What happened with the El Tambor (La Puya) project and the Kappes arbitration against Guatemala?

El Tambor–Progreso VII Derivada (gold; San José del Golfo and San Pedro Ayampuc; the peaceful 'La Puya' resistance) was suspended by the Supreme Court (CSJ) in 2016 for lack of consultation,… confirmed by the Constitutional Court (CC) in 2020. Kappes, Cassiday & Associates claimed US$499 million from Guatemala before ICSID (CIADI, case ARB/18/43); the award of 23 December 2025 rejected the claim in full and ordered the investors to reimburse US$379,940.76 in procedural costs to Guatemala (date confirmed in Jus Mundi). The lesson: the Foreign Investment Law (Decree 9-98) opens the door to arbitration, but the treaty did not rescue a project without consultation or social peace.