**Nathan de Arriba-Sellier** is a PhD researcher, specialized in EU financial law. He is affiliated to the Erasmus Center for Economic and Financial Governance (ECEFG) and Leiden University's Europa Institute. Prior to 2019, he was a PhD fellow of Leiden-Delft-Erasmus's European Research Centre on Economic and Financial Governance (EURO-CEFG). Nathan's PhD research focuses on the interplay between national and EU authorities in financial supervision. The home/host system, and its implications for European financial sueprvision, is particularly at the core of his research. This led him to conduct research visits at Queen Mary University of London in 2018 and Duke Law School in 2019, thanks to the sponsorship of Professors Rosa M. Lastra and Steven L. Schwarcz, respectively.  His research interests cover a wide array of legal issues related to finance and the environment, particularly financial regulation, monetary policy, green finance and climate litigation.  Prior to his present position, Nathan clerked for the EU law unit of Conseil d'Etat, France's highest administrative court and legal advisor to the government. In 2015, he was a Summer Research Fellow at Stanford Law School where he conducted research on the influence of U.S. law on European financial regulatory reforms. Before that, he was an assistant to the French General Consul in Hamburg, Germany. He also used to serve as vice-president in charge of student life at his alma mater, University Jean Moulin Lyon 3. Nathan holds an LL.M in EU Law from College of Europe (Bruges) as well as an LL.M. in International and European Business Law from the University of Vienna. He graduated valedictorian with a 'Maîtrise' in European law from the University Jean Moulin Lyon 3 after a year at University Hamburg where he was enrolled as part of the Erasmus exchange programme. During his bachelor, he studied French public law, German law and U.S. law.