Swiss banks operate under the Swiss laws which protect them from disclosing the details of the account holder to any one, unless asked by the highest investigating authority of a country with substantial and concrete evidence that the depositor has infact laundered the money, by ill-gotten means, in that country. Also, such a process is very time consuming and laborious. But such a protection of law doesn't exist in most other countries, including India. So, they can't operate here.
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Swiss banks do not want to operate in india , since they do not want to be regulated by RBI. RBI \'s regulations are very strict about disclosures and their Inspections are very inconvenient to FGN Banks .. naturally swiss banks do not want to take PANGA with RBI