A former employee of Credit Suisse has been found guilty of stealing data from the Swiss banking giant.

The data, which contained details of anonymous account holders, was later sold to German tax authorities. The ensuing investigation into tax evasion prompted a €150 million fine for Credit Suisse.

According to English-language Swiss news site The Local, the former employee began stealing confidential data from his employer "to kill time, out of passion and historical interest".

The data was discovered by an Austrian IT specialist in a briefcase that the employee left in the gym. The IT specialist sold the data to the German tax authorities for €2.5 million, of which the former Credit Suisse employee took a €320,000 cut, according to the Tribune de Genève.

The employee was given a two-year suspended sentence for breaching bank secrecy laws and money laundering and fined 3,500 Swiss francs (£2,500) for stealing confidential data.

The case bears a resemblence to that of Hervé Falciani, a former employee of HSBC’s Swiss subsidiary. According to reports last year, Falciani attempted to sell data on 24,000 client accounts that he had stolen from the bank to German authorities for $3.4 billion.

They did not buy that data but is had since been used by French and Spanish authorities to crack down on tax evasion.