The Paris appeals court has ordered former Societe Generale trader Jerome Kerviel to spend three years in prison and pay back a staggering 4.9 billion euro ($6.25 billion) in damages for one of the biggest trading frauds in history.

The 35-year-old Kerviel, who never profited personally from his unauthorised trades, says he was a scapegoat for the bank and a victim of a financial system that runs on greed and profits. His lawyer David Koubbi called the verdict "absolutely lamentable" and said his team will consider taking the case to France's highest court.

A lower court convicted Kerviel in October 2010 of forgery, breach of trust and unauthorised computer use for covering up bets worth nearly 50 billion euro in 2007 and 2008. By the time his trades were discovered and made public, he had amassed losses of almost five billion euro on those bets.

The sentence - a five-year prison term, with two years suspended, plus the payback of all the losses he incurred - shocked many in the French public. After a global financial crisis that many blamed on big banks, many believed Kerviel's claim that he was a victim of an unjust system.