Ohio Rev. Code Ann. § 3127.21 – Jurisdiction declined - forum non conveniens

(A) A court of this state that has jurisdiction under this chapter to make a child custody determination may decline to exercise its jurisdiction at any time if it determines that it is an inconvenient forum under the circumstances and that a court of another state is a more convenient forum. The issue of inconvenient forum may be raised upon motion of a party, the court's own motion, or at the request of another court.
(B) Before determining whether it is an inconvenient forum, a court of this state shall consider whether it is appropriate for a court of another state to exercise jurisdiction. For this purpose, the court shall allow the parties to submit information and shall consider all relevant factors, including the following:
1. (1) Whether domestic violence has occurred and is likely to continue in the future and which state could best protect the parties and the child;
2. (2) The length of time the child has resided outside this state;
3. (3) The distance between the court in this state and the court in the state that would assume jurisdiction;
4. (4) The relative financial circumstances of the parties;
5. (5) Any agreement of the parties as to which state should assume jurisdiction;
6. (6) The nature and location of the evidence required to resolve the pending litigation, including the testimony of the child;
7. (7) The ability of the court of each state to decide the issue expeditiously and the procedures necessary to present the evidence;
8. (8) The familiarity of the court of each state with the facts and issues in the pending litigation.
(C) If a court of this state determines that it is an inconvenient forum and that a court of another state is a more appropriate forum, it shall stay the proceedings upon condition that a child custody proceeding be promptly commenced in another designated state and may impose any other condition the court considers just and proper.
(D) A court of this state may decline to exercise its jurisdiction under this chapter if a child custody determination is incidental to an action for divorce or another proceeding while still retaining jurisdiction over the divorce or other proceeding.