Recent empirical evidence has shown that firm’s innovation behavior exhibits high persistency but not much is known about potential contingencies affecting the degree of persistence. This paper focuses on the role of the local knowledge environment and asks how local knowledge spillovers...

We investigate the stability of cooperative relationships between inventors and consequences for the characteristics and patent productivity of the respective regional innovation systems (RIS). The empirical analysis is for nine German regions over a period of 15 years. We find a rather high...

Using patent citation data for the U.S., we test whether knowledge spillovers in biotechnology are sensitive to distance. Controlling for self-citation by inventor, assignee and examiner, cohort-based regression analysis shows that spillovers are local but that distance is becoming less...