The U.S. Treasury Department and American International Group (NYSE: AIG) sold 300 million shares of the company yesterday at $29 each, raising $8.7 billion in a secondary offering, as part of the plan to divest the U.S. government’s 92% stake in the company.Treasury sold 200 million shares, receiving $5.8 billion and lowering their stake in the company to 77%, while AIG sold the remaining 100 million shares, raising $2.9 billion.The Treasury eked out a $54 million profit. The government's average cost per share is $28.73, so any price above that means they turn a profit on their investment.Timothy F. Geithner, the Treasury secretary said, ""Today's announcement represents an important milestone as we continue to exit our stake in A.I.G. and wind down TARP.""At one point, it was speculated the offering might raise over $20 billion, but AIG's stock has slumped enormously this year, trading down more than 50% from its 52-week high set in January at $62.87 per share.