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Facebook CEO Mark Zuckerberg now third richest man in tech

Facebook co-founder and CEO Mark Zuckerberg has an estimated net worth of $18 billion, only behind Bill Gates and Larry Ellison.

Earlier this week, Investment fund GSV Capital bought 225,000 shares in Facebook at an average price of $29.28 each, giving the social network a valuation of about $70 billion. If we take this new number into account, we can extrapolate that Facebook co-founder and CEO Mark Zuckerberg's net worth has passed $18 billion, according to Forbes.

As a result, Zuckerberg is now the third richest man in the technology sector (again, this is assuming that Facebook is really worth $70 billion). Microsoft chairman Bill Gates is still first, followed by Oracle co-founder and CEO Larry Ellison. Zuckerberg passed Apple's Steve Jobs last fall. If we take into account Google's recently falling shares, he has now passed Google co-founders Sergey Brin and Larry Page. Last but not least, he is also richer than Microsoft CEO Steve Ballmer.

Zuckerberg had an estimated worth of $4 billion in 2010. Earlier this year, his wealth increased to $13.5 billion, when Facebook announced that it had raised $1.5 billion at a valuation of approximately $50 billion. Now he's at $18 billion.

The $70 billion valuation is approximately a 40 percent premium to the $50 billion previously used to measure the fortunes of the six Facebook billionaires. The other Facebook billionaires (Dustin Moskovitz, Eduardo Saverin, Sean Parker, Peter Thiel, and Yuri Milner) have thus also become richer.

Again, this is all based on the $70 billion valuation. If we look at secondary markets, Zuckerberg's and his colleague's fortunes could be even higher. Two months ago, a private-market transaction of 100,000 shares of Facebook Class B Common Stock priced at $32.00 apiece gave the website a valuation of $80 billion.

Facebook is going public next year, possibly as soon as Q1 2012. Last month, we heard that Facebook's business was growing faster than previously forecasted and the company's profits were increasing quickly enough to make a valuation of $100 billion justifiable.