Jurisdiction is defined broadly as the limits imposed on the power of a validly constituted court to hear and determine issues between persons seeking to avail themselves of its process by reference to the subject matter of the issues or to the persons between whom the issues are founded or to the kind of relief sought. The question of jurisdiction of a court is a radical and crucial question of competence because if a court has no jurisdiction to hear and determine a case, the proceedings are and remain a nullity ab initio no matter how well conducted and brilliantly decided they might be, because a defect in competence is not intrinsic but extrinsic to the process of adjudication. It is trite law that jurisdiction of a court is determined by the plaintiffs’ claim as endorsed in the writ of summons and statement of claim even where a Federal Government Agency is involved.
— O.O. Adekeye, JSC. Goldmark & Ors. v. Ibafon Co. & Ors. (2012) – SC.421/2001