Ecosystem governance has gained significant traction in strategy research. Contrary to the prevailing focus on complementors, we examine why the ecosystem leader continues or terminates suppliers’ ecosystem membership. Departing from the view of buyer-supplier relationships, we address the multilateral interdependence inherent in an ecosystem, unveiling the overlooked production complementarities between upstream and downstream actors. Based on a sample of 320 Apple’s suppliers between 2012 and 2020, we find that the ecosystem leader is less likely to terminate its relationship with suppliers who have formed alliances with complementors. This effect diminishes as the ecosystem leader faces role-based and activity-based alignment challenges, arising from its technological dependence on suppliers and suppliers’ environmental uncertainty, respectively. The study contributes to research on multilateral interdependence, ecosystem governance, and alignment challenges. vvvvvv
