In fact, according to Bloomberg, the 44-year-old is now one of the youngest female billionaires in the world.
Sandberg owns over 12 million shares in the Menlo Park-based company. Wednesday, Facebook closed at a record $58 a share, making her stake in the company around $750 million. That's on top of the $300 million she's collected selling Facebook shares since its IPO in 2012.