The notion of 'investment' in international investment arbitration.

Already since several decades, arbitral platforms have been established to allow investors to bring claims directly against the host State of their investment. The most prominent institution is ICSID, the International Centre for Settlement of Investment Disputes. These institutions have experienced a marked increase in their caseload over the past 15 years and seem to be flourishing. However, there are still contentious concepts for which a precise definition is lacking. A surprising example is the notion of ‘investment’ itself. The fact that this notion is a crucial factor in the determination of the jurisdiction of an arbitral tribunal that is established to rule on ‘investment’ disputes makes defining it much more than a mere theoretical exercise. This research project aims to review the different interpretations of this concept by analysing the practice and and development of the relevant legal regimes pertaining in the hope of contributing to a more efficient and predictable arbitral practice.