Exploring Dual Nationality in International Law: From Historical Perspectives to Investor-State Arbitration

p class="MsoNormal"This study explores the complex issue of dual nationality in investor-state arbitration, a topic of increasing relevance due to rising migration and foreign direct investment. As dual nationals frequently initiate investor-state arbitrations, tensions have emerged regarding their rights under International Investment Agreements (IIAs) and public international law. The study begins with a historical analysis of dual and multiple nationality, focusing on how nationality serves as a crucial link for individuals and private entities to access international legal rights. It then examines the evolution of doctrines governing dual nationality, including the rule of non-responsibility and dominant and effective nationality. Subsequent chapters analyse the jurisdictional challenges faced by investor-state tribunals in cases involving dual nationals and review tribunal decisions on this issue. The study concludes by highlighting the need for greater consistency and clarity in international law concerning dual nationality in investor-state arbitration.