This Decision addresses a post-award application by the Claimant, Veolia Propreté SAS, pursuant to Article 49(2) of the ICSID Convention, requesting a supplementary decision on a question allegedly omitted from the Tribunal’s Award of 26 September 2025. The central issue was whether the Tribunal had failed to rule on the Claimant’s claim for “Historical Losses Interest”—interest on damages accruing from the date of breach until the date of assessment (31 December 2011)—or whether the Award’s provision for pre-award interest commencing only from the date of assessment constituted an implicit rejection of such a claim.

The Claimant contended that Historical Losses Interest was a distinct head of claim, separate from the Pre-Award Interest awarded by the Tribunal, and that the failure to address it constituted a clear omission susceptible to correction under Article 49(2). The Respondent, the Italian Republic, argued that the Tribunal had made a deliberate and explicit choice to award interest only from the date of assessment, thereby fully resolving the matter of interest and rendering the Claimant's request an impermissible attempt to revise, rather than supplement, the Award.

The Tribunal found the request admissible and granted it on the merits. It determined that the parties and their experts had consistently treated Historical Losses Interest and Pre-Award Interest as two separate concepts throughout the arbitration. The Tribunal concluded that its reasoning in the Award concerning interest pertained exclusively to Pre-Award Interest and that it had, in fact, omitted to render a decision on the claim for Historical Losses Interest. Rejecting the Respondent’s arguments, the Tribunal affirmed its jurisdiction to decide the omitted question, noting that any resulting increase in the quantum of damages is a permissible consequence of a supplementary decision.

In its operative decision, the Tribunal supplemented the Award by granting the Claimant’s claim for Historical Losses Interest. However, it declined to apply the same interest rate (EURIBOR + 2%) used for Pre-Award Interest. Citing the positive and higher EURIBOR rates prevalent during the 2007-2011 period, the Tribunal applied a reduced spread of 1% (EURIBOR + 1%), calculating the additional amount due to the Claimant as €9,279,749. Further, finding the Respondent’s opposition to the request unmeritorious and having unnecessarily increased costs, the Tribunal issued an adverse costs order, requiring the Respondent to bear its own legal expenses and reimburse 50% of the Claimant’s legal expenses for the supplementary proceeding.