PARIS (Reuters) - Convicted French rogue trader Jerome Kerviel launched a new legal salvo against his former bank, Societe Generale <SOGN.PA>, accusing it of fraud and demanding that an independent expert examine how much money was lost in France's biggest-ever trading scandal.
Kerviel filed a civil lawsuit against the bank in Paris on Thursday, a week after an employment tribunal rejected his plea for a new expert inquiry to help overturn his dismissal.
Kerviel received a three-year prison sentence for unauthorized trades that caused losses put by SocGen at 4.9 billion euros ($6.4 billion), but is not in jail because he is waiting for the result of a final appeal.
The rogue-trading scandal, which hit as the global financial crisis began to unfold in early 2008, became a rallying point for critics of the banking system, and far-left groups and the press have painted Kerviel as a victim of big finance.
The ex-trader maintains his bosses were aware of the trades, and argues in the new lawsuit that SocGen amplified the losses by unwinding positions held by three other traders.
"No legal expert has ever validated Societe Generale's alleged losses," Kerviel's lawyer, David Koubbi, said in a statement. "It is now imperative that the court order an independent review that brings to light Societe Generale's dealings, which do not conform to its status as victim."
Koubbi said the 4.9 billion euros the bank says it lost was a "fictitiously built" sum.
SocGen declined to comment.
($1 = 0.7668 euros)
(Reporting by Alexandria Sage; Editing by Mark Trevelyan)