Prieto advised Aguas Andinas, Chile’s largest sanitation company, in the process of selling 100% of its direct and indirect stake in its subsidiary Empresa de Servicios Sanitarios de Los Lagos S.A. (ESSAL) to the Canadian company Algonquin Power & Utilities Corp. ESSAL is a publicly held corporation, holder and operator of the sanitary concessions of the Los Ríos and Los Lagos regions.