The Ninth Circuit recently held that personal jurisdiction defenses as to absent class members should be raised at the class-certification stage. Moser v. Benefytt, Inc., 8 F.4th 872 (9th Cir. 2021), vacated a district court order that certified two nationwide classes despite the defendant’s objection that the district court lacked personal jurisdiction as to the claims of absent class members. The district court had deemed the argument waived because the defendant had failed to raise it on a motion to dismiss. The Ninth Circuit disagreed, explaining that the defendant could not have asserted a personal jurisdiction defense against the claims of unnamed putative class members at the pleading stage, and that the first opportunity to raise such a defense arose when a motion for class certification was filed. (There was no dispute that the district court had specific personal jurisdiction as to the named plaintiff’s claims.) The ruling provides important guidance to defendants on when such personal jurisdiction defenses should be asserted.