He then went on to provide information to investigators looking into UBS's private banking business.

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UBS's private-banking business in five years.

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This move by Citigroup is also the first by a major global bank to expand retail banking services in India since 2008 with many competitors like Barclays, UBS and JPMorgan scaling down retail and private banking operations in recent years.

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As with UBS, the investigation of Credit Suisse concerns historical private banking services provided on a cross-border basis to U.S. persons.

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