Mass. R. Dom. Rel. P. Rule 3
Commencement of Action
A civil action is commenced by (1) mailing to the clerk of the proper court by certified or registered mail a complaint and an entry fee prescribed by law, or (2) filing such complaint and an entry fee with such clerk. Actions brought pursuant to G.L. c. 185 for registration or confirmation shall be commenced by filing a surveyor's plan and complaint on a form furnished by the Land Court.