The second would allow firms to aggregate their tax liability across all countries.

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Second, even if we succeeded on establishing their liability, PwC India had viable arguments that they were at most reckless in conducting their audits, and did not act with actual knowledge of the fraud.

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That's even before taking into account Merck's legal liability for the withdrawn painkiller Vioxx, once its second-best seller after Zocor.

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One such scheme, known as Working Wheels, involved the setting up of a business purportedly selling second-hand cars to help wealthy clients reduce their tax liability.

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Second, the lease lowers the value of the business (because it is a liability), making it easier for successor owners to afford to buy out your interest in the business.

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