Losses widened at Société Générale Corporate & Investment Banking in the third quarter as the collapse of Lehman Brothers and writedowns on monolines, exotic credit derivatives and asset-backed securities took their toll and wiped more than €1bn ($1.3bn) off revenues.

Société Générale's corporate and investment bank posted a €244m net loss in the three months to September. The loss compares with a €310m profit in the third quarter last year and a €186m loss in the second quarter this year.