Saverin, who helped found the company with $15,000 of his money, was once a 40 percent owner. CEO and founder Mark Zuckerberg is said to have used shady tactics to reduce Saverin's stake by creating a new LLC in a different state that then purchased the original company and diluted his shares. Regardless, Saverin is said to be a 2-4 percent owner of the company, which should bring him a windfall of $2-4 billion tomorrow.
To come up with the savings on the tax bill, sources applied a 15 percent long-term capital gains rate to the shares expected price.
Saverin, for his part, has said his decision to move last September had little do with taxes and was completely due to his need to be a world traveler.