in a prepared statement. Actually, Freddie Mac is not obliged to respond to the notice, but its history of cooperation with the SEC indicates that it will.