Tax Havens Can Benefit Corporations Taxation as an Art

Tax Loopholes from Investing Internationally

Tax agencies like the IRS aren't ignorant of offshore strategies. They've clamped down on some traditional ways of tax avoidance. There are still loopholes, but most are shrinking more and more every year. In 2004, the IRS amended the Internal Revenue Code (IRC) and began to collect taxes from both American corporations that operate out of another country and American citizens and residents who earn money through offshore investments.
Source: http://www.investopedia.com/articles/basics/03/050803.asp