Swiss bank UBS has revealed that the authorities in the United States are investigating securities that it sold to wealthy clients which may violate US tax law.
The probe is focused on so-called ‘bearer bonds’ which can be transferred without registering ownership, enabling the buyers to potentially hide assets.
The bank said it was cooperating with investigators.
The revelation was in its latest profit report which showed UBS paid out around one billion euros last year to US, British, Swiss and German regulators to settle various scandals.
They included alleged manipulation of foreign exchange rates and claims it helped rich German clients dodge taxes.
This comes as the authorities in several countries are looking into reports that HSBC’s Swiss arm helped wealthy customers avoid tax.
UBS’s shares fell on Tuesday as along with the released of its latest earnings, the group warned over the impact of the surging Swiss franc and negative interest rates in Switzerland and the eurozone.
Switzerland’s biggest bank said a sudden move by the central bank to abandon a cap on the franc, which sent the currency surging and is set to make life difficult for Swiss financial firms and exporters, will take a toll.