The United States Supreme Court has held that an action brought on behalf of a class may be appealed upon expiration of the named plaintiffs substantive claim even though the class certification has been denied.
United States Parole Commission v. Geraghty, 445 U.S. 388 (1980).
Thomas F. Smida,
Constitutional Law - Mootness - Personal Stake - Class Actions,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol19/iss4/7