The Top 10 World's Richest Entrepreneurs
10. Mark Zuckerberg - $ 28.5 billion
Not even 30 years old yet, Facebook founder and CEO Mark Zuckerberg ranks as No. 21 on the Forbes Rich List. Shares of the 10-year-old company are up about 130 percent over last year, which helped the company find much of the $19 billion it used last month to pay for the text-messaging tool, WhatsApp.