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 study reveals significant and growing localization
effects of knowledge spillovers at both intra- and international levels
after the 1980s. Increased localization effects have been accompanied
by greater heterogeneity across states and industries. The results are
robust to various methods of proxying the existing geography of
knowledge production