So long, America

Ex-US citizen, Eduardo Saverin Source: Getty

At a time when multinationals are targeted for not paying their "fair share" of tax, attentions have shifted to one individual wanting to cut his tax bill.

Eduardo Saverin, the billionaire co-founder of Facebook, decided to renounce his US citizenship before the company undertook its initial public offering (IPO) last month.

Saverin, who has a 4% stake in the website, is expected to make around $4 billion from the float.

If Saverin had kept his US citizenship he would have been liable to US capital gains tax. Saverin, now a Singapore citizen, will also benefit from any future investments since Singapore does not have a capital gains tax.

Saverin, however, won't escape all US taxes. Americans who give up their citizenship are liable to an exit tax on the capital gains from their stock holdings, even...