This chapter discusses the impact of CJEU copyright case law on national copyright regimes, even beyond the wording of EU directives as transposed into national legal systems. To this end, it focuses on the UK and, following a discussion of what immediate changes the departure from the EU and the EEA (Brexit) would have (also with regard to issues of exhaustion), it explores to what extent case law of the Court of Justice of the European Union (CJEU) has changed UK copyright law. EU decisions have had an impact in areas such as: copyright subsistence, subject matter categorization, primary/accessory liability, standard of infringement, exceptions and limitations, and enforcement (with particular regard to website blocking jurisprudence). Overall, this chapter shows the legacy of CJEU case law, and how pervasive the impact of such case law is.