In January 2000 , ADELA was a party in a lawsuit seeking an injunction and annulment of the HCRH exploration concessions . In September of that year , the Costa Rican Constitutional Court ruled in ADELA 's favor , and granted an annulment of the four-block HCRH concession . The Court 's ruling was based on International Labor Organization Convention 169 , " Concerning Indigenous and Tribal Peoples in Independent Countries , " to which Costa Rica is bound . The Court later modified the ruling in November 2000 , however , and nullified only those blocks affecting indigenous territory
Convention 169
Indigenous and Tribal Peoples Convention, 1989
Acción de Lucha Anti-Petrola