Pub. L. 116-94, div. Q, tit. I, subtit. B, sec. 114
CLASSIFICATION OF CERTAIN RACE HORSES AS 3-YEAR PROPERTY.
SEC. 114. CLASSIFICATION OF CERTAIN RACE HORSES AS 3-YEAR PROPERTY.(a) In General.—Section 168(e)(3)(A)(i) is amended—(1) by striking “January 1, 2018” in subclause (I) and inserting “January 1, 2021”, and(2) by striking “December 31, 2017” in subclause (II) and inserting “December 31, 2020”.(b) Effective Date.—The amendments made by this section shall apply to property placed in service after December 31, 2017.