2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/221832We propose an abstract approach to coalition formation that focuses on simple merge and split rules transforming partitions of a group of players. We identify conditions under which every iteration of these rules yields a unique partition. The main conceptual tool is a specific notion of a stable partition. The results are parametrized by a preference relation between partitions of a group of players and naturally apply to coalitional TU-games, hedonic games and exchange economy games.21 pages. To appear in International Game Theory Review (IGTR)Computer Science and Game Theorytext