The only required pleading in a formal proceeding is the "Notice to the Respondent." The respondent may file a response thereto by serving such response on the secretary of the Commission whose address appears in the notice.

The notice shall be sufficient if it states briefly the grounds upon which the proceedings are based. Amendments of the notice may be made at any time before submission to the Commission. If any amendment substantially changes the charge, reasonable time shall be allowed the respondent to respond thereto, including the right of confrontation and cross-examination of any witness whose testimony forms a basis for such amendment. More than one charge may be stated in the notice.