Facebook founder Mark Zuckerberg face a tax bill of approximatly $1.1 billion for 2012, Investors Place reported.
Zuckerberg, currently valued at $13 billion, was placed in the billionaires list after Facebook went public last year, Investors Place reported.
His Facebook public offering exercised a stock option with price set at 6 cents each, and he purchased 60 million shares on the first day, CNN Money reported.
The IRS will treat Facebook shares including the unsold amounts same as ordinary income at the time the options are exercised as a form of compensation, CNN Money reported.
Combining Zuckerberg's 35% 2012 federal tax rate with 13.3% that of California, the total tax rate is 48.3%, almost half of his income.
According to CNN Money, Zuckerberg sold 30.2 million Facebook shares during Facebook's IPO, taking in $1.135 billion to put toward his tax bill payment.
A Facebook spokeswoman declined to comment on Zuckerberg's taxes, CNN Money reported.