§ 4971.
(a)
Initial tax
If at any time during any taxable year an employer maintains a plan to which section 412 applies, there is hereby imposed for the taxable year a tax equal to—
(1)
in the case of a single-employer plan, 10 percent of the aggregate unpaid minimum required contributions for all plan years remaining unpaid as of the end of any plan year ending with or within the taxable year,
(2)
in the case of a multiemployer plan, 5 percent of the accumulated funding deficiency determined under section 431 as of the end of any plan year ending with or within the taxable year, and
(3)
in the case of a CSEC plan, 10 percent of the CSEC accumulated funding deficiency as of the end of the plan year ending with or within the taxable year.
(b)
Additional tax
If—
(1)
a tax is imposed under subsection (a)(1) on any unpaid minimum required contribution and such amount remains unpaid as of the close of the taxable period,
(2)
a tax is imposed under subsection (a)(2) on any accumulated funding deficiency and the accumulated funding deficiency is not corrected within the taxable period, or
(3)
a tax is imposed under subsection (a)(3) on any CSEC accumulated funding deficiency and the CSEC accumulated funding deficiency is not corrected within the taxable period,
there is hereby imposed a tax equal to 100 percent of the unpaid minimum required contribution, accumulated funding deficiency, or CSEC accumulated funding deficiency, whichever is applicable, to the extent not so paid or corrected.
(c)
Definitions
For purposes of this section—
(1)
Accumulated funding deficiency
(3)
Taxable period
The term “taxable period” means, with respect to an accumulated funding deficiency, CSEC accumulated funding deficiency, or unpaid minimum required contribution, whichever is applicable, the period beginning with the end of the plan year in which there is an accumulated funding deficiency, CSEC accumulated funding deficiency, or unpaid minimum required contribution, whichever is applicable, and ending on the earlier of—
(A)
the date of mailing of a notice of deficiency with respect to the tax imposed by subsection (a), or
(B)
the date on which the tax imposed by subsection (a) is assessed.
(4)
Unpaid minimum required contribution
(5)
CSEC accumulated funding deficiency
(d)
Notification of the Secretary of Labor
Before issuing a notice of deficiency with respect to the tax imposed by subsection (a) or (b), the Secretary shall notify the Secretary of Labor and provide him a reasonable opportunity (but not more than 60 days)—
(1)
to require the employer responsible for contributing to or under the plan to eliminate the accumulated funding deficiency, CSEC accumulated funding deficiency, or unpaid minimum required contribution, whichever is applicable, or
(2)
to comment on the imposition of such tax.
(Added [Pub. L. 93–406, title II, § 1013(b)], Sept. 2, 1974, [88 Stat. 920]; amended [Pub. L. 94–455, title XIX, § 1906(b)(13)(A)], Oct. 4, 1976, [90 Stat. 1834]; [Pub. L. 96–364, title II, § 204], Sept. 26, 1980, [94 Stat. 1287]; [Pub. L. 96–596, § 2(a)(1)(J)], (2)(H), Dec. 24, 1980, [94 Stat. 3469], 3471; [Pub. L. 100–203, title IX], §§ 9304(c)(1), 9305(a), Dec. 22, 1987, [101 Stat. 1330–348], 1330–351; [Pub. L. 103–465, title VII, § 751(a)(9)(B)], Dec. 8, 1994, [108 Stat. 5020]; [Pub. L. 104–188, title I, § 1464(a)], Aug. 20, 1996, [110 Stat. 1824]; [Pub. L. 109–280, title I, § 114(e)(1)]–(4), title II, § 212(b), Aug. 17, 2006, [120 Stat. 854], 855, 915; [Pub. L. 110–458, title I], §§ 101(d)(2)(F), 102(b)(2)(I), (3)(A), Dec. 23, 2008, [122 Stat. 5099], 5103; [Pub. L. 113–97, title II, § 202(c)(8)], (9), Apr. 7, 2014, [128 Stat. 1137], 1138; [Pub. L. 115–141, div. U, title IV, § 401(a)(225)]–(228), (b)(44), Mar. 23, 2018, [132 Stat. 1195], 1204.)