This document is the partial dissenting opinion of Arbitrator Christian Vidal-León, issued in the context of a request to consolidate two arbitrations (FM1 and FM2) initiated by an investor against Mexico under NAFTA Chapter Eleven. The arbitrator dissents from the majority's decision in the Non-Consolidation Order, which denied the Respondent's request for consolidation pursuant to NAFTA Article 1126(2).

Disagreement on the 'Efficiency' Analysis

The core of the dissent lies in a fundamental disagreement with the majority's analysis of whether consolidation would be "in the interests of fair and efficient resolution of the claims." Arbitrator Vidal-León argues that the majority's conclusion is predicated on a legally flawed premise regarding the procedural status of the second arbitration (FM2). The majority determined that the Claimant had effectively withdrawn its FM2 claims "with prejudice," thereby rendering consolidation moot as there were no longer parallel claims to consolidate.

In contrast, the dissenter contends that, under the applicable 2022 ICSID Arbitration Rules, the FM2 claims remain pending. He reasons that a unilateral withdrawal of claims "with prejudice" is not a recognized procedural mechanism after a request for arbitration has been registered, particularly where the respondent has objected to discontinuance, as Mexico did. Allowing such a withdrawal would, in his view, improperly undermine the Respondent's procedural rights under Rule 56(1) (right to object to discontinuance) and Rule 49(2) (right to seek an award on the merits in case of a claimant's default). Consequently, the "non-consolidation scenario" envisioned by the majority does not reflect the actual legal situation.

Implications for the Consolidation Test and 'Fairness'

Arbitrator Vidal-León posits that because the FM2 claims are still legally pending, a proper efficiency analysis under NAFTA Article 1126(2) would have to consider the significant risks of duplicative proceedings, increased costs, and conflicting decisions that arise from running two separate arbitrations. This, he suggests, would likely lead to the conclusion that consolidation is the more efficient path.

On the question of fairness, the arbitrator concludes that the balance tilts in favor of consolidation. He characterizes the Respondent's request for consolidation as an exercise of an explicit right granted by the NAFTA treaty. Conversely, he views the Claimant's strategy—attempting to introduce the FM2 claims as ancillary claims into the FM1 proceeding while simultaneously seeking to unilaterally terminate the FM2 arbitration—as a circumvention of the ICSID Rules, which generally require party agreement for the consolidation of proceedings. Therefore, he finds the Respondent's treaty-based approach to be the fairer of the two alternatives for resolving all claims before a single tribunal.