http://finance.yahoo.com/news/facebook-co-founder-saverin-gives-up-u-s–citizenship-before-ipo.html

Facebook plans to raise as much as $11.8 billion through the IPO, the biggest in history for an Internet company. Saverin’s stake is about 4 percent, according to the website Who Owns Facebook. At the high end of the IPO valuation, that would be worth about $3.84 billion. His holdings aren’t listed in Facebook’s regulatory filings.

Saverin, 30, joins a growing number of people giving up U.S. citizenship, a move that can trim their tax liabilities in that country.

Renouncing citizenship is an option chosen by increasing numbers of Americans. A record 1,780 gave up their U.S. passports last year compared with 235 in 2008, according to government records.

Income-tax rates for top U.S. earners will rise to 39.6 percent from 35 percent next year, and rates on capital gains and dividends also are scheduled to rise unless Congress blocks the increases.

I presume Mr Saverin’s tax liabilities will be lower than 35% since his IPO income will be from capital gains.