Patents and Knowledge Diffusion: The Effect of Early Disclosure

We study how the timing of information disclosure affects the diffusion of codified technical information. On November 29, 2000, the American Inventors Protection Act (AIPA) reduced the default publication time of patents at the United States Patent and Trademark Office (USPTO) to 18 months. We analyze the effects of this change by means of a regression discontinuity design with time as an assignment variable and a complementary difference-in-differences analysis. Our study shows that information flows from patents measured by forward citations, increased. Interestingly, the degree of localization within geographic boundaries remained unchanged and technological localization even increased moderately. Moreover, the effect of early disclosure on citations from patents filed by patent attorney service firms is particularly strong. These results imply that knowledge diffusion stemming from speedier disclosure of technical information is confined to the existing attention scope and absorptive capacity of inventors and organizations.