Deutsche Bank has raised its forecast for bad loans against the backdrop of a weak German economy, as the bank returned to profit in the third quarter, boosted by investment banking and a cut in reserves for Postbank lawsuits.

Germany's biggest lender Deutsche Bank on Wednesday reported a sharp jump in third-quarter profits, boosted by the settlement of investor lawsuits related to a troubled takeover.

Deutsche Bank on Wednesday beat expectation in its return to profit in the three months to September, after snapping its 15-quarter profit streak in the second quarter.   Net profit attributable to shareholders came in at 1.