39 Miss. Code. R. 1-6-101
Each utility subject to the jurisdiction of the Commission shall be assigned an identification number upon receipt of a Certificate of Public Convenience and Necessity. This identification number, after certification, must be provided on the first page of all petitions, pleadings, correspondence and other documents filed with the Commission.
The Executive Secretary may reject any filing made by a utility which does not list the identification number of a public utility upon notice of rejection to the filing utility. The Executive Secretary, upon accepting a filing which conforms to these rules, enters a stamped filed date on the first page of each document which designates the official filing date of the document. The Executive Secretary shall assign a docket number at that time. However, the electronic filing of a case with the Executive Secretary will not result in the publication and noticing of a proceeding until the requisite number of paper copies are received by the Executive Secretary.
39 Miss. Code. R. 1-6-101