Three members of the Walton family could soon join the club as they're worth over $93 billion each. Elon Musk, Jeff Bezos, and Mark Zuckerberg are among the handful of people on the planet with net worths above $100 billion. Members of this elite group have amassed 12-digit fortunes by owning huge amounts of stock in some of the world's most valuable companies. Most are founders and either current or former CEOs, and some like Warren Buffett would be much richer if they didn't give billions to charity.