1986—Subsec. (a). Pub. L. 99–514 amended subsec. (a) generally, designating existing provisions as par. (1) and adding par. (2).

Amendment by Pub. L. 99–514 effective, except as otherwise provided, as if included in the provisions of the Tax Reform Act of 1984, Pub. L. 98–369, div. A, to which such amendment relates, see section 1881 of Pub. L. 99–514, set out as a note under section 48 of this title.

Section applicable to taxable years ending after July 18, 1984, and to obligations acquired after that date, see section 44 of Pub. L. 98–369, set out as a note under section 1271 of this title.

For provisions directing that if any amendments made by subtitle A or subtitle C of title XI [§§ 1101–1147 and 1171–1177] or title XVIII [§§ 1800–1899A] of Pub. L. 99–514 require an amendment to any plan, such plan amendment shall not be required to be made before the first plan year beginning on or after Jan. 1, 1989, see section 1140 of Pub. L. 99–514, as amended, set out as a note under section 401 of this title.