26 U.S.C. § 1473: Definitions

any payment of interest (including any original issue discount), dividends, rents, salaries, wages, premiums, annuities, compensations, remunerations, emoluments, and other fixed or determinable annual or periodical gains, profits, and income, if such payment is from sources within the United States, and any gross proceeds from the sale or other disposition of any property of a type which can produce interest or dividends from sources within the United States. Such term shall not include any item of income which is taken into account under section 871(b)(1) or 882(a)(1) for the taxable year. Subparagraph (B) of section 861(a)(1) shall not apply. with respect to any corporation, any specified United States person which owns, directly or indirectly, more than 10 percent of the stock of such corporation (by vote or value), with respect to any partnership, any specified United States person which owns, directly or indirectly, more than 10 percent of the profits interests or capital interests in such partnership, and any specified United States person treated as an owner of any portion of such trust under subpart E of part I of subchapter J of chapter 1, and to the extent provided by the Secretary in regulations or other guidance, any specified United States person which holds, directly or indirectly, more than 10 percent of the beneficial interests of such trust. In the case of any financial institution described in section 1471(d)(5)(C), clauses (i), (ii), and (iii) of subparagraph (A) shall be applied by substituting “0 percent” for “10 percent”. any corporation the stock of which is regularly traded on an established securities market, any corporation which is a member of the same expanded affiliated group (as defined in section 1471(e)(2) without regard to the last sentence thereof) as a corporation the stock of which is regularly traded on an established securities market, any organization exempt from taxation under section 501(a) or an individual retirement plan, the United States or any wholly owned agency or instrumentality thereof, any State, the District of Columbia, any possession of the United States, any political subdivision of any of the foregoing, or any wholly owned agency or instrumentality of any one or more of the foregoing, any bank (as defined in section 581), any real estate investment trust (as defined in section 856), any regulated investment company (as defined in section 851), any common trust fund (as defined in section 584(a)), and is exempt from tax under section 664(c), or is described in section 4947(a)(1). The term “withholding agent” means all persons, in whatever capacity acting, having the control, receipt, custody, disposal, or payment of any withholdable payment. The term “foreign entity” means any entity which is not a United States person.