More than 10,000 private messages sent between users of Bloomberg’s financial terminals have leaked online, undermining the company’s attempts to restore faith in its ability to keep client data confidential as it scrambles to allay clients’ privacy concerns.

Two lists showing confidential Bloomberg messages between traders at dozens of the world's largest banks and their clients have been online for several years.

The documents, from one particular day in 2009 and also from 2010, contain messages sent in by clients so Bloomberg could extract price data on bonds, credit default swaps and other financial products from traders’ messages.

The messages had been found, a financial markets professional said, through a simple Google search. They were taken down from the internet yesterday.

The apparently accidental leak threatens to unnerve Bloomberg’s clients, coming 72 hours after the unrelated revelation that Goldman Sachs had complained that the news organisation’s journalists had been able to track when users accessed their terminals and which functions they used. – (Copyright The Financial Times Limited 2013 )