HSBC's discomfort over the theft of client data from its private banking operations in Geneva by an IT insider has deepened as it emerges that the breach may have affected thousands of customers rather than the single-digit figure initially claimed by the bank.
HSBC earlier this week confirmed the theft of the private banking details of some of its wealthiest customers by an IT employee between late 2006 and early 2007. The bank maintained that the breach had affected fewer than ten clients before it was curtailed by a police surveillance operation in 2008.
However, French daily Le Figaro is reporting that the transaction histories of up to 4000 French clients of HSBC in Geneva found their way into the hands of tax authorities in August.
The former HSBC employee is understood to have volunteered the data relating to some €6 billion in client assets to French tax investigators.
Another French newspaper, Le Parisien, claims the employee is currently holed up in Nice under police protection.
The case recalls a similar breach at Liechtenstein's main bank, LGT, in which stolen data formed the basis for a huge investigation into tax evasion by German authorities.