Facebook IPO: A Gold-Mine?

Facebook Inc. (FB)’s $11.8 billion initial public offering (IPO), will cement the status of 27-year-old Mark Zuckerberg as one of the world’s richest men and put his social network among the highest-valued companies in the U.S.

Facebook is offering about 337.4 million shares for $28 to $35 each, according to a regulatory filing yesterday. At the upper end of that range, the co-founder’s stake would be $17.6 billion, making him richer than Microsoft Corp.’s Steve Ballmer and Russian steel billionaire Vladimir Lisin, who are both twice his age, according to the Bloomberg Billionaires Index.

Zuckerberg, who began the service for Harvard classmates as a 19-year-old in his dorm room, built Facebook into the most popular social-networking site in the world, topping 900 million users last quarter.

The Facebook CEO plans to sell 30.2 million shares of his stake in the social network when it publicly offers its stock later this month. If the company’s IPO prices at the top of its $28 to $35 per-share range, Zuckerberg would pocket a “cool” $1.1 billion.

However, most of that cash will go straight to Uncle Sam and California. Zuckerberg plans to partially exercise a major stock options grant, and will use almost all of the cash he raises from his IPO sale to pay off the taxes on that maneuver.

Facebook, while preparing for the IPO, has remained active on other fronts. After being sued by Yahoo! Inc. (YHOO) in March for patent infringement, the company has been looking to buy intellectual property from other owners of it. Facebook plans to spend $550 million on some of the patents Microsoft had earlier said it would purchase from AOL Inc.