A federal appeals court in a precedential ruling has clarified that parties seeking to amend complaints or add new parties to litigation after deadlines are required to show good cause under federal rules as to why their request should be granted.

The U.S. Court of Appeals for the Third Circuit reached its decision in the case of Premier Comp Solutions v. UPMC, rejecting plaintiff Premier Comp Solutions’ appeal of the district court’s ruling that Federal Rule of Civil Procedure 16(b)(4) applied to the plaintiffs’ request to add a party to the litigation after scheduling order deadline had passed.