By Neelesh T. Moorthy
I assess whether forward citations—how often patents are cited by subsequent patents—reliably capture patent quality. A high-quality invention might lack forward citations if there are no competing, patenting firms. This introduces measurement error in using citations to measure patent value. I test whether greater competition makes forward citations better measures of patent quality, with eight and twelve-year patent renewal rates serving as my benchmark measures of patent quality. Patent data come from the manufacturing survey in Cohen, Nelson, and Walsh (2000). I conduct logit regressions of patent renewal on forward citations and the number of competitors faced by surveyed manufacturing labs. While the regression results do not support the competition hypothesis, they confirm that forward citations positively predict renewal. They also lend insight into firms’ strategic renewal decisions.
Advisors: Wesley Cohen and Michelle Connolly | JEL Codes: O31, O34