Four bankers who helped a close friend of Russian President Vladimir Putin move millions of francs through Swiss bank accounts have been convicted of lacking diligence in financial transactions.

The four were found guilty on Thursday of helping Sergey Roldugin, a concert cellist who has been dubbed “Putin’s wallet” by the Swiss government.

The executives – three Russians and one Swiss – helped Roldugin, who is godfather to Putin’s eldest daughter Maria, deposit millions of francs in Swiss bank accounts between 2014 and 2016.

The men, who cannot be identified under Swiss reporting restrictions, were found guilty at a hearing at Zurich District Court and were given suspended fines.

The case highlights how people like Roldugin were used as “strawmen”, the indictment seen by Reuters said, a way to hide the true owners of money.

In Switzerland, banks are obliged to reject or terminate business relationships if there are doubts about the identity of the contracting party.

The four executives helped Roldugin operate two bank accounts at Gazprombank in Zurich, through which millions of francs flowed, without conducting sufficient checks, the court heard.

The prosecution had alleged the men failed to do enough to determine the identity of the real owner of the funds and it was implausible that Roldugin could be the real owner.

Sums of around CHF30 million ($32.8 million) were involved in the case, said public prosecutor Jan Hoffmann.

This was despite the musician, who appears on Switzerland’s list of sanctioned Russians, having no listed activity as a businessman.

At the time, the musician told the New York Times that he was certainly not a businessman and did not himself own millions, according to the indictment.

Roldugin was among scores of members of Putin’s inner circle sanctioned by the West, including Switzerland, after Russia invaded Ukraine in 2022.