Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 175, § 180D

The receiver of any company of which this commonwealth is the domiciliary state, appointed under section six, section one hundred and eighty B or section one hundred and eighty C, shall, within twenty days after his appointment, give notice thereof to all policyholders of the company by written notice, in a form prescribed by the court, sent by mail, postage prepaid, to the last address of the insured appearing on the records of the company.