18-C M.R.S. § 3-204

A person desiring notice of an order or filing pertaining to a decedent's estate in which the person has a financial or property interest may file a demand for notice with the court at any time after the death of the decedent, stating the name of the decedent, the nature of the demandant's interest in the estate and the demandant's address or that of the demandant's attorney. The register shall mail a copy of the demand to the personal representative, if one has been appointed. After filing of a demand, an order or filing to which the demand relates may not be made or accepted without notice as prescribed in section 1-401 to the demandant or the demandant's attorney. The validity of an order that is issued or filing that is accepted without compliance with this requirement is not affected by the error, but the petitioner receiving the order or the person making the filing is liable for any damage caused by the absence of notice. The requirement of notice arising from demand under this provision may be waived in writing by the demandant and ceases upon the termination of the demandant's interest in the estate. [PL 2017, c. 402, Pt. A, §2 (NEW); PL 2019, c. 417, Pt. B, §14 (AFF).]