Net investment income
(e) Net investment income attributable to certain entities(1) Distributions from estates and trusts(i) In general. Net investment income includes a beneficiary's share of distributable net income, as described in sections 652(a) and 662(a), to the extent that, under sections 652(b) and 662(b), the character of such income constitutes gross income from items described in paragraphs (a)(1)(i) and (ii) of this section or net gain attributable to items described in paragraph (a)(1)(iii) of this section, with further computations consistent with the principles of this section, as provided in 1.1411-3(e).