RSA 498:5-e Extinguishment of Mineral Rights.

I. A person claiming title to real property may bring an action in superior court to extinguish rights to minerals deeded at least 50 years before the filing of the action, by a predecessor in title, to any person who is unknown to the plaintiff or cannot be located, or if the party who may hold such mineral rights is a corporation no longer in existence or doing business or whose existence has been legally terminated.
II. If the plaintiff describes in the complaint as parties defendant "the unknown persons who claim any interest or estate in (and to) the subject matter of this action," it shall not be necessary to set forth any further description of the unknown persons. If the plaintiff annexes to the complaint an affidavit setting forth the facts and the efforts made to asc