Photo: Michael Buholzer/AFP
UBS will be charged with illegal banking practices and dissimulating tax fraud, the sources said, adding UBS's French subsidiary will also go on trial for complicity.
Five UBS top managers are also facing trial, including Raoul Weil, the former third-in-command at UBS.
The French subsidiary's former number two, Patrick de Fayet, has entered a plea bargain procedure, they said.
France opened a probe into UBS after former employees blew the whistle over the bank's alleged system of setting up dual bookkeeping to hide the movement of capital into Switzerland between 2004 and 2012.
The bank's staff allegedly approached French clients, from wealthy businessmen to sports stars, during receptions, golf tournaments or concerts to convince them to hide their money in Switzerland.
In total, at least 9.76 billion euros ($10.5 billion) were kept from the French tax man, according to the national financial crimes unit.
“My honour will finally be cleared,” said former UBS internal auditing chief Nicolas Forissier, one of the whistleblowers. “The company is going to have to face the truth.”
Forissier was summarily sacked by UBS in 2009 for “gross misconduct”.
In June last year, French prosecutors recommended that UBS face trial for “aggravated laundering of tax fraud proceeds” while its French branch be judged for complicity in these crimes.
The move followed failed negotiations over a plea bargain.
“Those negotiations failed in particular because prosecutors and the bank could not agree on the sum that the bank would have to pay,” said one source close to the case.
UBS has always denied any wrongdoing, saying there was no proof for its implication in any such alleged scheme.
On Monday, it said it rejected both “the allegations and the nature of the charges brought”, a UBS spokesman told AFP in Paris.
The trial will offer the bank “the possibility of responding to the accusations brought against it”, the spokesman said, adding UBS was hoping for a “fair trial”.
A lawyer for the bank, Denis Chemla, said the charges contained “no special surprises” and called them “unfounded”.
Five billion at stake
According to documents that German authorities handed over to French investigators, deposits from some 38,000 French clients with UBS amounted to a total of around 13 billion Swiss francs (12 billion euros, $13 billion), a source close to the case told AFP. Not all these clients are suspected of tax fraud, the source said.
The total fine slapped on UBS could amount to up to half the sums laundered, according to French law. If investigators are right in their estimates, that would mean a fine of up to nearly five billion euros.
French judges already slapped a 1.1 billion euro bond on UBS in 2014, a measure the bank failed to overturn before the European Court of Human rights in January of this year.
The court, which normally hears complaints from individuals, ruled that the bond was “an interim measure which did not prejudge the outcome of the proceedings”.
On the Zurich stock exchange on Monday, UBS shares closed 0.9 percent lower at 15.89 francs, having bounced off the day's low of 15.77.
Headquartered in Zurich, UBS provides financial advice and banking solutions to wealthy, institutional and corporate clients worldwide, as well as private clients in Switzerland.
It calls itself “the world's largest and fastest-growing wealth manager”.