Balancing Investor Protection and Sovereignty: The Evolution of BITs and ISDS in International Public Investment Law

This paper explores the evolution of Bilateral Investment Treaties (BITs) and the Investor–State Dispute Settlement (ISDS) mechanism within international public investment law. It traces their historical development, core legal principles, and the growing tension between investor protection and state sovereignty. The study examines key reforms in new-generation treaties, including efforts to enhance regulatory space, clarify standards like fair and equitable treatment (FET), and promote sustainable development. Through detailed treaty and case law analysis, the paper highlights how the investment regime is transitioning toward a more balanced and legitimate framework.