Patent citations as determinants of grant and opposition: case of European wind power industry

ABSTRACT

The grant of a patent and filing of an opposition are important events in the lifecycle of a patent. This paper tests the influence of backward citations on the likelihood of a patent grant and, if any, an opposition. Since all citations are not alike, detailed analysis is done by assessing type, nature and origin of citations in European search reports and, where needed, international search reports. The nature of citations, blocking or non-blocking, is found to have a significant impact on the likelihood of a patent being granted. The effect of citations originating during different stages of patent pendency is also explored in this study. For practitioners, the study provides a landscape of the European wind industry that is characterised by popularity of the PCT route, dearth of non-patent citations and dominance of bigger actors. For academics, the study offers novel opportunities to utilise citation based indicators.

KEYWORDS:

• Patent citations
• patent opposition
• patent value
• wind power

Acknowledgements

We would like to thank Lappeenranta University of Technology for funding this research as part of patent studies in climate change mitigation technologies. We are also grateful for the insights provided by two anonymous referees.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Rahul Kapoor received his Master’s degree in Industrial Engineering and Management from Lappeenranta University of Technology, Finland in 2013. He is currently working on his doctoral thesis related to patent value indicators at Lappeenranta University of Technology. His areas of interests are intellectual property management, competitive intelligence, patent and business research.

Anmol Mohan is graduate from National Institute of Technology, Allahabad and a certified Data Scientist from Johns Hopkins University (via Coursera.org). He has 6 years of industry experience is Data Mining and Business Analytics. His research interests include Pattern Recognition, Machine Learning and Artificial Intelligence.

Dr Matti Karvonen works as a Researcher at Technology Business Research Center (TBRC). He received his Master degree from Joensuu in 1999 and Lappeenranta in 2004, followed by the PhD degree from Lappeenranta University of Technology in 2011. His research interests are in technology management, industry evolution, convergence and patent analysis methods.

Professor Tuomo Kässi has a M.Sc. degree in technical physics and in economics. He wrote his doctoral thesis in Industrial Engineering and Management. Dr Kässi has worked in research and development, sales and marketing, and as director of machinery production and consultant in industry some 25 years before entering his academic career. His research interests are in technology management, innovation and strategy.

Notes

1. Our wind industry data revealed an average grant lag of 4.7 years and average opposition lag of 5.5 years.

2. We have used the phrases ‘prior art’, ‘backward patent citations’, ‘backward patent references’, sometimes just ‘citations’, interchangeably in this paper.

3. For more details about European and international citations for EPO patents please refer to Webb et al. (2005).

4. PCT applications can also be filed at the EPO. In this case EPO generates the international search report too. See Table 6 for detailed shares of filing routes in our sample.

5. Some firms like ABB are financially big conglomerates but they feature in the list of ‘small players’ because they own fewer wind power patents than other players.

6. This result is different from Harhoff and Reitzig (2004), 472, who found positive relationship between X citations and incidence of opposition for biotechnology and pharmaceutical patents.

7. Some efforts have been made to use patent characteristics as determinants of opposition outcomes by Sterlacchini (2016).