Pub. L. 119–21, title VII, § 70302(e), (f), “(e) “(1) Except as otherwise provided in this subsection or subsection (f)(1), the amendments made by this section [enacting this section and amending sections 41, 56, 59, 144, 174, 195, 263, 263A, 280C, 543, 864, 1016, and 1202 of this title] shall apply to amounts paid or incurred in taxable years beginning after “(2) “(A) The amendment by subsection (b)(1)(C)(ii) [amending section 174 of this title] shall apply to property disposed, retired, or abandoned after “(B) The amendment made by subsection (b)(1)(C)(ii) shall not be construed to create any inference with respect to the proper application of section 174(d) of the Internal Revenue Code of 1986 with respect to taxable years beginning before “(3) The amendment made by subsection (b)(2)(B) [amending section 280C of this title] shall apply to taxable years beginning after “(4) The amendment made by subsection (b)(2)(B) shall not be construed to create any inference with respect to the proper application of section 280C(c) of the Internal Revenue Code of 1986 with respect to taxable years beginning before “(f) “(1) “(A) At the election of an eligible taxpayer, paragraphs (1) and (3) of subsection (e) shall each be applied by substituting ‘“(B) For purposes of this paragraph, the term ‘eligible taxpayer’ means any taxpayer (other than a tax shelter prohibited from using the cash receipts and disbursements method of accounting under section 448(a)(3)) which meets the gross receipts test of section 448(c) for the first taxable year beginning after “(C) In the case of any taxpayer which elects the application of subparagraph (A)—“(i) such election may be treated as a change in method of accounting for purposes of section 481 of such Code for the taxpayer’s first taxable year affected by such election,“(ii) such change shall be treated as initiated by the taxpayer for such taxable year,“(iii) such change shall be treated as made with the consent of the Secretary, and“(iv) subsection (c) shall not apply to such taxpayer.“(D) An election under section 280C(c)(2) of the Internal Revenue Code of 1986 (or revocation of such election) for any taxable year beginning after “(2) “(A) In the case of any domestic research or experimental expenditures (as defined in section 174A, as added by subsection (a)) which are paid or incurred in taxable years beginning after “(i) to deduct any remaining unamortized amount with respect to such expenditures in the first taxable year beginning after “(ii) to deduct such remaining unamortized amount with respect to such expenditures ratably over the 2-taxable year period beginning with the first taxable year beginning after “(B) In the case of a taxpayer who makes an election under this paragraph—“(i) such taxpayer shall be treated as initiating a change in method of accounting for purposes of section 481 of the Internal Revenue Code of 1986 with respect to the expenditures to which the election applies,“(ii) such change shall be treated as made with the consent of the Secretary, and“(iii) such change shall be applied only on a cut-off basis for such expenditures and no adjustments under section 481(a) shall be made.“(C) The Secretary of the Treasury (or the Secretary’s delegate) shall publish such guidance or regulations as may be necessary to carry out the purposes of this paragraph, including regulations or guidance allowing for the deduction allowed under subparagraph (A) in the case of taxpayers with taxable years beginning after
Pub. L. 119–21, title VII, § 70302(c), “(1) The amendments made by subsection (a) [enacting this section] shall be treated as a change in method of accounting for purposes of section 481 of the Internal Revenue Code of 1986 and—“(A) such change shall be treated as initiated by the taxpayer,“(B) such change shall be treated as made with the consent of the Secretary, and“(C) such change shall be applied only on a cut-off basis for any domestic research or experimental expenditures (as defined in section 174A(b) of such Code (as added by this section) and determined by applying the rules of section 174A(d) of such Code) paid or incurred in taxable years beginning after “(2) In the case of a taxable year which begins after “(A) paragraph (1)(C) shall not apply, and“(B) the change in method of accounting under paragraph (1) shall be applied on a modified cut-off basis, taking into account for purposes of section 481(a) of such Code only the domestic research or experimental expenditures (as defined in section 174A(b) of such Code (as added by this section) and determined by applying the rules of section 174A(d) of such Code) paid or incurred in such taxable year but not allowed as a deduction in such taxable year.”