The purpose of Subpart F is to deny a tax deferral for ‘movable’ income earned through a foreign corporation. Under Subpart F, certain types of income (such as dividends, interest, rents, and royalties) earned by a foreign corporation are taxable to the CFC’s U.S. shareholders in the year earned even though the corporation does not distribute the income to its shareholders. Subpart F operates by treating the shareholders as if they had actually received the income. The undistributed income of a CFC that is taxable to its U.S. shareholders under the Subpart F rules is referred to as “Subpart F income.”