The PVC II case law on the principle of ‘ne bis in idem’ prevents the reopening of proceedings if the EU Courts have already ruled on the substance of the case. • In the Soliver and Aalberts cases, the EU Courts annulled the respective Commission decisions in their entirety while, at the same time, finding that the undertakings concerned had violated EU competition law. • This article challenges the PVC II case law by arguing that the Commission could reopen proceedings against Soliver and Aalberts because in such cases the EU Courts, which only carried out a review of legality, could not render a ‘final judgment’ within the meaning of the principle of ‘ne bis in idem’.