Dual Citizenship in the European Union: trends and analysis (2010-2020) This report aims to clarify the current state of affairs regarding dual citizenship in 28 Member States of the European Union.5 Firstly, the variations of dual citizenship regimes within the EU-28 will be outlined, including the interactions of these regimes in ‘citizenship constellations’. Secondly, developments regarding dual citizenship policies in the EU-28 between 1 January 2010 and 1 January 2020 will be discussed, as well as relevant developments regarding citizenship of the European Union. Throughout this report, the typology of the GLOBALCIT Modes of Acquisition and Loss of Citizenship Database will be used.6 1.1 Varieties of restrictions to dual citizenship in the European Union Restrictions of dual citizenship in the European Union can be divided into three categories, namely 1) requirements to renounce the original citizenship upon the acquisition of citizenship (Globalcit modes of acquisition A05-A27), 2) provisions stipulating the (automatic or notautomatic) loss of citizenship upon the acquisition of a foreign citizenship (Globalcit mode of loss L05), and 3) provisions stipulating the (automatic or non-automatic) loss of citizenship upon the retention of a foreign citizenship (Globalcit mode of loss L06). In addition to that, a small number of countries outside the European Union restrict acquisition of citizenship at birth if the child has already obtained another citizenship at birth, but this is not the case in any of the EU Member States.7 It must be noted that, in the context of the European Union, the concept of EU citizenship is of paramount importance. On the basis of Art. 9 TEU and Art. 20 TFEU, persons holding the citizenship of an EU Member State are also citizens of the European Union and therefore enjoy a ‘bundle of rights’ in all EU Member States.8 EU citizenship status springs from national citizenship, the demarcation of which has in principle remained a member state competence. Nevertheless, the European Court of Justice ruled in Micheletti that it is for each Member State, having due regard to EU law, to determine its citizenry and, consequentially, the citizenry of the European Union.9 As this report focuses on domestic citizenship law, the concept of EU citizenship will play a limited role in this report. 5 On 1 January 2020, the following 28 countries were EU Member States: Austria, Belgium, Bulgaria, Croatia, Republic of Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom. 6 See: <https://globalcit.eu/acquisition-citizenship/>, last accessed on 20 June 2020; <https://globalcit.eu/acquisition-citizenship/>, last accessed on 20 June 2020; Vink, M. and Van der Baaren, L., GLOBALCIT Modes of Acquisition and Loss of Citizenship Dataset Codebook, Version 1.00, Globalcit, San Domenico di Fiesole: European University Institute (forthcoming). 7 Examples are China, where a child born abroad of Chinese citizen parents who have settled abroad does not automatically acquire Chinese citizenship if he or she also acquires a foreign nationality at birth (Art. 5 Nationality Law of the People’s Republic of China) and Panama, where a child born abroad of Panamanian citizen parents can only acquire citizenship if he or she takes up residence in the country (Art. 13 Political Constitution of the Republic of Panama). 8 See inter alia: Bauböck, R. (ed), Debating European Citizenship, Cham: Springer International Publishing 2019; De Groot, G. R. and Luk, N. C., Twenty years of CJEU jurisprudence on citizenship, German Law Journal, Vol.15, No. 5, 2014; Guild, E., The Legal Elements of European Identity: EU Citizenship and Migration Law, The Hague: Kluwer Law International 2004; Kochenov, D. (ed), EU Citizenship and Federalism, Cambridge: Cambridge University Press 2017; Maas, W. (ed), Multilevel Citizenship, Philadelpia: University of Pennsylvania Press 2013; Margiotta, C., Vonk, O., “Nationality law and European citizenship: the role of dual nationality”, in: Talani, L.S. (ed), Globalisation, Migration, and the Future of Europe: Insiders and Outsiders, London: Routledge Press 2012. 9 Case C-369/90, Micheletti and others v Delegación del Gobierno en Cantabria, ECLI:EU:C:1992:295 (Micheletti), par. 10; H. U. Jessurun d’Oliveira, Case C-369/90, MV Micheletti and others v. Delegacion del Gobierno en Cantabria, Judgment of 7 July 1992, Common Market Law Review, Vol. 30, 1993. . See also: Case 2 RSCAS/GLOBALCIT-Comp. 2020/4 - © 2020 Author