This document is the Counter-Memorial of the Respondent, the United Mexican States, filed in an ICSID arbitration (Case No. ARB/20/13) initiated by Espíritu Santo Holdings, LP and L1bre Holding, LLC under Chapter XI of the North American Free Trade Agreement (NAFTA). The submission presents Mexico's comprehensive rebuttal to the Claimants' Memorial, contesting the claims on jurisdiction, merits, and quantum. Mexico raises fundamental jurisdictional objections. It challenges jurisdiction *ratione personae*, arguing that the Claimants' ultimate beneficial owners are Mexican nationals, rendering the dispute domestic in nature and outside NAFTA's protections. Furthermore, Mexico contests jurisdiction *ratione materiae*, asserting that the alleged investment was not made in accordance with Mexican law. The Respondent contends the entire project was predicated on illicit acts, including collusion with public officials and the use of allegedly falsified documents, which divests the investment of treaty protection. On the merits, Mexico denies any breach of its NAFTA obligations. It argues that no expropriation occurred because the underlying "concession" for a digital taximeter system was legally non-existent, having been granted through a flawed process by a government entity (Semovi) that lacked the legal authority to do so—a position later confirmed by Mexican domestic courts. Mexico refutes any violation of the Fair and Equitable Treatment (FET) standard, arguing that no specific, unambiguous representations were made to create legitimate expectations. The claim of a National Treatment violation is also dismissed, with Mexico arguing that its development of a public-service taxi application ("Mi Taxi") is not comparable to the Claimants' commercial venture and was a legitimate exercise of its sovereign functions. Mexico strongly contests the Claimants' damages claim, which is based on a Discounted Cash Flow (DCF) analysis. The Respondent characterizes this valuation as entirely speculative and inappropriate for a pre-operational enterprise with no history of revenue. Should liability be established, Mexico posits that the appropriate measure of damages would be limited to verifiable sunk costs, not hypothetical future profits. Ultimately, Mexico requests the Tribunal to dismiss all claims for lack of jurisdiction and/or on the merits, and to award costs in its favor.