The British corporate lawyer David Mills helped Mr Berlusconi to set up offshore companies and tax-haven bank accounts for his holding company Fininvest and its many subsidiaries.

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Throughout the 1990s and early 2000s, private-sector Chinese entrepreneurs could set up offshore ownership structures in Hong Kong, the U.S. or the Cayman Islands, that through a new Chinese subsidiary would acquire operating business assets in China.

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Mr Alexander said around 100, 000 employees - mostly teachers, nurses and oil and gas workers - were believed to be paid through offshore payroll services set up in tax havens such as Jersey and could be ineligible for statutory sick pay, but completely unaware of that status.

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It was intended to grow and be handed down from one generation to the next, largely protected from the taxman through the shrewdness of family strategists--and generous grandfather clauses that protect assets accumulating in offshore accounts set up years ago.

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The Lord Ashcroft-owned Bank of Belize was also granted the exclusive right to set up offshore companies in Belize for US and UK citizens.

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