Complementarities, Network Effects, and the Antitrust Puzzle of Platform M&A

Network effects are central to both the success of digital platforms and the competition concerns. Large platforms have relied on mergers and acquisitions (“M&A”) to expand their ecosystems, integrate technologies, and consolidate user bases. While such deals may accelerate innovation and improve services, they may also lock in end and business users to incumbents’ ecosystems and stifle competition. We argue that network effects are not monolithic, and link five types of complementarit