Agribusiness juggernaut Cargill has produced more billionaires than any other company. The extensive Cargill-MacMillan clan, which still controls the privately held firm, counts 21 three-comma heirs, according to Forbes.

The business was founded in Iowa in 1865 by patriarch W W Cargill as a single grain storage warehouse. Cargill is now America's largest private company, spanning global trading in crops, food ingredients, meat and energy.

The richest family member is Pauline MacMillan Keinath, the company's largest individual shareholder with roughly a 13% stake and a fortune of $9.5 billion (£7.1bn). Pictured is scion Martha MacMillan, who is worth $1.7 billion (£1.3bn).

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