A former employee of the leading Swiss bank UBS has been sentenced to 40 months in jail and given a suspended fine for passing secret bank data to the German authorities.
The Federal Criminal Court on Monday found the defendant guilty of industrial espionage, money laundering and illegal possession of ammunition.
However, the judges cleared him of accusations of breaching Swiss banking secrecy laws.
Observers point out that the verdict is based largely on circumstantial evidence and can still be appealed against.
The 45-year former banker, who has denied any wrongdoing, was accused of selling at least 233 sets of bank client data to the German state of North Rhine-Westphalia for about €1.45 million (CHF1.6 million) in 2012.
He was employed by UBS between 2005 and 2012 and apparently bought an apartment on the Spanish island of Mallorca with the money paid by the German authorities but sold it again later.
The verdict was handed down in absentia as the defendant dodged the trial despite two summonses earlier this month. He lives in neighbouring Germany and is unlikely to be extradited to Switzerland.
At least five former bank employees have been convicted by Swiss courts for selling stolen client data to Germany and France since 2011.
The latest case is part of a decade-old dispute between Switzerland and Germany as well as other countries over untaxed assets.
Two years ago, Switzerland implemented regulations on the automatic exchange of fiscal data about residents' international accounts in a bid to avert cross-border tax evasion.
Switzerland, whose banks have paid out billions to other countries to settle charges they helped foreigners hide wealth, has aggressively prosecuted whistleblowers who leak banking data.
swissinfo.ch with SDA-ATS and Reuters; urs