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...

This paper explores several characteristics of patents in the biotechnology field, comparing and contrasting them to patents in other fields of research. We find that biotechnology patents face a longer lag between application and grant date, and their secrecy would be heavily affected if...

Using patent citation data for the U.S., we test whether knowledge spillovers in biotechnology are sensitive to distance, and whether that sensitivity has changed over time. Controlling for self-citation by inventor, assignee and examiner, cohort-based regression analysis shows that physical...

Network analysis shows a stable network between states, but a changing environment between individual actors, with a growing importance of connectedness. The popular maxim that everyone is connected by six degrees of separation is tested with surprising results