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Quarterly Journal of Economics Vol. 130 No. 1 2015

Patents and Cumulative Innovation: Causal Evidence from the Courts *

Alberto Galasso1; Mark Schankerman2

1 University of Toronto · 2 London School of Economics and Political Science

open access

Abstract

Cumulative innovation is central to economic growth. Do patent rights facilitate or impede follow-on innovation? We study the causal effect of removing patent rights by court invalidation on subsequent research related to the focal patent, as measured by later citations. We exploit random allocation of judges at the U.S. Court of Appeals for the Federal Circuit to control for endogeneity of patent invalidation. Patent invalidation leads to a 50% increase in citations to the focal patent, on average, but the impact is heterogeneous and depends on characteristics of the bargaining environment. Patent rights block downstream innovation in computers, electronics, and medical instruments, but not in drugs, chemicals, or mechanical technologies. Moreover, the effect is entirely driven by invalidation of patents owned by large patentees that triggers more follow-on innovation by small firms.

DOI
10.1093/qje/qju029
Volume
130
Issue
1
Pages
317-369
Language
en
Sources
bibtex:phds-export.bib openalex crossref

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