As businesses reorganize around platforms, shared digital infrastructures are becoming increasingly important to build competitive advantage. Ecosystems of open software and hardware technologies, known as “technology commons,” are increasingly dominating the lower levels of digital infrastructures (i.e., below the user-interface level). To leverage technology commons for platform advantage, businesses need to play the “digital commons ecosystem game.” We highlight the motivations and four strategic maneuvers for playing this game, present a five-level strategic roadmap for mastering the game and provide recommendation on who should play it.