Yes, it is possible for out-of-state defendants to be joined in a lawsuit filed in a state where one of the defendants is located. This is known as “joinder” and it allows multiple defendants to be included in a single lawsuit when they have common questions of law or fact.

In the U.S. legal system, a court has jurisdiction over a defendant if the defendant has sufficient minimum contacts with the state, meaning that the defendant has voluntarily availed themselves of the benefits of the state or has caused harm within the state. If a court has jurisdiction over a defendant, the court may also have jurisdiction over other defendants who are related to the lawsuit.

There are different types of joinder, like permissive joinder and compulsory joinder, which are based on the different laws of the state and federal, and the rules of the court. Joinder can be a complex legal process and it’s best to consult with an attorney who is knowledgeable in the laws of the state where the lawsuit is being filed, and the specific facts of your case.