Multinational firms can artificially shift profits from high-tax to low-tax jurisdictions using a
variety of techniques, such as shifting debt to high-tax jurisdictions. Because tax on the income of
foreign subsidiaries (except for certain passive income) is deferred until income is repatriated
(paid to the U.S. parent as a dividend), this income can avoid current U.S. taxes, perhaps
indefinitely. The taxation of passive income (called Subpart F income) has been reduced, perhaps
significantly, through the use of hybrid entities that are treated differently in different
jurisdictions. The use of hybrid entities was greatly expanded by a new regulation (termed checkthe-box)
introduced in the late 1990s that had unintended consequences for foreign firms. In
addition, earnings from income that is taxed often can be shielded by foreign tax credits on other
income. On average, very little tax is paid on the foreign source income of U.S. firms. Ample
evidence of a significant amount of profit shifting exists, but the revenue cost estimates vary
substantially. Evidence also indicates a significant increase in corporate profit shifting over the
past several years. Recent estimates suggest losses that may approach, or even exceed, $100
billion per year.