§ 4219.18 Withdrawal in a plan year in which substantially all employers withdraw.

(a) General rule. An employer that withdraws in a plan year in which substantially all employers withdraw from the plan shall be liable to the plan for de minimis amounts if the employer's initial withdrawal liability was reduced pursuant to section 4209(a) or (b) of ERISA.

(b) Amount of liability. An employer's liability for de minimis amounts under this section shall be determined pursuant to § 4219.13.

(c) Plan sponsor's obligations. The plan sponsor of a plan that experiences a withdrawal described in paragraph (a) shall—

(1) Determine and collect initial withdrawal liability of every employer that has completely or partially withdrawn, in accordance with sections 4201 and 4202 of ERISA;

(2) Notify each employer that is or may be liable under this section, in accordance with paragraph (d) of this section;