The maritime economy as a heterogeneous innovation system has ongoing relevance to the successful spatial and functional development of port city regions in Europe. A strong technological knowledge base underpins the competitiveness of maritime economy which is grounded in distinct spatial structures and proximities. The simultaneous relevance of global and local knowledge is particularly pronounced in the maritime economy through its inherent relevance to globalization and structural change. Conventional classifications embedded in the discussion of the spatialization of knowledge intensive activities and global value chains, however, limit the analysis to certain parts of the maritime cluster. This paper looks at the applicability of various discourses on knowledge generation as an interactive process, based on a comprehensive dataset derived from cooperative links within the maritime economy of northern Germany. It suggests a framework for analysis, which is activity based and focused on the concurrent presence of different dimensions of proximity across value creating systems. We explore spatial patterns by means of social network analysis, which are industry-specific and have the potential to inform efforts to increase functional as well as physical connectivity in Port City regions. The empirical analysis sets out from the individual firm as an actor seeking to optimize its location for the purpose competitiveness. It proposes an approach, which is routed in the ongoing discussion on spatial and functional dispositions for innovation activity and bridges the dichotomy of knowledge intensive services and manufacturing activities in the maritime economy.