Do inventors talk to strangers? On proximity and collaborative knowledge creation

•Innovation is an increasingly collaborative activity: this paper explores the characteristics of the collaborations between inventors.•Organisational proximity is a key feature of co-patenting teams together with cultural/ethnic diversity and ‘unconstrained’ social networks.•Geographic proximity is linked to co-patenting only when it interacts with other proximities.•Innovation policies should, rather than focus on spatial clustering, facilitate the formation of open and diverse networks. This paper examines the characteristics of the collaborations between inventors in the United Kingdom (UK) by looking at what types of proximities – geographic, organisational, cognitive, social, and cultural–ethnic – between inventors are prevalent in partnerships that ultimately lead to technological progress. Using a new panel of UK inventors this paper provides an analysis of associations between these ‘proximities’ and co-patenting. The results show that while collaboration within firms, research centres and universities remains crucial, external networks of inventors are key feature of innovation teams. The analysis shows that external networks are highly dependent on previous social connections, but are generally unconstrained by cultural or cognitive factors. Geographical proximity is also weakly linked with external networks. Our results suggest that innovation policies should, rather than focus on spatial clustering, facilitate the formation of open and diverse networks of inventors.