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Sir Michael Smurfit and family

Smurfit, 70, left Smurfit Kappa last month after 53 years. It refloated, at £2.3 billion, putting Smurfit’s 4.9% stake at £113m. But it is outside his day job that the Monaco-based tycoon claims to have made most money, buying into other firms. His wealth includes one of the world’s largest yachts, plus at least £250m of other assets.