Can a plaintiff amend his complaint in order to convert the lawsuit into a class action, to add his union local as a defendant in the fiduciary duty claims?

The district court did not abuse its discretion when it denied the plaintiff's motion to amend his complaint in order to convert the lawsuit into a class action, to add his union local as a defendant in the fiduciary duty claims, and to state a claim under the Taft-Hartley Act. The plaintiff now concedes that these amendments would be useless unless we reversed the district court's judgment on the age discrimination or breach of fiduciary duty claims. Our affirmance of that part of the judgment, therefore, requires that we affirm the district court's denial of the plaintiff's motion to amend, at least with respect to the first three of his four proposed amendments. See Foman v. Davis, 371 U.S. 178, 182, 83 S.Ct. 227, 230, 9 L.Ed.2d 222 (1962).