Amended complaint is a revision of the original complaint, previously filed by the plaintiff. When a party to a suit or complaint, makes a modification in the original complaint then the party is said to have amended the complaint. The amendment must be made in writing. Amendments may need to be done for a variety of reasons. For example, a plaintiff may wish to amend his/her complaint to include additional causes of action, or requests for relief, or to name additional parties as defendants to the action.
Rule 15 of the federal rules of civil procedure (USCS Fed Rules Civ Proc R 15) provides that a plaintiff may amend his complaint as a matter of course, if the defendant has not filed an answer to the original complaint. If the defendant has filed his answer to the original complaint, the plaintiff may amend his complaint only by consent of the defendant, or with the court’s permission. Usually most courts freely allow a plaintiff to amend his complaint unless the amendment would substantially prejudice the defendant.
An amended complaint must also be served upon the defendant. The defendant is then allowed an opportunity to respond to it.