There are only 15 people whose wealth is greater than $100 billion (and some would be richer if they weren't giving it away)

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What do Elon Musk, Bill Gates, and Mark Zuckerberg have in common? They’re part of the $100 billion club. That is, the only 15 people on planet Earth who have 12-figure fortunes.

Together, their combined wealth exceeds $2.2 trillion, per the Bloomberg Billionaires Index. That's more than the market cap of Google-parent Alphabet, at $2 trillion, or Amazon at $1.8 trillion.