52 Pa. Code § 1003.41 – Form and content of informal complaints.

(a) Informal complaints averring a violation of the act, this part or an order of the Authority may be by letter or other writing. A form of informal complaint is not required, but in substance the report, letter or other writing must contain the essential elements of a formal complaint as specified in § 1005.12 (relating to content of formal complaints).
(b) Informal complaints shall be filed with the Clerk.
(c) Subsection (a) supersedes 1 Pa. Code § 35.5 (relating to form and content of informal complaints).

This section cited in 52 Pa. Code § 1001.10 (relating to definitions).