There is considerable interest in understanding how important market frictions are in stifling the transmission of ideas from one firm to another. Although the theoretical literature emphasizes the importance of these frictions, direct empirical evidence on them is limited. We use comprehensive...

This paper examines the trends in geographic localization of knowledge spillovers via patent citations, extracting multiple cohorts of new sample US patents from the period of 1976-2015. Despite accelerating globalization and widespread perception of the "death of distance," our matched-sample...

This paper examines the trends in geographic localization of knowledge spillovers via patent citations, considering US patents from the period of 1976-2015. Despite accelerating globalization and widespread perception of the \death of distance," our multi-cohort \matched-sample" study reveals...

We analyze cross-country trends in technological progress over the period of 1980-2011 by examining citations data from almost 4 million utility patents granted by the US Patent and Trademark Office (USPTO). Our estimation results on patent quality and distance to the knowledge frontier reveal...

We examine the "home bias" of knowledge spillovers (the idea that knowledge spreads more slowly over international boundaries than within them) as measured by the speed of patent citations. We present econometric evidence that the geographical localization of knowledge spillovers has fallen over...