Jérôme Kerviel, the rogue trader who lost almost €5 billion (£3.8 billion) through unauthorised bets on the stock market, was granted bail yesterday in a move likely to enhance his reputation as a French folk hero.

The junior trader was greeted by rows of cameras and microphones as he left the infamous Santé prison in Paris, where he had been on remand for 37 days. He was accorded the rare privilege of his own cell in the jail's “VIP” wing. Wearing a dark suit and a pink shirt, the operator at the centre of the biggest rogue trader scandal in history refused to answer questions as he got into a car with Elisabeth Meyer, his lawyer.

“He was shocked when I told him that he was coming out,” she said. “He wasn't expecting it and he needed a little time to take it in. But was very pleased. He is going home to rest.”

Mr Kerviel was freed by the Paris Appeal Court under a ruling that represented a setback to the French authorities and to Société Générale, the bank that employed him as a derivatives operator. Both had pressed judges to keep him in prison, officially to stop him from concerting with potential accomplices or tampering with evidence, unofficially to prevent him from courting publicity.

Rogue traders' profit boosted SocGen bonuses

Jerome Kerviel's lawyer claims executives at the French bank benefited from the successful investments of the rogue trader

• SocGen rights issue will be at a 39% discount

• SocGen trader remanded in custody after court hearing

Multimedia

• Full coverage of the SocGen scandal

• Blog: Charles Bremner on SocGen

• Video: Patrick Hosking on the impact of fraud

Background

• Who Knew What and When?

• SocGen director probed over €100m share sale

• Ex-SocGen risk auditor calls systems a sham

Related Links

• SocGen trader Kerviel in court plea

• SocGen missed 75 warnings on trader Kerviel

Multimedia

• Full coverage of the SocGen scandal

Appeal Court judges said that there was no evidence of an accomplice and little chance of him destroying the record of his transactions on the bank's computer system.

Mr Kerviel's case was also boosted when he was promised a job by a computer expert who is an acquaintance of Maître Meyer. The 31-year-old trader was told to comply with strict bail conditions, which included a ban on leaving the Paris region or on working in finance. He must also report to a police station once a week.

Mr Kerviel became France's most famous inmate when he was remanded in custody last month on charges of breach of trust, fabricating documents and illegally accessing computers.

He is alleged to have staked €50 billion of his bank's money on futures markets in an attempt to transform his career and earn multimillion-euro bonuses. His bets far exceeded authorised levels. The overall ceiling for the desk on which he worked was €125 million. SocGen, the second-biggest French bank, emerged from the scandal with a loss of €4.9 billion.

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