1976—Subsec. (a). Pub. L. 94–455, § 1906(b)(13)(A), struck out “or his delegate” after “Secretary”.

Subsec. (b). Pub. L. 94–455, § 2004(c)(3), substituted provisions relating to extension of time for payment for a reasonable cause for provisions relating to extension of time for payment for undue hardship to the estate.

Subsec. (c). Pub. L. 94–455, § 1906(b)(13)(A), struck out “or his delegate” after “Secretary”.

1975—Subsec. (c). Pub. L. 93–625 struck out par. (1) cross reference to interest provisions of section 6601 (b) of this title and struck out par. (2) designation of cross reference to security, now incorporated in present subsec. (c) provision.

1964—Subsec. (b). Pub. L. 88–272 substituted “or periods not in excess of 3” for “not in excess of 2”.

1958—Subsecs. (b), (c). Pub. L. 85–866 added subsec. (b) and redesignated former subsec. (b) as (c).

Amendment by section 2004(c)(3) of Pub. L. 94–455 applicable to estates of decedents dying after Dec. 31, 1976, see section 2004(g) of Pub. L. 94–455, set out as an Effective Date note under section 6166 of this title.

Amendment by Pub. L. 93–625 effective on July 1, 1975, and applicable to amounts outstanding on such date or arising thereafter, see section 7(e) of Pub. L. 93–625, set out as an Effective Date note under section 6621 of this title.

Section 240(c) of Pub. L. 88–272, as amended by Pub. L. 99–514, § 2, Oct. 22, 1986, 100 Stat. 2095, provided that:

“(1) The amendment made by subsection (a) [amending this section] shall apply in the case of any reversionary or remainder interest only if the time for payment of the tax under chapter 11 of the Internal Revenue Code of 1986 [formerly I.R.C. 1954] attributable to such interest, including any extensions thereof, has not expired on the date of the enactment of this Act [Feb. 26, 1964].

“(2) The amendment made by subsection (b) [amending section 925 of I.R.C. 1939] shall apply in the case of any reversionary or remainder interest only if the time for payment of the tax under chapter 3 of the Internal Revenue Code of 1939 attributable to such interest, including any extensions thereof, has not expired on the date of the enactment of this Act [Feb. 26, 1964].”

Section 66(b)(3) of Pub. L. 85–866 provided that: “The amendments made by paragraphs (1) and (2) [amending this section and sections 925 and 926 of I.R.C. 1939] shall apply in the case of any reversionary or remainder interest only if the precedent interest or interests in the property did not terminate before the beginning of the 6-month period which ends on the date of the enactment of this Act [Sept. 2, 1958].”