29 CFR § 4000.21 - What are these rules for determining the filing or issuance date about?
Where the particular regulation calls for their application, the rules in this subpart C of part 4000 tell you how we will determine the date you send us a filing and the date you provide an issuance to someone other than us (such as a participant). These rules do not cover payments to third parties. In addition, they do not cover filings with us that are not made under our regulations, such as procurement filings, litigation filings, and applications for employment with us. In some cases, the PBGC regulations tell you to comply with requirements that are found somewhere other than in the PBGC's own regulations (e.g., requirements under the Internal Revenue Code (Title 26, USC)). In meeting those requirements, you should follow any applicable rules under those requirements for determining the filing and issuance date. (Subpart A tells you what filing methods you may use for filings with us. Subpart B tells you what methods you may use to issue a notice or otherwise provide information to any person other than us. Subpart D tells you how to compute various periods of time. Subpart E tells you how to maintain required records in electronic form.)