Sources of law
Union law is mentioned in the first position in lit a of para 1. When is the UPC required to apply Union law? The UPC was established by the UPCA which is a piece of international law and is not part of Union law. That makes the UPC an international court. However, the Member States established it—at the level of international law—as a court common to them which, pursuant to Arts 1(2) and 21 UPCA, is part of their respective national judicial systems. As part of the judicial system (Art 21 UPCA) of the CMSs—by an order under international law—and by reason of an express provision in Art 20 UPCA, the Court fulfils the obligation of the CMSs to apply Union law. Since the Court is a ‘court common to a number of Member States’, ‘it is situated within the judicial system of the European Union’, which is why ‘its decisions’ are subject to ‘mechanisms capable of ensuring the full effectiveness of Union law’. This wording—used in Opinion C-1/09 of the Court of Justice with reference to the Benelux Court of Justice—is also appropriate with reference to the UPC. Although it is integrated into the judicial systems of the Member States in a different way compared with the Benelux Court of Justice, it is a ‘court common to the Member States’, and it is only based on that connecting factor that the Benelux Court of Justice is ‘situated within the judicial system of the European Union’. The ‘mechanisms capable’ are expressly confirmed in Arts 21–23 UPCA.