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Comparison of examiners’ forward citations in the United States and Japan with pairs of equivalent patent applications

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Abstract

In this study, we investigate and compare the number of examiners’ forward citations in the United States and Japan. The most effective way to do so is to compare pairs of patent applications that have equivalent content. Therefore, we propose a new method of extracting substantially equivalent pairs of US and Japanese patent applications, focusing on the equivalence of the specifications and the claims. Our results reveal that during the substantive examination, US examiners cite patent application publications (PAPs) as well as granted patent publications (GPPs), whereas Japanese examiners tend to cite PAPs only. We further examine why GPPs are frequently cited by US examiners. The most likely reason seems to be that many US examiners retain the old habit of searching and citing only GPPs, but not PAPs. The insights offered by this study could be significant for future analyses based on the number of citations, particularly in the United States.

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Notes

  1. Examiners in both the US and JP can cite any documents disclosed prior to the filing of the patent application in order to deny novelty or non-obviousness of patent applications during the substantive examination. This is based on 35 U.S.C. 102 and 103 in the US and Article 29 of the Patent Act in JP.

  2. PAPs are published under this system. See point (a) in the subsection “The effects of differences in the US and JP patent systems” in the “Results and discussion” section for a brief explanation of the Pre-Grant Publication system.

  3. This is the master documentation database of the European patent office.

  4. The definition of the INPADOC patent family is available at http://www.epo.org/searching/essentials/patent-families/inpadoc.html.

  5. In this study, we limited our analysis to the period after the introduction of the Pre-Grant Publication system in the US. Therefore, we limited US patent applications to those for which PAPs were published.

  6. This discussion is based on the experiences of the corresponding author of this study, who worked in the Japan Patent Office as a patent examiner for almost 10 years.

  7. See footnote 1.

  8. This requirement is based on Article 17bis(3) of the Patent Act in Japan. The US has almost the same requirement, based on 35 U.S.C. 112 and 132.

  9. This period was 7 years until august 2001.

  10. See Chapter 2016 of the Manual of Patent Examining Procedure published in the US. (http://www.uspto.gov/web/offices/pac/mpep/mpep-2000.pdf).

  11. We classified patent applications into five technical sectors (Chemistry, Electrical engineering, Instruments, Mechanical engineering, and Others) according to the principal IPC based on the “IPC–Technology Concordance Table” (WIPO 2013). (The data for “Others” are not shown in Fig. 3).

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Authors and Affiliations

  1. Course of Intellectual Property in Biosciences Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan

    Satoshi Yasukawa & Shingo Kano

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  1. Satoshi Yasukawa
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  2. Shingo Kano
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Correspondence to Satoshi Yasukawa.

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Yasukawa, S., Kano, S. Comparison of examiners’ forward citations in the United States and Japan with pairs of equivalent patent applications. Scientometrics 102, 1189–1205 (2015). https://doi.org/10.1007/s11192-014-1466-5

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