Swiss bank, UBS Group AG, its French unit and six executives have been charged for alleged aggravated tax fraud and money laundering.
Their charge on Monday is the first day of a trial into allegations they helped wealthy clients avoid taxes in France.
After seven years of investigation and aborted settlement negotiations, UBS will also answer allegations that it illegally solicited clients in France.
It risks being fined up to five billion euros (5.76 billion dollars) plus potential damages to the French taxman for the missing revenue.
On the first day of the court hearing on Monday, the defendants’ lawyers raised technicalities to try to get the court to drop the money laundering charges.
They prayed for limiting the proceedings to tax fraud, which carries lighter penalties.
UBS’s lawyer Jean Veil said the French state was asking for 1.6 billion euros in damages, which he told the court was excessive.
“They are asking crazy amounts,” he told the court.
UBS, Switzerland’s largest bank, has said it intends to firmly defend its position.
“After more than six years of legal proceedings, we will finally have the opportunity to respond to the often unfounded allegations that were frequently leaked to the media.
In clear violation of the presumption of innocence and the legal confidentiality of the process,” UBS said in a statement ahead of the trial.
The bank said it would reserve its arguments for the court.
Banks have become more rigorous after the 2008 financial crisis and the banking scandals that followed, while tighter regulations have forced the industry to become more cautious, analysts say.
UBS’s trial in France follows a similar judicial process in the United States, where the bank in 2009 accepted to pay 780 million dollars in a settlement.
In Germany, UBS agreed to a 300 million euro fine in 2014.
During the French investigation, UBS turned down a settlement offer of 1.1 billion euros made by the authorities.
The amount corresponded to what the Swiss bank had already paid as a court bond, according to judicial sources.
The investigation into UBS in the United States began after employee Bradley Birkenfeld revealed a scheme to funnel wealthy customers’ cash from the United States to Switzerland, bypassing U.S. taxman.
Birkenfeld spoke separately to French investigators. Even though he is not due to testify in court in Paris he intends to attend all the hearings.
The whistleblower told mefia that he hoped for a heavy penalty for the Swiss bank. “If they set an example with UBS, most other banks will be scared,” he said.
For money laundering, French criminal law lets judges enforce fines as high as half the amount laundered.
In the French case, prosecutors estimate that up to 10.6 billion euros was denied to the French tax authorities.
The court hearing is due to resume on Thursday and the case is scheduled to continue until Nov. 15.