Ohio Rev. Code § 163.07
When the residence of the owners is known and is within this state, notice of the filing of a petition as provided in section 163.05 of the Revised Code shall be given to all such owners by serving a summons and a copy of such petition in the manner of service of summons in civil actions. When the residence of the owners is unknown, and as to all who cannot be served within the state, notice shall be given by publishing the substance of the petition, and a statement of the date of the filing thereof and of the date on and after which the matter may be heard, once a week for two consecutive weeks, in a newspaper of general circulation in the county, or shall be given by registered mail. When service is made by publication, section 2703.16 of the Revised Code shall be complied with.
Unless a person acquiring any interest in any property described in an appropriation petition after the filing thereof moves to be made an additional party defendant prior to the date that the case is set for the jury trial on compensation or to any journalization of a settlement entry, he shall be bound by the final judgment, without right of appeal except as to distribution, and shall receive such compensation as was awarded to his predecessor in interest to the extent that he has succeeded thereto.
R.C. §163.07