29 C.F.R. § 4068.3 – Notification of and demand for liability.

(a) Notification of liability. Except as provided in paragraph (c) of this section, when the PBGC has determined the amount of the liability under part 4062 and whether or not the liability has already been paid, the PBGC shall notify liable person(s) in writing of the amount of the liability. If the full liability has not yet been paid, the notification will include a request for payment of the full liability and will indicate that, as provided in § 4062.8, the PBGC will prescribe commercially reasonable terms for payment of so much of the liability as it determines exceeds 30 percent of the collective net worth of persons subject to liability in connection with a plan termination. In all cases, the notification will include a statement of the right to appeal the assessment of liability pursuant to part 4003.
(b) Demand for liability. Except as provided in paragraph (c) of this section, if person(s) liable to the PBGC fail to pay the full liability and no appeal is filed or an appeal is filed and the decision on appeal finds liability, the PBGC will issue a demand letter for the liability—
1. (1) If no appeal is filed, upon the expiration of time to file an appeal under part 4003; or
2. (2) If an appeal is filed, upon issuance of a decision on the appeal finding that there is liability under this part.
  The demand letter will indicate that, as provided in § 4062.8, the PBGC will prescribe commercially reasonable terms for payment of so much of the liability as it determines exceeds 30 percent of the collective net worth of such persons.
(c) Special rule. Notwithstanding paragraphs (a) and (b) of this section, the PBGC may, in any case in which it believes that its ability to assert or obtain payment of liability is in jeopardy, issue a demand letter for the liability under this part immediately upon determining the liability, without first issuing a notification of liability pursuant to paragraph (a) of this section. When the PBGC issues a demand letter under this paragraph, there is no right to an appeal pursuant to part 4003 of this chapter.