German authorities have expanded their investigation into a 2011 lending transaction, doubling the number of Macquarie staff considered suspects since late 2018.
In an update to the ASX on Thursday evening, Macquarie said it was cooperating with an industry-wide investigation into dividend trading in Germany which began in September 2018.
The financial services giant said it had been responding to requests for information from German authorities about its activities in a 2011 short-selling transaction.
The transaction saw it act as a lender to a group of independent investment funds who sought to trade shares around dividend payment dates on an effort to gain the benefit of dividend withholding tax credits.
In 2018 Macquarie said the investors' claims were refused and German revenue was not impacted by the deal.
Originally, German authorities had indicated their desire to interview up to 30 individuals involved in the deal.
However the authorities have since widened their net, with around 60 former and current Macquarie staff - including chief executive Shemara Wikramanayake - recently designated as suspects, according to Macquarie.
The firm said most of the 60 suspects in question are no longer employed by Macquarie, and that no current staff members have been interviewed by authorities so far.
"No information of detail or particularity has been provided regarding the naming of these people other than that it relates to short selling-related activities," Macquarie said in a statement.
"The total amount at issue is not considered to be material and MGL has provided for the matter.