The Federal Prosecutor’s Office has opened an investigation into former Swiss National Bank (SNB) chairman Philipp Hildebrand in connection with possible violations of secrecy laws, after receiving an undisclosed complaint.
Hildebrand's current employer, fund management firm BlackRock, said he rejected the allegations.
"Mr Hildebrand absolutely rejects any allegations of wrongdoing and is providing the Attorney General with whatever assistance is necessary to resolve this matter," BlackRock spokesman Marc Bubeck said in an emailed statement to Reuters on Thursday.
The allegations related to a period prior to Hildebrand's joining BlackRock, Bubeck said.
"[It] involves a complaint regarding violation of federal secrecy law brought by a private person in July 2012."
Bubeck said Hildebrand, who has moved to London since resigning from the SNB last year, was not available to comment further on the matter.
The Federal Prosecutor's Office confirmed it had opened an investigation following a complaint it received from the Zurich cantonal prosecutor. It didn't elaborate on what the probe was connected to.
Swiss weekly Weltwoche revealed on Thursday that the investigation was underway. It also claimed the former SNB president Hansueli Raggenbass, who oversaw the central bank during Hidebrand’s tenure, was also being investigated, but prosecutor’s office spokeswoman Jeannette Balmer denied this was the case.
Hildebrand resigned from the SNB last year after he failed to prove he had not been involved in lucrative currency trades by his wife just weeks before he oversaw the introduction of a cap on the Swiss franc's value in 2011.
Hildebrand, who controlled his own portfolio while at the SNB, was later found not to have broken the central bank's old rules, which were tightened up after the scandal.
He joined the SNB in 2003, rising to chairman in 2010, and won praise for helping to orchestrate the 2008 bailout of UBS, which prompted tougher Swiss banking regulations now being phased in.