Knowledge spillovers from superstar tech firms: the case of Nokia

Do workers hired from superstar tech firms contribute to better firm performance? To address this question, we analyse the effects of spillovers from Nokia in the context of a quasi-natural experiment: the closure of Nokia’s mobile device division and the massive labor movement it implied. We apply a two-stage difference-in-differences approach with heterogeneous treatment to estimate the causal effects of hiring former Nokia employees. We do not find strong evidence of a positive causal role of former Nokia workers on firm performance in terms of employment, value added, and net sales, and even less so on labor productivity.