In a case in which an employer-plaintiff filed an unfair labor practice charge against a union, and the National Labor Relations Board issued a Notice of Hearing under section 10(k) of the National Labor Relations Act, which directs the Board to hear and determine disputes concerning unfair labor practice charges, the District Court's grant of summary judgment to plaintiff is reversed where the District Court lacked subject matter jurisdiction to vacate an interlocutory decision of the Board issued under section 10(k).