297It follows, in particular, that the role of ‘ringleader’ played by one or more undertakings in a cartel must be taken into account in setting the fine, in so far as undertakings which have played such a role must therefore bear a special responsibility by comparison with other undertakings (Case C-298/98 PFinnboard v Commission [2000] ECR I-10157, paragraph 45; Mayr-Melnhof v Commission, paragraph 180 above, paragraph 291).