American International Group
A source familiar with the insurer's financial position had said on Wednesday that AIG would report a loss of about $5 billion.
AIG's first-quarter loss was equal to about $1.98 per share, according to a company statement issued after U.S. markets closed on Thursday, compared with a $7.81 billion loss in the same period a year ago.
AIG had a $61.7 billion loss in the fourth quarter, the largest quarterly loss in corporate history.
AIG shares, which closed up 6 percent at $1.95 in the regular session on Thursday, were down almost 5 percent after the report. In the last year the shares have traded between 33 cents and $48.65, according to Reuters data.
(Reporting by Lilla Zuill)