Under R.C. 3127.15, Ohio has jurisdiction to make an initial child custody determination if it is the child's home state. The term "home state" is defined as the state where the child has lived with a parent or a person acting as a parent for at least six consecutive months immediately before the commencement of the child custody proceeding.

However, there are exceptions to the home state rule. R.C. 3127.22 provides that Ohio may exercise jurisdiction if it is in the best interest of the child and no other state has jurisdiction or has declined jurisdiction. In Mireles v. Veronie, the court determined that Ohio had jurisdiction over the child custody matter because it was in the child's best interest and no other state had jurisdiction. Mireles v. Veronie, 2020-Ohio-3078, 154 N.E.3d 727 (Ohio Ct. App. 9th Dist. Medina County 2020).

Additionally, R.C. 3127.18 allows Ohio to exercise temporary emergency jurisdiction if the child is present in Ohio and has been abandoned or it is necessary to protect the child because the child, a sibling, or a parent is subjected to or threatened with mistreatment or abuse. In the case of In re H.P., the court found that Ohio had temporary emergency jurisdiction due to the child's presence in Ohio and the need to protect the child from mistreatment. In re H.P., 2015-Ohio-1309, 2015 WL 1511008 (Ohio Ct. App. 8th Dist. Cuyahoga County 2015).

When filing for child custody in Ohio several statutes come into play that outline the obligations and procedures that must be followed to initiate a child custody case.

R.C. 3127.23 requires each party in a child custody proceeding to provide information under oath in their first pleading or an attached affidavit. This information includes the child's present address or whereabouts, places the child has lived within the last five years, and the names and present addresses of individuals with whom the child has lived during that period. The purpose of this requirement is to prevent contradictory rulings from different courts or jurisdictions on the issue of custody.

Additionally, R.C. 2151.27, R.C. 2151.031, R.C. 2151.03, and R.C. 2151.04 define terms and provide guidance on matters related to child custody, abuse, neglect, dependency, and termination of parental rights.