Minn. Stat. § 558A.07: COMPLAINT.

The complaint shall particularly set forth the interests of all persons in the property, whether by way of ownership or lien, so far as known to the plaintiff; and if any such person, or the person's share or interest, is unknown to the plaintiff, or is uncertain or contingent, or the ownership of the inheritance depends upon an executory devise, or there is a contingent remainder, so that such person cannot be named, that fact shall be set forth.