JPMorgan has returned $600 million of MF Global money: WSJ Fri Jun 1, 2012 10:55pm EDT (Reuters) - JPMorgan Chase & Co (JPM.N) has returned about $600 million that was at the bank when MF Global Holdings Ltd (MFGLQ.PK) went bust in October, the Wall Street Journal reported late on Friday citing people familiar with the matter. MG Global's bankruptcy trustee James Giddens might have additional claims against JPMorgan for several hundred million dollars, the business daily said. JPMorgan officials contend that the bank no longer holds any MF Global money, the Journal said citing the people. A JPMorgan spokeswoman was unavailable for comment outside regular business hours. Reporting by Abhiram Nandakumar in Bangalore, Editing by Jonathan Thatcher