The Government Accountability Office Tuesday issued a new estimate of the deal that bailed out the insurance giant.
The Treasury said recently it would put $5 billion worth of AIG shares on the market.
The sale, when complete, will have the government still holding $40 billion in AIG stock, $31 billion being held by the Treasury and $9 billion at the Federal Reserve.
At this point, "when all the assistance is considered, the amount the federal government ultimately takes in could exceed the total support extended to AIG by more than $15.1 billion," the GAO said.
The estimate could change, depending on the price of AIG stock and other market factors in the future. The new estimate also "does not include estimates of subsidy costs associated with the assistance," the GAO said.