Out of Sight: Patents that Have Never Been Cited
Scientometrics (forthcoming 2021), submission draft
43 Pages Posted: 16 Jul 2019 Last revised: 31 Dec 2020
Date Written: May 15, 2020
Patent citations have become an acceptable proxy for inventions’ quality. Our study offers the first systematic exploration of uncited patents. Analyzing data on all US patents issued between 1976 and 2008, we examine the ratio of uncited patents out of all patents granted each year. We find a robust pattern, consistent across technological fields, whereby the percentage of uncited patents declined between 1976 and the mid-1990s, but has been significantly increasing since then. We discuss policy implications of these findings and suggest that the ratio of uncited patents can serve as a complementary measure for evaluating the patent system.
Keywords: Uncited Patents; Patents; Patent Citations; Patent Quality; Innovation; Networks; Big Data; Negative Knowledge
JEL Classification: O3, O34
Suggested Citation: Suggested Citation