2014—Subsec. (e)(1). Pub. L. 113–295 struck out “For purposes of the preceding sentence, a taxpayer shall be treated as not having engaged in an activity during any taxable year beginning before January 1, 1970.” at end.

1988—Subsec. (e)(2). Pub. L. 100–647 substituted “activity for 3 (or 2 if applicable)” for “activity for 2”.

1986—Subsec. (d). Pub. L. 99–514 substituted “3” for “2” before “or more” in first sentence and “ ‘2’ for ‘3’ and ‘7’ for ‘5’ ” for “the period of 7 consecutive taxable years for the period of 5 consecutive taxable years” in second sentence.

1982—Subsec. (a). Pub. L. 97–354 substituted “an S corporation” for “an electing small business corporation (as defined in section 1371(b))”.

1976—Subsecs. (d), (e)(3). Pub. L. 94–455, § 1906(b)(13)(A), struck out “or his delegate” after “Secretary”.

Subsec. (e)(4). Pub. L. 94–455, § 214(a), added par. (4).

1971—Subsec. (e). Pub. L. 92–178 added subsec. (e).

Amendment by Pub. L. 113–295 effective Dec. 19, 2014, subject to a savings provision, see section 221(b) of Pub. L. 113–295, set out as a note under section 1 of this title.

Amendment by Pub. L. 100–647 effective, except as otherwise provided, as if included in the provision of the Tax Reform Act of 1986, Pub. L. 99–514, to which such amendment relates, see section 1019(a) of Pub. L. 100–647, set out as a note under section 1 of this title.

Amendment by Pub. L. 99–514 applicable to taxable years beginning after Dec. 31, 1986, see section 151(a) of Pub. L. 99–514, set out as a note under section 1 of this title.

Amendment by Pub. L. 97–354 applicable to taxable years beginning after Dec. 31, 1982, see section 6(a) of Pub. L. 97–354, set out as an Effective Date note under section 1361 of this title.

Pub. L. 94–455, title II, § 214(c), Oct. 4, 1976, 90 Stat. 1549, provided that: “The amendments made by this section [amending this section and section 6212 of this title] shall apply with respect to taxable years beginning after December 31, 1969; except that such amendments shall not apply to any taxable year ending before the date of the enactment of this Act [Oct. 4, 1976] with respect to which the period for assessing a deficiency has expired before such date of enactment.”

Pub. L. 92–178, title III, § 311(b), Dec. 10, 1971, 85 Stat. 526, provided that: “The amendment made by subsection (a) [amending this section] shall apply to taxable years beginning after December 31, 1969.”

Pub. L. 91–172, title II, § 213(d), Dec. 30, 1969, 83 Stat. 572, provided that: “The amendments made by this section [enacting this section, amending section 6504 of this title, and repealing section 270 of this title] shall apply to taxable years beginning after December 31, 1969.”