Few people have benefited from Facebook's incredible success more than WhatsApp cofounder Jan Koum.
With an estimated fortune of roughly $9.5 billion, 41-year-old Koum has come a long way from growing up without running water in Soviet-Era Ukraine to creating a messaging app used by 1.2 billion people.
Facebook purchased WhatsApp in 2014 for a jaw-dropping $19 billion, adding Koum to the company board and sending his net worth into the stratosphere.
Koum now leads a team of around 100 people working on WhatsApp, which is used heavily in developing countries like India and Brazil. And he sold over half of his shares in Facebook last year, totaling roughly $5 billion.
Here's how Koum got to where he is today:
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Koum has an estimated net worth of roughly $9.5 billion. His fortune is made up almost entirely from Facebook stock, which he's been selling aggressively over the past year.
But Koum wasn't always wealthy. He was born in Ukraine in 1976 into a household without running water.
Source: Forbes
Here's how he described life in his hometown outside Kiev: "It was so run-down that our school didn't even have an inside bathroom. Imagine the Ukrainian winter, -20°C, where little kids have to stroll across the parking lot to use the bathroom. Society was extremely closed off: you can read 1984, but living there was experiencing it."
Source: Wired
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