In general. Section 4943 and §§ 53.4943-1 through 53.4943-11 shall take effect for taxable years beginning after December 31, 1969, except as otherwise provided by such sections.

Special transitional rule. In the case of any acquisition of excess holdings prior to February 2, 1973, section 4943(a)(1) shall not apply if correction occurs (within the meaning of paragraph (c) of § 53.4943-9) within a period ending 90 days after July 5, 1977 extended (prior to the expiration of the original period) by any period which the Commissioner determines is reasonable and necessary (within the meaning of paragraph (b) of § 53.4943-9) to bring about such correction.

Special transitional rule for acquisition by will, etc. (1) The rule in § 53.4943-6(b)(1) whereby holdings not held by a decedent are not treated as acquired under a will shall not apply to acquisitions of after-acquired property of a decedent's estate occurring on or before May 22, 1984.

The rule in § 53.4943-6(b)(1) treating a purchase by an estate as a purchase by a disqualified person where the executor is a disqualified person shall not apply to purchases occurring on or before May 22, 1984.

Special transitional rule for affiliated groups. If on or before May 22, 1984 a foundation holds an interest in a common parent corporation in an affiliated group, as defined in § 53.4943-10(c)(3)(ii), the foundation may elect to have both § 53.4943-8(c)(4) and § 53.4943-10(c)(3) not apply to such common parent corporation. No election may be made to have only one section not apply. Such election shall be made by the governing body of the private foundation at any time prior to February 22, 1985.

Special transitional rule for changes to a business enterprise. Any interest that is not an interest in a business enterprise which becomes an interest in a business enterprise under § 53.4943-10(d)(2) prior to May 22, 1984 will be treated as having been acquired other than by purchase for purposes of section 4943(c)(6).

Special transitional rule for private foundations that qualified as Type III supporting organizations before August 17, 2006. The present holdings of a private foundation that qualified as a Type III supporting organization under section 509(a)(3) immediately before August 17, 2006, and that was reclassified as a private foundation under section 509(a) on or after August 17, 2006, solely as a result of the rules enacted by section 1241 of the Pension Protection Act of 2006, Public Law 109-280 (120 Stat. 780), will be determined using the same rules that apply to Type III supporting organizations under section 4943(f)(7).

Special transitional rule for Type III supporting organizations created as trusts before November 20, 1970. A trust that qualifies as a Type III supporting organization under section 509(a)(3) and meets the requirements of § 1.509(a)-4(i)(9) of this chapter will be treated as a “functionally integrated Type III supporting organization” for purposes of section 4943(f)(3)(A).