18. John maRS
$24 billion Self-made Score: @ Source: candy, Pet Food age: 83 reSidence: Jackson, Wy PhilanthroPy score: More than a century ago, their grandfather Frank started selling buttercream candy from his kitchen in Tacoma, Washington. Today Mars is the world’s largest candy maker, and this brother-and-sister duo own an estimated two thirds of the $35 billion (sales) behemoth. Mars makes sweets like M&Ms and Milky Way bars plus staples like Uncle Ben’s Rice and pet food brands Pedigree and Sheba. Both siblings have retired from active roles at the company. Jacqueline’s son Stephen Badger is chairman of the board. Intensely private, they don’t comment on their charitable giving.