The industrial internet of things (IIoT) has created entirely new inter-firm competitive and collaborative dynamics that focus on the supply of digital infrastructures, services and platforms for industrial users. These dynamics typically involve machinery builders, information technology suppliers and traditional technology buyers from various asset-intensive sectors. Given the global character of IIoT technology, transnationally relevant inter-firm arrangements have emerged for which we still lack a conceptually grounded understanding. This study addresses this research gap from the German perspective by combining the concepts of global value chains and complex technical systems. Empirically, we develop a multiple case study of established German firms that have provided IIoT technologies in the domain of ‘smart manufacturing.’ We investigate the firms’ evolving positions within the multi-layered IIoT stack and explore their technological dependency on global cloud-infrastructure suppliers. Second, we put the case study into the context of the recent German industrial-policy initiatives related to the discourse of ‘digital sovereignty’, which attempt to improve the positions of domestic actors vis-àvis the multi-national tech companies. Conceptually, this study offers the framework of global technological ecosystems as a new perspective on the transnational platform economy, which highlights the enabling character of global-scale digital infrastructures and acknowledges active involvement of non-firm actors in ecosystem governance.