LONDON HSBC, Europe's biggest bank, has been hit by the leaking of client account data in the British tax haven of Jersey which is now being looked at by the country's tax authorities.
The authorities confirmed they were looking into details of clients in Jersey after being handed a list of names, addresses and account balances.
"We can confirm we have received the data and we are studying it. We receive information from a very wide range of sources which we use to ensure the tax rules are being respected," HM Revenue & Customs (HMRC) said in a statement.
HSBC said it was investigating the alleged loss of client data, first reported in The Daily Telegraph, "as a matter of urgency."
"We have not been notified of any investigation in relation to this matter by HMRC or any other authority but, should we receive notification, we will cooperate fully with the authorities," the bank said on Friday.
HSBC said it was "fully committed to adoption of the highest global standards including the procedures for the acceptance of clients."
This marks another potential blow for HSBC which has been criticised by U.S. regulators for lax anti-money laundering controls in Mexico and elsewhere, and last year saw thousands of its Swiss clients probed by the British taxman.
The bank's London-listed shares dipped 0.8 percent by 11:50 a.m. British time, firmer than a 1.6 percent drop by the European banking index.
After the financial crisis, the banking industry around the world is under intense scrutiny over its standards and past practices, which have included mis-selling of financial products and interest rate-rigging. And banks have become caught up in cash-strapped governments' efforts to crack down on tax evaders sheltering money in offshore accounts.
"It feels to me like the banking sector is being seen as a money-stuffed piñata for everyone to have a whack at - be it regulators or governments or consumers," said one of HSBC's 10 biggest investors, who asked not to be named.
"I am very bothered, but is this an HSBC-specific issue? No, I do not think it is. I think that general standards of compliance are being challenged everywhere," the investor said.
Chief executive Stuart Gulliver has not come under much pressure from investors since the damning U.S. money-laundering report as he only took the helm at the start of 2011. But he acknowledged this week it would take the industry time to clean up the mess from past mistakes.
"There are a whole series of things that came from probably a decade in the 2000 to 2008-09 period that have surfaced now that the industry needs to sort out, remediate, and make sure do not happen again," Gulliver said after setting aside more money on Monday for a potential U.S. fine.
HSBC said earlier this week that a U.S. probe into anti-money laundering failures could result in a fine well over $1.5 billion and also lead to criminal charges.
Investors said the U.S. anti-money laundering scandal was a far bigger blow for the bank than a tax investigation would be, but they did not expect management to come under big pressure given the problem across the industry to clean up.
"I do not think it's enough to derail the management. Gulliver is regarded materially more highly than his predecessor," a second top 10 investor in the bank said.
The leaked account data identified 4,388 British-based people holding 699 million pounds in current accounts, and included celebrities, bankers, doctors, mining and oil executives and oil workers, according to the Daily Telegraph report. It also included about 4,000 account holders with addresses outside Britain.
HSBC's clients came under scrutiny from HMRC last year when the tax authority contacted up to 6,000 Swiss client account holders after getting their details following an exchange agreement with French authorities.
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