Federal Rule of Civil Procedure 23(f) provides that:  ‛A court of appeals may in its discretion permit an appeal from an order of a district court granting or denying class action certification under this rule if application is made to it within ten days after entry of the order.“  The ten-day time limit is jurisdictional.  
The plaintiffs in Jenkins v ...
Federal Rule of Civil Procedure 23(f) provides that:  ‛A court of appeals may in its discretion permit an appeal from an order of a district court granting or denying class action certification under this rule if application is made to…