Mass. Gen. Laws ch. 185 § 116
All notices required by or given under this chapter by the recorder or any assistant recorder, after original registration, shall be mailed to the person to be notified at the residence and post office address stated in the certificate of title, or in any registered instrument under which he claims an interest, in the office of the recorder or assistant recorder, relating to the parcel of land in question.
All notices and citations directed by special order of the court under this chapter, after original registration, may be served in the manner above stated, and the certificate of the recorder shall be conclusive proof of such service; but the court may in any case order different or further service, by publication or otherwise.
Mass. Gen. Laws ch. 185, § 116