RBC Dain Rauscher, the US securities brokerage arm of Royal Bank of Canada, has launched an investigation after some of its clients received anonymous letters - purporting to be from a former employee - stating that their personal data had been stolen.
Around 100 customers are believed to have received the letter, which says the author copied all the client information for thousands of accounts. The letter also says the author has sold the list of RBC Dain Rauscher's clients, and randomly posted the notice to a few clients as a warning to RBC Dain Rauscher.
In a statement, RBC Dain Rauscher says it has notified all of its clients about the matter and has set up a 24 hour-a-day hotline to help clients affected by the situation.
The company says it has begun an investigation in partnership with local and federal police and has hired an outside firm specialising in identity theft.
John Taft, CEO, RBC Dain Rauscher, says so far there is no evidence of fraudulent activity, but the company intends to "identify and prosecute those responsible for this theft of information".
The possible data theft is the latest in a number of high profile security breaches in the US. Earlier this year US banks Wachovia, Bank of America, PNC Bank, and Commerce Bank notified thousands of customers that their accounts may have been breached during a four-year period in which corrupt bank staff sold screen shots of financial records.
A study released by California-based Impulse Research in July this year showed that one in five individuals have fallen victim to identity theft, and the majority of US consumers want to see criminal charges levied against companies that fail to protect their personal data.