Federal Rule of Civil Procedure 23(f) gives federal courts of appeals authority to permit interlocutory appeals from orders granting or denying motions to certify a class. The rule leaves it murky, however, whether an order partially decertifying a class is appealable under Rule 23(f). In a brief opinion by Judge Posner, the Seventh Circuit has now held that it is.
In Matz v. Household International Tax Reduction Investment Plan (pdf), the court ruled that “an order materially altering a previous order granting or denying class certification is within the scope of Rule 23(f) even if it doesn’t alter the previous order to the extent of changing a grant into a denial or a denial into a grant.” The court reasoned that “[t]his is best seen by imagining that rather than altering a class that the court had already certified the district judge had at the outset certified a narrower class than proposed by the plaintiff. That order would have been appealable by either party . . . . We don’t see why it should make a difference that the order modifying the class requested by the plaintiff came later. The difference is between one order and two orders that accomplish the same thing.”