Innovation by foreign researchers: relative influences of internal versus external human capital

Innovation productivity of expatriate researchers and human capital that empowers them is an important issue; however, with a scarcity of relevant data, formal empirical evidence has been limited. This paper uses a rich dataset of foreign researchers at a leading German research institution to study the drivers of their innovation productivity (measured by patents and invention disclosures). Another contribution is that we examine the relative effectiveness of internal (institution-specific) and external human capital. These findings are compared to the behavior of native researchers. Results, based on a survey sample of nearly 1000 foreign researchers and taking account of the interdependence between invention disclosures and patenting, show that internal administrative leadership positions (especially group leaders) enhanced propensities to innovate, while purely academic positions (professor or guest researcher) did not positively impact innovation. With regard to external human capital, foreign researchers who were business owners or nascent entrepreneurs were more likely to innovate. Internal (institutional) experience mattered more than industry experience. Doctoral degrees seemed relatively more effective for patenting than for invention disclosures. No significant gender differences in innovation productivity were found. In contrast, while many of the influences were similar for domestic researchers, they experienced positive innovation spillovers from being directors, but domestic female researchers faced special innovation challenges. Finally, domestic professors, unlike foreign professors, did not experience negative tendencies towards innovation.