For iura novit curia to be applicable, a normative basis rooted in the applicable law must be established. Although various normative foundations could justify its application, some are more suitable than others. This chapter will examine various normative foundations and assess their suitability. Furthermore, the principle’s scope of application is shaped by the broader policy objectives that underpin the investment protection regime. Specifically, iura novit curia promotes three key policy goals in this context: ensuring accurate decision-making, contributing to the development of international investment law, and upholding the equality of arms between the disputing parties.