IRS form used by any “foreign government, international organization, foreign central bank of issue, foreign tax-exempt organization, foreign private foundation, or government of a U.S. possession” receiving U.S.-source income to document status and claim exemption from withholding under section 115(2), 501(c), 892, or 895, or claiming a reduced rate of withholding under section 1443(b) of the Internal Revenue Service code.