Empirical Essays in Innovation Economics

Charles Wilson-De Grazia

Research output: ThesisDoctoral Thesis

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This thesis contains three papers that contribute to the measurement and understanding of patent quality at the United States Patent and Trademark Office (USPTO), its determinants, and its effects on innovation.

Chapter 2 introduces and develops two measures of patent scope, an important
aspect of patent quality, which allows for the first large-scale analysis of patent
scope changes during the examination process. Results from this chapter show that applications with narrower incoming scope are associated with a higher probability of grant and a shorter and less intense examination period in comparison to applications with broader incoming scope. Further, the results demonstrate that the examination process itself tends to narrow the scope of patents and that changes in scope are more significant when the duration and intensity of examination is increased.

Chapter 3 reexamines prior research on USPTO examiner incentives, and concludes that increasing first-action allowance rates with seniority and experience results in lower examination quality, and thus, patent quality. This chapter identifies an examiner learning mechanism that mostly accounts for the increasing first-action allowance rate, without sacrificing examination quality. However, the results show that examination quality differs between junior and senior examiners (GS-14). This learning mechanism also reduces patent grant delay, likely benefiting innovators and firms.

Chapter 4 examines how patent validity, an aspect of patent quality, may affect
follow-on patenting decisions by both assignees and technology rivals. The results indicate that validation increases for both overall and external follow-on patenting but the results are mixed for internal follow-on patenting. The increase in follow-on patenting by rivals can be attributed to an increase in defensive patenting based on the positioning of follow-on patents in technology space after validation. The positioning of external follow-on patenting is unaffected by validation. Finally, the evidence shows that the validation effect is more prominent in complex technologies relative to discrete technologies.
Original languageEnglish
Awarding Institution
  • Royal Holloway, University of London
  • Rud, Juan Pablo, Supervisor
  • Goldmanis, Maris, Supervisor
Award date1 Jan 2020
Publication statusUnpublished - 2019


  • Patents
  • Innovation

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