Citadel Investment Group filed a claim with the US bankruptcy court seeking to recover as much as $470.5m that the hedge fund believes it is owed from derivatives contracts tied to Lehman Brothers Holdings before its collapse, reports the WSJ. The amount represents the value of the derivatives contracts, and also, costs Citadel says it incurred to replace trades terminated as a result of Lehman’s collapse. It was not known how much the derivatives alone were worth.