211 CMR, § 121.04
A Filer must notify the Division in writing of its intent to submit a Rate Filing under M.G.L. c. 176K, § 7(g), not less than 30 days before submitting the Rate Filing. A Filer shall provide a copy of the pre-filing notice to the State Rating Bureau, all Statutory Intervenors, and all other Intervenors permitted to appear in the Filer's last Proceeding for that insurance product. The notice must identify all products for which the Filer will submit a proposed Rate Filing and the date on which the Filer expects to submit the Rate Filing to the Division. The notice also must inform all Intervenors permitted to appear in the Filer's last Proceeding, other than the State Rating Bureau and Statutory Intervenors, that they should advise the Filer if they do not want to receive a copy of the Rate Filing. If a Filer fails to provide a pre-filing notice, the Rate Filing shall be deemed to be filed 30 days after it is submitted to the Division.
211 CMR, § 121.04