The Treasury Department announced last month that it sold all of its remaining shares of AIG after conducting six public offerings of the insurer's stock over 19 months. At the start of the sales, Treasury had owned 92 percent of AIG's outstanding common stock.
The Treasury said Wednesday that the lawsuit was "without merit" and welcomed AIG's decision not to support it.
"The board's decision not to join Starr International's lawsuit is the right result," Timothy G. Massad, Assistant Secretary for Financial Stability, said in a statement. "It is consistent with AIG's determination to rebuild the company, repay taxpayers, and move forward."
In November, AIG reported a third-quarter profit of nearly $2 billion thanks to strength in its insurance operations and investment returns. In the same period a year earlier it lost $4 billion.
AIG stock closed up 11 cents, or 0.3 percent, to $35.76 in Wall Street trading today. The stock has gained more than sixfold since bottoming out at $5.86 in March 2009.
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