Deutsche Bank, Germany’s largest lender, reported a surprise net loss of 2.2 billion euros ($3 billion) for the fourth quarter of 2012 on Thursday, hurt by the diminished value of some assets as well as costs related to numerous legal proceedings.

The results underline the task ahead for Jürgen Fitschen and Anshu Jain, the co- chief executives who took over the bank less than seven months ago and have declared their intention to deal more severely with the legacy of the financial crisis.