Ohio Rev. Code Ann. § 5303.22

The petition for a sale of an estate described in section 5303.21 of the Revised Code shall contain a description of such estate, a clear statement of the interest of the plaintiff therein, and a copy of the will, deed, or other instrument of writing by which the estate is created. All persons in being who are interested in the estate, or who may, by the terms of the will, deed, other instrument creating the entailment or other estate, thereafter become interested therein as heir, reversioner, or otherwise, shall be made parties to the action. If the names or residence of persons who should be made parties are unknown to the plaintiff, that fact shall be verified by affidavit of the plaintiff, whereupon the sale may be ordered.