Which U.S. investment bank failed in September 2008 during the global financial crisis?

Lehman Brothers failed in September 2008 during the global financial crisis.

Lehman Brothers filed for bankruptcy on September 15, 2008, in the largest bankruptcy filing in U.S. history at that time. The firm had built extensive exposure to mortgages and mortgage-related securities, especially after the expansion of the U.S. housing market and subprime lending.

Its collapse intensified fear throughout global financial markets. Banks became reluctant to lend to one another, credit markets froze, and stock prices fell sharply. The failure followed the earlier rescue of Bear Stearns and occurred just before the U.S. government’s rescue of American International Group.

Lehman Brothers was not itself a stock-market crash, but its failure became one of the most important triggers of the 2008 market collapse. The Dow Jones Industrial Average fell more than 500 points on September 15, and the crisis continued into early 2009.