But it's the tax benefit of overseas operations that is the biggest reason why multinationals end up with lower tax rates than the rest of us. It only makes sense that multinationals "put costs in high-tax countries and profits in low-tax countries," says Scott Hodge, president of the Tax Foundation. Those low-tax countries are almost anywhere but the U.S. "When you add in state taxes, the U.S. has the highest tax burden among industrialized countries," says Hodge. In contrast, China's rate is just 25%; Ireland's is 12.5%.
Corporations are getting smarter, not just about doing more business in low-tax countries, but in moving their more valuable assets there as well. That means setting up overseas subsidiaries, then transferring to them ownership of long-lived, often intangible but highly profitable assets, like patents and software.