Massachusetts General Laws Part II. Real and Personal Property and Domestic Relations (Ch. 183-210) Ch. 185, § 65

If a deed in fee is for a part only of the land described in a certificate of title, the assistant recorder shall also, in accordance with the rules and instructions of the court, enter a new certificate for the part of the land not included in the deed. In every case of transfer, the new certificate or certificates shall include all the land described in the old certificate; but no new certificate to a grantee of a part only of the land shall be invalid by reason of the failure of the assistant recorder to enter a new certificate to the grantor for the remaining unconveyed portion. If the land described in a certificate of title is divided into lots, designated by numbers or letters, with measurements of all the bonds, and a plan of said land has been filed with the recorder and verified pursuant to section fifty-one, and a certified copy thereof is recorded in the registration book with the original certificate when the registered owner makes a deed of transfer in fee of one or more of such lots, the assistant recorder may, instead of canceling such certificate and entering a new certificate to the grantor for the part of the land not included in the deed of transfer, enter on the original certificate a memorandum of such deed of transfer, with a reference to the lot or lots thereby conveyed, as designated on said plan, and stating that the certificate is canceled as to such lot or lots. Every certificate with such memorandum shall be as effectual for the purpose of showing the grantor's title to the remainder of the land not conveyed as if the old certificate had been canceled and a new certificate of such land entered; and such process may be repeated so long as there is convenient space upon the original certificate for making such memorandum of sale of lots.