D.C. Code § 47-1810.02
Section 7231 of D.C. Law 18-111 provided: "Sec. 7231. Implementation of combined reporting reform. The Council shall pass legislation to require, for tax years beginning after December 31, 2010, that all corporations taxable in the District of Columbia shall determine the income apportionable or allocable to the District of Columbia by reference to the income and apportionment factors of all commonly controlled corporations organized within the United States with which they are engaged in a unitary business."
Section 203(a) of D.C. Law 13-305 provided: "(a) Section 202(a) through (e) shall apply for all tax years beginning after December 31, 2000."
Applicability of D.C. Law 21-36: Section 7132(e)(2) of D.C. Law 21-36 provided that § 7132(d) of the act shall apply to tax years beginning after December 31, 2014.