Procedural Posture

This document is the Post-Hearing Brief on Jurisdiction filed by the Respondent, the United Mexican States, in an ICSID arbitration (Case No. ARB/23/33). The arbitration was initiated by Cyrus Capital Partners, L.P. and Contrarian Capital Management, LLC under Chapter XI of the North American Free Trade Agreement (NAFTA) and the transitional provisions of Annex 14-C of the United States-Mexico-Canada Agreement (USMCA). The brief consolidates Mexico's arguments that the Tribunal lacks jurisdiction to hear the claims and that the claims are inadmissible.

Jurisdictional and Admissibility Objections

The Respondent advances a series of comprehensive objections to the Tribunal's jurisdiction, asserting fundamental defects in the Claimants' case. These objections are grounded in multiple bases, including *ratione voluntatis*, *personae*, *materiae*, and *temporis*.

First, Mexico argues a lack of consent (*ratione voluntatis*), contending that the Claimants failed to comply with the mandatory 90-day waiting period stipulated in NAFTA Article 1119 before filing their Request for Arbitration. Furthermore, the waivers submitted by the Claimants under Article 1121 are alleged to be deficient and improperly limited in scope, thereby failing to perfect Mexico's consent to arbitrate.

Second, the brief challenges the Claimants' standing (*ratione personae*), arguing they are not qualifying "investors" who have suffered loss as required by NAFTA Article 1116. Mexico posits that the Claimants are merely management entities with no direct economic interest in the underlying notes, which are held by other non-party funds. Consequently, the Claimants cannot bring claims on behalf of third parties who actually hold the economic interests. The brief also contends that the alleged investment fails to meet the objective criteria of an investment under Article 25 of the ICSID Convention, specifically the requirements of a contribution to the host state's economy and the assumption of investment risk (the *Salini* test).

Third, Mexico asserts a lack of subject-matter jurisdiction (*ratione materiae* and *ratione temporis*). It argues that the Claimants do not hold a "legacy investment" as defined by USMCA Annex 14-C, because the underlying notes were acquired after NAFTA was terminated. Critically, the Respondent contends that Annex 14-C does not extend the substantive protections of NAFTA beyond its termination date; it merely provides a three-year procedural window for claims concerning breaches that occurred while NAFTA was in force. This interpretation, Mexico notes, is consistently supported by the subsequent practice of all three USMCA parties (Canada, Mexico, and the United States), which constitutes an authentic interpretation under the Vienna Convention on the Law of Treaties. The brief also raises a *ratione temporis* objection on the grounds that the Claimants acquired the notes after the alleged measure (a domestic injunction) was issued.

Mootness and Relief Sought

Finally, the Respondent argues that the claim for denial of justice is inadmissible because the domestic injunction that forms the basis of the claim has ceased to exist, having been revoked by Mexican courts. This development, Mexico contends, renders the entire arbitration moot. Based on these cumulative jurisdictional and admissibility failures, Mexico requests that the Tribunal dismiss the claims in their entirety and award all costs of the arbitration in its favor.