By John O'Donnell and Tom Sims

FRANKFURT (Reuters) - There are "lots of indications" that some managers discussed "the reputational risks" of Deutsche Bank's involvement in a share-trading scheme that is the subject of Germany's biggest post-war fraud investigation, according to a conclusion in one of five internal audits seen by Reuters.

The bank issued tax certificates for withholding tax that had never been deducted and made loans to clients to allow them to participate in the scheme to claim tax rebates, according to the audits.

German prosecutors say the scheme's participants misled the government into thinking a stock had multiple owners on its dividend payday who were each owed a dividend and a tax credit, according to court documents.

The authorities say the scheme, called "cum-ex" and involving several other global banks, cost the state 5.6 billion euros in rebates that should not have been paid.

Deutsche Bank commissioned law firm Freshfields to write the five audits as part of an internal investigation into its role in cum-ex trading between 2006 and 2011. They are dated from 2013 to 2015 and marked "highly confidential".

The audits were prepared by Freshfields in Germany and London. One of the five documents is a summary that was handed to the prosecutors in May 2017. Reuters does not know whether the Freshfields documents are the final versions, but prosecutors have been given the summary for use in their investigation, according to a letter sent to the chief prosecutor, seen by Reuters. A spokesman for Freshfields declined to answer any questions for this story.

One part of the audit addresses Deutsche Bank’s decision to lend money to companies – what the audit calls "provision of finance" -- so that those companies could carry out cum-ex trades and the discussion of risks to its reputation.

"Even though evidence is not clear-cut, there are a lot of indications that the staff of SETG (Strategic Equities Transactions Group) and managers, who were responsible for Prime Brokerage at the SEF-IM (Structured Equity Finance — Inventory Management) trading desk, discussed the reputational risk for Deutsche Bank from its provision of finance in January 2009 and came to the conclusion that this was acceptable," one of the Freshfields audits said.

"Group Tax confirmed in March 2009 the provision of leverage for cum-ex trades through Deutsche Bank."

A Deutsche Bank spokesman said that Deutsche Bank was involved in some of its clients' cum-ex transactions and that it was fully cooperating with investigators.

Reuters has seen the Freshfields documents, as well as thousands of pages of bank files, correspondence and court documents relating to the cum-ex case. The documents were obtained as part of a European media investigation coordinated by non-profit newsroom Correctiv.

The audit dated April 16, 2015 pointed to "significant failings" in overseeing two traders, Simon Pearson and Joe Penna, who they say acted as middle men between the clients and the bank departments that lent money to fund the cum-ex scheme and issued tax certificates.

Pearson and Penna have been suspects in the investigation since at least 2014 for their role in cum-ex trading, according to court documents. The Freshfields audits say the two traders were aware the prime brokerage services were being used to help other companies carry out cum-ex deals.

The reports highlighted the role of the traders but also pointed to failures of the bank's internal controls as well as lapses of "managers" in the global financial markets division.

The April 16 report said that the bank’s controls over the trading desk headed by Pearson were too weak and this was a “serious shortcoming”.

That criticism about oversight is leveled at management generally but it does briefly single out one individual.

“Richard Carson was most directly responsible for this shortcoming as the direct supervisor of the manager of the trading desk,” the report said.

Carson has since left Deutsche Bank. In an email to Reuters he said: "I have not seen, nor have been provided with any copies of the reports you mention in your communication. I would not accept that there was any failings on my part." The report did not implicate him further in the cum-ex scheme.

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