맨손으로 거부가된 16명 억만장자 - Jan Koum > 부자가 된 녀석들

Koum, 37, came to the U.S. from the Ukraine when he was 16 years old. His family, struggling to make ends meet, lived on food stamps that they picked up a couple blocks away from Koum's future WhatsApp offices in Mountain View, Calif. In 2009, he and cofounder Brian Acton launched the real-time messaging app with an aim to connect people around the world. It essentially replaces text messaging.

Now with 450 million global users, WhatsApp recently agreed to a $19 billion buyout from Facebook. Koum is expected to make the most from the deal. Forbes estimates he has a 45% stake in the company, giving him a net worth of $6.8 billion. He's come a long way on his modest means.