The U.S. government is continuing its exit from the insurance giant it bailed out at the height of the financial crisis, American International Group, Inc. (AIG), with a planned US$18 billion common stock offering.

AIG said Sunday that the Treasury Department is selling $18 billion worth of its common shares to institutional investors.

AIG has indicated that it intends to purchase up to US$5 billion of the offering at the initial public offering price.

Back in August, Treasury sold about approximately US$5.75 billion of AIG stock, cutting its stake from 61% to approximately 53%. This latest sale would take its stake down from a majority position to around 20%.

The Treasury will also grant the underwriters in the offering a 30-day option to purchase up to an additional US$2.7 billion in common stock to cover over-allotments.

RBC Capital Markets, LLC is serving as a joint book-runner for the offering, along with Wall Street heavyweights, Merrill Lynch, Pierce, Fenner & Smith Inc., Barclays Capital Inc., Morgan Stanley & Co. LLC, UBS Securities LLC, Wells Fargo Securities, LLC, Credit Suisse Securities (USA) LLC, and Macquarie Capital (USA) Inc.

Citigroup, Deutsche Bank Securities Inc., Goldman, Sachs & Co., and J.P. Morgan Securities LLC have been retained as joint global coordinators for the deal.