26 CFR § 1.413-2 - Special rules for plans maintained by more than one employer.
(a) Application of section 413(c) -
(1) In general. Section 413(c) describes certain plans (and each trust which is a part of any such plan) hereinafter referred to as “section 413(c) plans.” A plan (and each trust which is a part of such plan) is deemed to be a section 413(c) plan if it is described in subparagraph (2) of this paragraph. Notwithstanding any other provision of the code (not specifically in conflict with the special rules hereinafter mentioned), a section 413(c) plan is subject to the special rules of section 413(c) (1) through (6) and paragraphs (b) through (g) of this section.
(3) Additional rules.
(i) If a plan is a collectively bargained plan described in § 1.413-1(a), the rules of section 413(c) and this section do not apply, and the rules of section 413(b) and § 1.413-1 do apply to the plan.
(ii) The special rules of section 413(b)(1) and § 1.413-1(b) relating to the application of section 410, other than the rules of section 410(a), do not apply to a section 413(c) plan. Thus, for example, the minimum coverage requirements of section 410(b) are generally applied to a section 413(c) plan on an employer-by-employer basis, taking into account the generally applicable rules such as section 401(a)(5) and section 414 (b) and (c).
(iii) The special rules of section 413(b)(2) and § 1.413-1(c) (relating to (A) section 401(a)(4) and prohibited discrimination, and (B) 411(d)(3) and vesting required on termination, partial termination, or discontinuance of contributions) do not apply to a section 413(c) plan. Thus, for example, the determination of whether or not there is a termination, within the meaning of section 411(d)(3), of a section 413(c) plan is made solely by reference to the rules of sections 411(d)(3) and 413(c)(3).
(iv) The qualification of a section 413(c) plan, at any relevant time, under section 401(a), 403(a) or 405(a), as modified by section 413(c) and this section, is determined with respect to all employers maintaining the section 413(c) plan. Consequently, the failure by one employer maintaining the plan (or by the plan itself) to satisfy an applicable qualification requirement will result in the disqualification of the section 413(c) plan for all employers maintaining the plan.
(c) Exclusive benefit. In the case of a plan subject to this section, the exclusive benefit requirements of section 401(a) shall be applied to the plan in the same manner as under section 413(b)(3) and § 1.413-1(d).
(d) Vesting. Section 411 and the regulations thereunder shall be applied as if all employers who maintain the plan constituted a single employer. The application of any rules with respect to breaks in service under section 411 shall be made under regulations prescribed by the Secretary of Labor. Thus, for example, all the hours which an employee worked for each employer maintaining the plan would be aggregated in computing the employee's hours of service under the plan. See also 29 CFR Part 2530 (Department of Labor regulations relating to minimum standards for employee pension benefit plans).