SCOTUS Decides FRCP 15(c) Relation Back Case: Krupski v. Costa Crociere

The Supreme Court has issued its opinion in Krupski v. Costa Crociere, No. 09-337, a case that refines our understanding of the meaning of the term "mistake" in FRCP Rule 15(c), the rule governing the relation back of amendments. The lower courts had held that the plaintiff had not made a mistake regarding the identity of the proper party to be sued because she knew or should have known the identity of the proper party and delayed amending her complaint for months.

The Supreme Court reversed, holding that the amending party's knowledge is irrelevant to the 15(c) mistake analysis. What matters, rather, whether the party to be added knew or should have known that it should have been the party named in the action.