Marine stations have long been explored by science and technology studies (STS) and the humanities as boundary objects between the field and the lab. Moreover, through their position, they embrace two domains which have been separated by the modern organization of knowledge – sea and society – not only epistemically, but also physically. In contrast to time-limited marine expeditions or pure laboratory work, marine stations enact “science with their feet in the water” while situated within concrete local societies. Therefore, many marine stations provide multiple ways of valuating the relation between the sea and society. However, in an era of considerable polarization regarding a sustainable future for coastal communities, valuating marine knowledge is a socially complex endeavour. Based on a two-month ethnography of the world’s oldest existing institution of this kind, the Station Marine de Concarneau in Brittany, France, the paper discusses its practical enactment of heterogeneous values associated with marine knowledge. The paper, first, introduces the Concarneau station, its particular research profile and local exposure. Second, an experimentalist approach based on pragmatism and STS is explored in order to rethink current research on the valuation of socio-marine cohesion. Third, three types of valuating marine knowledge through heterogeneous collaborations at the station are explored: a) socio-material, b) socio-epistemic and c) socio-disciplinary. Finally, the paper deduces the importance of marine stations for inter- and transdisciplinary collaboration within the global transformation of sea-society relations.