Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 79, § 32

If property which is taken in whole or in part by eminent domain or receives injury, for which damages are recoverable under this chapter, is mortgaged, both the mortgagor and the mortgagee, in addition to their rights under the mortgage, shall have the same powers, rights and privileges, and be subject to the same liabilities and duties, as are provided in this chapter for owners of property so taken or injured, and all petitions for the award or assessment of such damages shall state all mortgages which are known by the petitioner to exist upon the property. Mortgagors and mortgagees may join in any such petition, or become parties to any proceedings for the award or assessment of damages under this chapter, and, if the petition is filed by a mortgagor or mortgagee of property taken or injured, the tribunal to which it is presented shall order the petitioner to give notice thereof to all other mortgagors or mortgagees of the same property by serving on each of them, fourteen days at least before the time of hearing, an attested copy thereof and of the order thereon, that they may become parties to the proceedings.