Co-Patenting across European Innovation Systems (1980-2015): Methodological concerns and observed trends

This study contributes with novel insights on the phenomena of joint ownership of patents. From a methodological point of view, we show the need to consolidate co-ownership of patents between independent entities by excluding apparent joint applications of one and the same entity. Our results reveal a considerable share of around 30% ‘false positive’ co-patents for a subset of patent applications originating from 43 European countries between 1980-2015. From an empirical point of view, we map trends based on the deflated indicator, which indeed signal a growing importance of co-patenting as a tangible output of R&D collaborations, in particular since the mid-2000s, albeit with trends being highly differentiated across fields, countries and sectors. While we find that companies do not increase their (proportional) engagements in co-patenting practices, we observe sharp increases of co-patents among the patent portfolios of universities and governmental organizations. In general, besides being associated with public actors, higher co-patenting shares seem to occur relatively more in countries with less developed innovation systems. However, for some science-intensive fields, including pharmaceuticals, biotechnology and nanotechnology, we find similarly increasing co-ownership trends across all types of innovation systems, again predominantly involving actors of the public sphere. We suggest that co-patent indicators may provide intriguing novel perspectives on the configurations of collaborative R&D practices across European innovation systems. Besides viewing co-patents as reflective of joint or open business strategies and observing that they become increasingly relevant in some constellations, our findings suggest that the presence of co-patents could signal developmental trajectories on the level of technological fields (science intensive fields) and on the level of (national) innovation systems (innovation followers and moderate innovators). Public actors seem to play a crucial role in these developmental trajectories. Our observations are in line with the idea of differentiated value appropriation strategies of actors where co-patenting by companies is approached cautiously due to downward exploitation concerns resulting from shared intellectual property, which are of lesser concern among and with public actors. Yet another possibility is the supposed decline of science in corporate R&D where large companies have increasingly relied on externally generated knowledge from universities and smaller firms. Here, the observed trends where companies increasingly co-patent with universities or other governmental institutions, particularly in science-intensive fields might be signalling a trend whereby firms rely more systematically on development and commercialization of new knowledge generated in the public sector, especially when exploring novel fields. To explore this further, we assessed correlations between the co-patent sector combination index across fields with the relative specialization (RTA) of academic, governmental, company and individual patents in those fields. Whereas the public-public and public-private co-patent index is very strongly positively correlated with relative specializations of the academic and governmental sector (r ≥ 0.84***), the private-private and public-private co-patent index is negatively correlated with relative specializations of company and individual patents (r ≤ - 0.26***). This means that for public actors, co-ownership is aligned with their strengths, their relative specializations. For private actors, in contrast, co-ownership is situated in their under-specializations. Hence, these findings seem to suggest that firms strongly differentiate their (co-)ownership strategies depending on the nature of the innovative activity (exploitation versus exploration), and that (the evolution of) ownership strategies diverge sharply between private and public actors