Lehman Brothers Holdings is suing J P Morgan Chase to recover tens of billions of dollars in lost value.
Lehman claims J P Morgan siphoned off billions of dollars of assets in the days leading up to its bankruptcy, the BBC reports.
J P Morgan - Lehman's main short-term lender before the latter's collapse in September 2008 - is accused of contributing to the failure by demanding $US8.6 billion of collateral as credit markets tightened.
It has called the lawsuit ill-conceived.
