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General Science and Engineering Indicators
R&D Investment Patterns
S&E Workforce Development
Knowledge Output
S&E Articles Published by Selected Country
Number of Triadic Patent Families by Nationality of Inventor
Citations to U.S. Articles by USPTO Patents

Selected Education Indicators
High School Completion Patterns
High School Teachers
Higher Education Enrollments

Selected Global Marketplace Indicators


U.S. patent citations to science and engineering articles rose rapidly through the late 1990's, with the largest increases seen in citations to academic articles in the biomedical and clinical medicine fields.

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Why is this indicator important?

  • The citation of S&E literature in U.S. patents indicates the extent to which academic research across S&E fields fosters innovation across sectors.

Key Observations

  • Academic-authored articles in biomedical research and clinical medicine accounted for 41% of the increase in total citations across all fields between 1995 and 2004.
    • Growth in citations to both biomedical and clinical medicine research occurred primarily in the late 1990s, and citations to research in both fields declined between 2001 and 2004.
  • Citations to industry-authored papers, the second largest source, declined from 25% in 1995 to 21% in 2004.

Related Discussion

  • Patents referencing S&E articles nearly tripled between 1990 and 2001, increasing from approximately 6,000 in 1990 to over 20,000 in 2003 (SEI 2006 Table 5-26).
  • The average number of citations per patent increased from 0.33 per patent in 1990 to 1.56 in 2003 (SEI 2006 Appendix Table 5-65).
  • The bulk of U.S. patents citing scientific literature were issued to U.S. inventors, who accounted for 65% of these patents in 2003, a share disproportionately higher than the 51% of all U.S. patents issued to U.S. inventors (SEI 2006 Table 5-26).
  • The counts in the above chart do not control for patents that cite the same S&E article(s) and may overestimate the degree of "transfer" from scholarly output to potential commercial application.