Mass. Gen. Laws ch. 231, § 112A

Proceedings before the appeals court or the full court of the supreme judicial court upon a report pursuant to the two preceding sections shall be governed by the Massachusetts Rules of Appellate Procedure. The report shall constitute a notice of appeal within the meaning of said rules, and the entry of such report shall constitute the filing of a notice of appeal for purposes of computing time thereunder. The party aggrieved by an interlocutory finding or order shall be treated as the appellant; the plaintiff shall be treated as the appellant whenever the whole case is reported.