Me. Stat. tit. 14 § 601
When the plaintiff, petitioner or complainant in any judicial proceeding is not an inhabitant of the State, every original summons, writ, petition or complaint shall, upon motion of an adverse party made within 20 days of service upon him, be indorsed by a sufficient inhabitant of the State, or security for costs furnished by deposit in court in such amount as the court shall direct. If pending such action, the plaintiff, petitioner or complainant removes from the State, such an indorser shall be procured or security for costs furnished on motion, but if one of such plaintiffs, petitioners or complainants is an inhabitant of the State, no indorser or security shall be required except by special order of the court. The name of an attorney of this State upon such summons, writ, petition or complaint will be deemed to have been placed there to meet the requirements of this section in the absence of any words used in connection therewith showing a different purpose.
14 M.R.S. § 601