By John O'Donnell
BONN (Reuters) - A British banker charged with fraud in Germany has agreed to reveal the workings of a share trading scheme which prosecutors allege cost the country 450 million euros (1 million) in lost taxes, his lawyer said on Wednesday.
In a breakthrough for Germany's biggest fraud inquiry, Hellen Schilling, a lawyer acting for one of two defendants in the case, said Martin Shields had already made a significant contribution in explaining the scheme to prosecutors.
The trial is the first in a wider investigation aimed at recovering billions from banks who profited from a scheme described by finance minister Olaf Scholz as a 'scandal' which Germany estimates cost it more than 5 billion euros.
Prosecutors in Germany allege that players in the so-called cum-ex scheme misled the state into thinking a stock had multiple owners who were each owed a dividend and a tax credit.
German state prosecutor Anne Brorhilker earlier outlined criminal charges against Shields and fellow British banker Nicholas Diable, who she said organized a network of traders and lenders to make double tax reclaims with sham share trades.
"Mr. Shields is the first (to be put on trial) but he is not the only one and he is not the central figure in cum-ex," Schilling told judges, adding that the 41-year-old banker's evidence would make it easier to accelerate the case.
Diable, 38, declined to make a statement to court. His lawyer did not respond to a request from Reuters for comment.
Neither of the defendants is required to enter an immediate plea, according to usual German court proceedings but will launch their defense in the coming weeks.
The alleged scheme involved trading shares rapidly around a syndicate of banks, investors and hedge funds to give the impression of numerous owners, each entitled to a tax rebate.
Brorhilker alleged the two men, who face a possible jail term and a state order to repay any profits they made, were involved in organizing sham share trades in companies including carmaker BMW and airline Lufthansa between 2006 and 2011.
Brorhilker described how the two had started when working at German bank HVB, before moving to a small investment firm, tapping a wide network of contacts to arrange the trades, sometimes splitting the profit made with banks involved.
She outlined more than 30 instances of double-tax reclaims totaling 447 million euros and involving banks including Germany's Warburg Group, BNY Mellon and Societe Generale (PA:SOGN).
Those banks have also been included in the German court trial and may have to repay any profit made from the schemes.
A spokesman for Warburg said that it had not received such multiple tax rebates and had never set out to do so, while Societe Generale and BNY Mellon declined to comment.
A spokeswoman for HVB, which has blamed its involvement on wrongdoing by individuals, declined further comment.
Germany changed and clarified the law in 2007, 2009 and 2012 to prevent cum-ex trades, but the scam then hit Denmark, where tax authorities say they lost billion in rebates.
The discovery of the trades in Germany and Denmark prompted investigations by other countries, including Austria and Belgium, which have found they were also affected, albeit on a far smaller scale.
