The Société Générale trader, whose "exceptional and massive" fraud wiped almost €5bn ($7.3bn) off the bank's full-year profits, was able to conceal his "colossal" positions thanks to knowledge he gleaned while working in SG's middle and back offices, the bank claimed today. He has been named as Jérôme Kerviel.

Sources close to the bank confirmed the trader's name this afternoon. Kerviel, who turned 31 on January 11, worked in the bank's back office after studying a Masters degree in back and middle office management in Lyon, graduating in 2000. The Masters degree was operated by a body called the Orcofi Association, whose patrners include SG, BNP Paribas, The Bank of New York and State Street.