American International Group (AIG), American multinational insurance corporation whose potential bankruptcy in 2008 led to the largest federal bailout of a private company. AIG was founded as American Asiatic Underwriters by Cornelius Vander Starr in 1919 in Shanghai, China; it soon expanded internationally and became known as American International Underwriters. With the advance of Mao Zedong's Red Army on Shanghai in 1949, Starr moved the headquarters to New York. In 1962 Maurice R. "Hank" Greenberg took over leadership of the company (until he was forced out as chief executive in 2005 because of transactions that created overstated earnings reports) and expanded it by buying up numerous insurance and other financial firms. The company, which assumed its present name in 1967, became one of the largest insurance companies in the world. In the 2000s, however, AIG incurred huge losses relating to subprime home mortgages, both its own and those of other companies and banks it had insured against losses on mortgage-backed securities, although many AIG businesses remained profitable.

By 2008 bankruptcy loomed due to a downgraded credit rating and increased calls for collateral required by the insurance on the mortgage-backed securites. The Federal Reserve Bank, concerned over potentially far-reaching repercussions to the international financial system should AIG fail, agreed to give AIG a line of credit for up to $85 billion in exchange for 80% of its stock, effectivily nationalizing the company. Eventually the Federal Reserve Bank and U.S. government increased their potential support to more than $182 billion through investment and credit lines and by buying mortgage-backed securities. The Treasury Dept. ultimately owned more than 90% of AIG before beginning to sell off shares in 2011. AIG sold a number of its profitable assets in order to pay back the U.S. government, and recovered from its near collapse in 2009. The bailout became controversial because large bonuses were paid to many AIG employees after the bailout (though these were largely later returned) and because some of the financial firms, such as Goldman Sachs, that benefited from the financial stability the bailout was designed to preserve also received sizable payments from AIG after the bailout. Goldman Sachs was also accused by some at AIG of having misled AIG over the quality of the mortgage-backed securities that AIG insured. In 2011 Greenberg brought a class-action lawsuit for damages against the government, contending it had exceeded its authority in demanding its stock in return for aid. The 2015 verdict said the government had had no right to demand the ownership control of AIG, but did not award damages because the company would have become bankrupt without the government aid.