1, the important reason is that the CDO plummeted, which caused a loophole of1500 million dollars for Lehman Brothers. From where? In a sense, deep participation in the synthesis of CDO (debt-backed bonds) and CDS (credit default swap contracts) markets is probably one of the direct reasons for Lehman's collapse.

No one from the government or other large enterprises came to help. On September 15, 2008, Lehman Brothers, the fourth largest investment bank in the United States, finally abandoned its helmet and armor and declared bankruptcy protection.

If you want to know the details of this part, you can watch the documentaries "The Bank that Destroyed the World" and "Too Big to Fail". And the BBC TV series The Last Days of Lehman Brothers.

Extended data:

Why didn't the US government save Lehman Brothers?

Lehman is a private enterprise. The US government used taxpayers' money to save the stock market, Bear Stearns and Fannie and Freddie, which caused strong dissatisfaction among many members of Congress and even caused widespread public criticism.

In addition, from the actual situation, Lehman Brothers is by no means the last financial institution that needs rescue. If you shoot again, it is likely to "pull" the US government's finances into the water. If we want to prevent the financial crisis from expanding further and save the financial enterprises that are already in trouble, the government cannot but consider the road of marketization.

References:

Lehman Time-Baidu Encyclopedia

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