26 U.S.C. § 892: Income of foreign governments and of international organizations

stocks, bonds, or other domestic securities owned by such foreign governments, or financial instruments held in the execution of governmental financial or monetary policy, or interest on deposits in banks in the United States of moneys belonging to such foreign governments, derived from the conduct of any commercial activity (whether within or outside the United States), received by a controlled commercial entity or received (directly or indirectly) from a controlled commercial entity, or derived from the disposition of any interest in a controlled commercial entity. holds (directly or indirectly) any interest in such entity which (by value or voting interest) is 50 percent or more of the total of such interests in such entity, or holds (directly or indirectly) any other interest in such entity which provides the foreign government with effective control of such entity. For purposes of this title, a foreign government shall be treated as a corporate resident of its country. A foreign government shall be so treated for purposes of any income tax treaty obligation of the United States if such government grants equivalent treatment to the Government of the United States. The income of international organizations received from investments in the United States in stocks, bonds, or other domestic securities owned by such international organizations, or from interest on deposits in banks in the United States of moneys belonging to such international organizations, or from any other source within the United States, shall not be included in gross income and shall be exempt from taxation under this subtitle. The Secretary shall prescribe such regulations as may be necessary or appropriate to carry out the purposes of this section.