Deutsche Bank's directors will question the management board over claims the lender failed to recognize billions of euros in unrealized losses during the financial crisis, two sources said.
The supervisory board, which has 20 independent directors "is seeking answers from management", a person familiar with the body said on Friday.
Deutsche Bank has rejected the claims, which resurfaced this week, as unfounded.
The risk committee on the board of directors is set to discuss the matter when it holds a regular meeting before Christmas, another source close to the bank said.
The demand for clarification comes after law firm Labaton Sucharow LLP said Eric Ben-Artzi, a former quantitative risk analyst at Deutsche, used a whistleblower programme to tell the U.S. Securities and Exchange Commission (SEC) the bank failed to report the value of its credit derivatives portfolio correctly from 2007 through 2010.
The topic of valuations will also be discussed at the next full supervisory board meeting in late January, a second person familiar with the supervisory board's thinking said on Friday.
Deutsche Bank declined to comment on whether the supervisory board was demanding answers from management.
The general nature of the allegations about disagreements over valuation of credit derivatives was known and had been discussed by the supervisory board in the past, the second person said.
Supervisory board chairman Paul Achleitner briefed fellow directors and told them the internal investigations of the matter had finished and, for the bank, the case belonged to the past, a third person familiar with the supervisory board's thinking said.
Reports by media including the Financial Times this week alleging the bank failed to recognise up to $12 billion of unrealized losses during the financial crisis raised "some new questions about the magnitude," the first source familiar with the supervisory board's thinking said.
The figure could not be independently verified by Reuters.
The SEC declined to comment.
Deutsche Bank said it was cooperating with the SEC and added that the allegations, which it noted were more than two and a half years old, "have been the subject of a careful and thorough investigation, and they are wholly unfounded."
"Moreover, the investigation revealed that these allegations stem from people without personal knowledge of, or responsibility for, key facts and information," the bank added.
In June 2011, Reuters reported on a Sarbanes-Oxley whistleblower action filed against Deutsche Bank in May 2010 alleging that some of the assets in a derivatives portfolio may have been improperly valued in order to hide trading losses.
In an internal presentation given by Bill Broeksmit, head of risk and capital optimisation at Deutsche Bank in June 2011, Deutsche Bank said it had been able to unwind a large portion of its credit derivatives portfolio without taking heavy losses, a sign that some buyers had broadly accepted Deutsche's view on how to value certain assets.
German politicians have nonetheless called for markets regulator BaFin to investigate the claims and suggested it had not acted forcefully enough on the issue.
BaFin on Friday declined to discuss allegations against Deutsche Bank and rejected suggestions it may have neglected its duties of supervision.
(Reporting by Edward Taylor, Arno Schuetze and Philipp Halstrick, Jonathan Gould; Editing by Helen Massy-Beresford)
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