(Bloomberg) -- UBS Group is being investigated by the U.S. over whether it helped Americans evade taxes by improperly using securities that let owners conceal their identity, three people familiar with the matter said.

The new investigation, which comes six years after the bank resolved a separate tax-evasion case with the Justice Department, focuses on bearer securities, which can be used like cash, according to one of the people, who like the others, asked not to be identified because the investigation isn’t public.

“UBS has so far handled these investigations pretty cleverly and has always gotten away relatively lightly,” said Dieter Hein, a Kronberg, Germany-based analyst for AlphaValue SAS. “If there is something to these new accusations, I would expect UBS to get away less lightly, as they would be a repeat offender.”

Switzerland has been viewed not only as a safe harbor for global investors, but also as a secret haven for wealthy individuals looking to protect their assets. The U.S. has criminal investigations of a dozen Swiss banks, and another 100 are seeking to avoid prosecution. More than 52,000 Americans have voluntarily disclosed their accounts to the Internal Revenue Service.


A whistle-blower is aiding the investigation, which is being led by the U.S. Attorney’s Office in the Brooklyn borough of New York City, according to the person. That office is headed by Loretta Lynch, who has been nominated to replace Attorney General Eric Holder. Agents with the Federal Bureau of Investigation are also working on the probe, another person said.

Shares in UBS were down 3% at 9:23 a.m. in Zurich trading. That compares with a decline of 1.5% in the 45- member Bloomberg Europe Banks and Financial Services Index.

Marsha Askins, a New York-based spokeswoman for UBS, Peter Carr, a spokesman for the Justice Department, Chris Sinos, an FBI spokesman, and William Muller, executive assistant U.S. attorney in Brooklyn, declined to comment on the UBS investigation.

In 2009, UBS avoided prosecution by paying $780 million, admitting it fostered tax evasion and disclosing to the U.S. the names of 250 American clients. UBS later settled a U.S. lawsuit by revealing the names of 4,450 more account holders. A Credit Suisse Group AG subsidiary pleaded guilty in May to helping Americans cheat on their taxes.

Bearer securities have largely disappeared following a 1982 law that stripped them of tax advantages for issuers and holders.

Prosecutors are also investigating whether Zurich-based UBS tried to cover up the conduct after it become known by bank officials, according to the Wall Street Journal, which earlier reported the investigation.

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