A Paris court sentenced former Société Générale trader Jérôme Kerviel to three years in prison for his role in one of the largest trading scandals in history and ordered him to repay the $6.69 billion loss suffered by the French bank.

The Wall Street Journal reports the verdict lays the entire blame of the January 2008 trading debacle on the 33-year-old, dismissing his argument that SocGen had turned a blind eye to years of unauthorized trades.

Yet SocGen hasn’t escaped sanction; France's banking commission fined the bank €4 million by for not having adequately supervised Kerviel.

"The absence of proper supervision on the part of the bank should not have been interpreted as a tacit green light to engage in wild speculation," Judge Dominique Pauthe told the courtroom before an expressionless Kerviel. In convicting Kerviel of breach of trust, forgery, and unauthorized computer use, the judge also handed Kerviel a lifetime trading ban, according to the Journal.

The shock announcement in January 2008 that SocGen, one of France's two most important banks, had suffered a net loss of €4.9 billion after unwinding a series of bets placed by a low-level trader roiled the financial industry just as it was about to sink into a major crisis.

The paper reports that as the probe got under way, Kerviel immediately acknowledged engaging in years of unauthorized trades, but said he was just trying to make money for the bank. Over the years, Kerviel had been able to defeat multiple layers of control at the bank using apparently simple techniques: He fabricated emails, promised bottles of champagne to back-office supervisors and gave evasive answers when questioned about anomalies in his trading books.

The high-profile case is similar to that of Nick Leeson, a rogue trader whose fraudulent activity caused the collapse of Barings Bank in 1995.