Consolidation of lawsuits may be ordered by a court when two or more lawsuits involving the same or similar parties (plaintiff and defendant), legal issues, and factual issues are pending in the same court or in different courts in the same jurisdiction (state court system or federal court system). If the lawsuits are pending in different courts one case may be transferred to the other court, and the cases consolidated there.

Laws and rules regarding the consolidation—or transfer and consolidation—of lawsuits vary from state to state and in the federal court system.

In Oklahoma, the consolidation of lawsuits is governed by the Oklahoma statutes and the rules of the court where the lawsuits are filed. According to Oklahoma law, consolidation may be appropriate when two or more lawsuits share common parties, questions of law, or factual issues, and are pending in the same court or in different courts within the state. The purpose of consolidation is to avoid unnecessary costs or delay, to avoid inconsistent judgments, and to make the court process more efficient. The decision to consolidate is at the discretion of the court, which will consider whether consolidation would serve the interests of justice and judicial economy. If the cases are in different courts, one case may be transferred to the other court for consolidation. In federal courts, similar principles apply under the Federal Rules of Civil Procedure, which allow for consolidation when actions involve a common question of law or fact. The decision to consolidate federal cases is also at the discretion of the federal judge. It's important to note that the specific procedures and requirements for consolidation may vary depending on the particular court's rules and the circumstances of the cases.