26 U.S.C. § 1381: Organizations to which part applies

any organization exempt from tax under section 521 (relating to exemption of farmers’ cooperatives from tax), and which is exempt from tax under this chapter, part II of subchapter H (relating to mutual savings banks, etc.), or subchapter L (relating to insurance companies), or which is engaged in furnishing electric energy, or providing telephone service, to persons in rural areas. An organization described in subsection (a)(1) shall be subject to the tax imposed by section 11. For treatment of income from load loss transactions of organizations described in subsection (a)(2)(C), see section 501(c)(12)(H). Except as provided in paragraph (3), the amendments made by subsections (a) and (b) [enacting this subchapter, amending sections 521 and 6072 of this title, and repealing section 522 of this title ] shall apply to taxable years of organizations described in section 1381(a) of the Internal Revenue Code of 1986 [formerly I.R.C. 1954] (as added by subsection (a)) beginning after December 31, 1962 . Except as provided in paragraph (3), section 1385 of the Internal Revenue Code of 1986 (as added by subsection (a)) shall apply with respect to any amount received from any organization described in section 1381(a) of such Code, to the extent that such amount is paid by such organization in a taxable year of such organization beginning after December 31, 1962 . before the first day of the first taxable year of such organization beginning after December 31, 1962 , or on or after such first day with respect to patronage occurring before such first day,