The Decision on Jurisdiction in Theodoros Adamakopoulos and Others v Republic of Cyprus is now three years old. Alongside Marcelo Kohen’s dissent, this decision triggered much discussion regarding (i) the alleged incompatibility of the relevant bilateral investment treaties (bit s) vis- à- vis the European Union (EU) treaties and (ii) the implications of mass claims brought under icsid Rules. With an award looming on the horizon, it is necessary to address a different aspect of the decision: the majority’s qualification of certain bonds and other indirect expressions of such assets as an ‘investment’ under Article 25 (1) of the icsid Convention. This article will argue that the Tribunal majority’s analysis – relying as it does on a series of incompatible decisions – manifestly fails to establish that contingent convertible Bank of Cyprus and Laiki Bank bonds held by Claimant bondholders qualify as an ‘investment’ under the icsid Convention. The Tribunal majority thereby undermined jurisdiction ratione materiae for a significant class of Claimants, creating an opening for adverse Annulment Committee review upon release of the final award.