26 CFR § 51.11
Applicability date
June 25, 2020
(a) Except as otherwise provided in this section, §§51.1 through 51.10 apply on and after July 28, 2014.
(b) Section 51.2(e)(3) applies on and after July 24, 2017.
[T.D. 9684, 79 FR 43645, July 28, 2014, as amended by T.D. 9823, 82 FR 34612, July 26, 2017]