In Personam Law and Legal Definition

In personam in a Latin term meaning "directed toward a particular person". In a lawsuit in which the case is against a specific individual, the court must have in personam jurisdiction over that person in order to try the case. In addition to the mandatory requirement of having subject-matter jurisdiction, a court needs to acquire in personam jurisdiction over the respondent/defendant. Any order issued by a judge when both subject-matter jurisdiction and in personam jurisdiction has not been properly conferred is void, of no legal force or effect.

In personam jurisdiction is obtained when the respondent/ defendant is properly served with a summons and complaint either by certified mail, by personal service, or by publication (only rarely used and only when the address of the respondent/defendant is unknown). The judgment that applies to that person and is called an "in personam judgment."

In personam is distinguished from in rem, which applies to property or "all the world" instead of a specific person. This technical distinction is relevant in determining where to file a lawsuit and how to serve a defendant. In personam means that a judgment can be enforceable against the person wherever he/she is. On the other hand, if the lawsuit is to determine title to property (in rem) then the action must be filed.