国際比較の観点からみた日本の大学発特許の特徴
Japanese University Patents: Characteristics from an International Comparison

塚田 尚稔, 池内 健太
Naotoshi Tsukada, Kenta Ikeuchi

日本知財学会誌Vol.22 No.3 p.51-63 (2026-3-20)
Journal of Intellectual Property Association of Japan Vol.22 No.3 p.51-63 (2026-3-20)

＜要旨＞
本研究はPATSTAT データを用いて2005 年以降の大学名義の特許を国際比較し，日本の大学特許の特徴を分析した．日本の大学特許は件数では米国や中国に劣るものの，被引用件数上位特許の国内比率は高く，技術的に重要な知識を生み出している．化学・材料など工学系に強みがあり，生命科学系に集中する米国や欧州とは分野構成が異なる．産学共同出願の比率が高く，企業との共同研究の成果が特許化されている．学術文献引用は相対的に少ないが，これは分野構成や連携形態の違いも影響していると考えられる．また，国際出願件数は限定的だが，個別には質の高い国際出願特許もあり，選択的な出願戦略が示唆される．量的拡大よりも質の高い大学特許の戦略的な活用や，企業への技術移転と知識波及効果のバランスを考慮した知財政策が重要と考えられる．
<Abstract>
This study conducts an international comparison of university-owned patents filed since 2005 using PATSTAT database and analyzes the characteristics of Japanese university patents.　Although the number of Japanese university patents is smaller than that of the United States and China, they account for a relatively high domestic share of highly cited patents, indicating their contribution to technologically significant knowledge creation.　Japanese universities demonstrate strengths in engineering-related fields such as chemistry and materials science, in contrast to the concentration of university patents in the life sciences in the United States and Europe.　Japan is also characterized by a high proportion of university-industry joint patents, reflecting the patenting of research outcomes derived from collaborative research with firms.　While citations to academic literature are comparatively limited, this pattern is likely due to differences in technological fields and collaboration structures.　Moreover, although the number of international patent applications is modest, some individual international filings are of high quality, suggesting the adoption of a selective filing strategy.　These findings highlight the importance of intellectual property policies that emphasize the strategic utilization of high-quality university patents over quantitative expansion, while balancing technology transfer to firm with broader knowledge diffusion.

＜キーワード＞
大学特許, 引用指標, 国際比較, 産学連携
<Keywords>
University Patents, Citation Index, International Comparison, University-industry Collaboration