Environmental innovation and international migration of inventors

We study the effects of migrant inventors on environmental innovation activity for sustainable development. We focus on inventor migration from (to) countries specializing in patent applications grouped into eight environment-related technology domains. Using the novel dataset created by Pellegrino et al. (2023) and a weighting scheme to construct the migrant inventor variables, we create accurate measures of the stock of immigrant and emigrant inventors. We find a positive and significant impact of migrant inventors on the green innovation activity of both receiving and sending countries. The results indicate that environmental innovation rises with R\&D expenditure, international trade, air pollution (CO2 emissions), and natural disasters. Our results are robust to the instrumental variable approach, a falsification test for the main explanatory variables, a dynamic model specification (path dependency hypothesis), a different set of lagged control variables, and inventors' data tracked over time.