Eventually he moved back to India, bringing back with him an intangible commodity: marketing and business practices accrued in the Gulf.

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The test has been expanded to include not only direct benefits, but also intangible benefits such as reputational and business interests, as is evident in the recent highly-publicized case of Rajat Gupta.

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Some are unique to the business, such as the strategic needs of the buyer or the existence of intangible assets such as patents and trademarks.

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As with any business deal where you're being asked to pay hard, cold cash for an intangible service, the buyer should beware.

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Whenever anyone points to the fragility of his business empire, in terms of losses or lack of tangible assets, Mr Branson points to the intangible benefit locked up in his brands.

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