The offices of a Deutsche Börse AG subsidiary are being searched as part of a cum-ex probe, Reuters reported, citing prosecutors in the German city of Cologne.
The stock exchange operator's Luxembourg-based unit Clearstream Banking SA was the focus of the operation, a spokesman told Reuters.
The raid is part of investigations into a dividend-stripping technique known as cum-ex deals, which involve trading shares rapidly to create the impression of numerous owners who are each entitled to tax refunds.
Deutsche Börse said it is cooperating with authorities.
German newspaper Handelsblatt first reported the news.
