The series of actions carried out by the first farmers during the manufacturing of their pottery, an essential part of their economic package, can act as a powerful proxy of their spatial and temporal trajectories. This proxy is based on the demonstration in social anthropology of an unequivocal link between the chaîne opératoire of a ceramic and the social identity of its producer. Based on the reconstruction of pottery forming practices from seventeen sites associated with the emergence and early diffusion of Neolithic ways of life in the Western Mediterranean (Impressed Ware, c. 6050-5600 BCE), the present study reveals the co-occurrence of two distinct technical entities in Impressed Ware contexts: (1) one identified to the east of the Apennine Mountains, which implements a chaîne opératoire already observed in Balkan early agricultural contexts around 6100 BCE (pottery formed by superimposed coils); (2) the other identified to the west of the Apennines Mountains, which implements a chaîne opératoire that had never been identified in other archaeological contexts (pottery formed by juxtaposition of “spiralled patches”). The anthropological significance of this major technical frontier in Impressa contexts is assessed in the light of new Bayesian date modelling and of an array of recent economic and bio-archaeological data. Our results strongly support the coexistence of two different social networks in Impressed Ware contexts, and consequently, of two distinct groups of farmers, one of which shows filiations with the Balkan Early Neolithic, whereas the filiations of the other yet remain unknown. The clear spatial exclusion, over the long term, of these two social groups deeply questions the concept of a continuous migration path of early farmers in the Western Mediterranean.