Mass. Gen. Laws ch. 241, § 21: Stranger claiming paramount title

Section 21. A person who has not appeared and who claims to hold by title paramount to that under which the petitioner claims as a co-tenant shall not be concluded by the partition, but may maintain his action for the land against any or all of the parties, or persons holding under them, within the time in which he might have brought such action if the petition for partition had not been filed.