Lehman Brothers' bankruptcy on September 15, 2008, became a major milestone of the 2008 financial crisis.
Lehman Brothers was the fourth-largest investment bank in the United States when it filed for Chapter 11 bankruptcy protection. The filing followed heavy losses connected to mortgage-related assets and the collapse of the American housing market. Its failure disrupted confidence in financial institutions and contributed to severe stress in credit markets worldwide.
The bankruptcy is often described as the largest in U.S. history by assets at the time, although bankruptcy rankings can differ depending on whether they use assets, liabilities, or inflation-adjusted measures. Bear Stearns had been rescued earlier in 2008, while Merrill Lynch was acquired by Bank of America. Those events are related but are not the same answer.