Analysing Patent Terms and Citations to Determine the Value of Gene Therapies


  • Peter Van Dongen Netherlands Patent Office
  • Zainab Noor El Hejazi Free (VU) University Amsterdam, The Netherlands
  • Eric Claassen Athena Institute, Free (VU) University, Amsterdam, The Netherlands



1, gene therapies, 2, patent citations and 3, market value & capitalization


Gene therapies hold great promise for treatment of diseases but so far their market authorisation has been limited. This paper describes the development of patented gene therapies in the sector of life sciences and health.  It was found that the annual number of patented gene therapies increased significantly till the year 2005.  A cluster analysis of gene therapies patented in 1995 shows that:  a) more than eighty percent has been renewed for more than fifteen years (fifty three per cent till the maximum patent term) and b) fifty per cent of the patents have been licensed. There is a statistically significant correlation between the numbers of citations in future patent applications by third parties and the number of years of patent renewals.

A case study of the patent EP 0833934 of biotechnology start- up Crucell demonstrates that the number of citations by third companies to this patent even predicts the companies’ market capitalization. This research yielded evidence that the number of patent citations can be used as indicator to determine the value of gene therapies. Such information is of relevance for both the patentee and investors.

Author Biographies

Peter Van Dongen, Netherlands Patent Office

Researcher and Engineer at the Research and promotion department of the Netherlands Patent Office

Zainab Noor El Hejazi, Free (VU) University Amsterdam, The Netherlands


Eric Claassen, Athena Institute, Free (VU) University, Amsterdam, The Netherlands



Torrance, A.W. (2014). Gene concepts, gene talk and gene patents. Miss. J. Of Science and Technology (2010), 11 (1), 157 - 191

Alberts, B., Johnson, A., Lewis, J. Raff, M. Roberts, K. and Walter, P. (2012). Molecular Biology of the Cell, Garland Science, p.

Editorial (1999). Nature (401), 517-8

Personal communication B. Leufkens, CBG MEB (2016)

Dutfield, G. (2006). DNA patenting: implications for public health research, WHO bulletin, 84 (5), 388- 392

Jensen, K. and Murray, F. (2005). Intellectual Property Landscape of the Human Genome. Science, 310 (5746), 239 - 240

Castle, D. ed. (2006). The role of Intellectual Property Rights in Biotechnology Innovation, Edward Elgar, Northampton, MA, USA p. 101- 152

Soini, S., Ayme, S., and Matthijs, G. (2008). Patenting and licensing in genetic testing: ethical, legal

and social issues, European Journal of Human Genetics, 16, 510 - 50

Regents of the University of California (2001). Recombinant DNA Research at UCSF and Commercial Application at Genentech, Boyer's UCSF Laboratory

Patzelt, H. and Brenner, T. eds. (2008). Handbook for bio tech entrepreneurs. Springer. New York, p.193- 207

Chapter 10

Zucker, L.G., Darby, M.R. and Amstrong, J.S. (2002). Commercializing Knowledge: University Science, Knowledge Capture and Firm Performance in Biotechnology, Management Science, 48 (1), 149 - 170

Zechendorf, B. (2011). Regional Biotechnology- The EU biocluster study, Journal of Commercial Biotechnology, 17, 209-217,

Pugatch, M.P., Torstensson, D. and Chu, R. (2012). Taking stock: How global biotechnology benefits from Intellectual Property Rights, Pugatch Consilium, 57 p.

OECD (2011). Intellectual Assets and Innovation,

Gambardella, A., Harhoff, D. and Verspagen, B. (2008). The value of European patents. European Management Review 5, 69-84

Harhoff, D., Scherer, F.M. and Vopel, K. (2003). Citations, family size, opposition and the value of patent rights, Research Policy. 32, 1343- 1363

Harhoff, D., Narin, F., Sherer, F.M. and Vopel, K. (1999). Citation Frequency and the value of patented inventions. The Review of Economics and Statistics. 81 (3), 511-515, doi/10.1162/003465399558265

Magazzini, L. , Pammolli, F. And Riccaboni, M. (2008). Patent value and R&D Competion, DRUID Summer Conference Copenhagen

Hall, B.H, Jaffe, A. and Trajtenberg, M. (2005). Market value and patent citations. Rand Journal of Economics. 1- 49

Hall, B.H., Thoma, G. and Torrisi, S. (2007). Market value of patents and R&D; evidence from EU firms. NBER.

Hall, B., Jaffe, A. B, and Trajtenberg, M. (1998). Patent Citations and Market Value, NBER

Gilroy, B.M., Brandes, W. and Volpert, T. (2003). Economic implications of Intellectual Property Rights for the Biotechnology sector, A comparative analysis of the European – Japanese Situations,

Narin, F., Noma, E. and Perry, R. (1987). Patents as indicators of corporate technological strength. Research Policy 16, 143-153

Carpenter, M.P, Narin, F. and Woolf, P. (1981). Citation Rates to Technologically Important Patents. World Patent Information. 3 (4) 160-163

Trajtenberg, M. (1990). A penny for Your Quotes: Patent Citations and the Value of Innovations. The RAND Journal of Economics. 21 (1), 172-187

Fallaux, F.J., Hoeben, R.C. Bout, B., Valerio, D. Van der Eb, A.(1995). EP0833934 Packaging Systems of human recombinant adenovirus to be used for gene therapy.

Hawk IP. (2012). What is EPODOC and what is DOCDB?

Munari, F., and Oriani, R. (eds.). (2011). The economic valuation of patents: Methods and Applications. Edward Elgar, Cheltenham, UK ; Northampton, p. 169- 199

Blume, S.S. (2013). Medical innovations: Their diffusion, adoption and critical interrogation, Sociology Compass, 7 (9), 726-737,

Rogers, E.M. (2003). The Diffusion of Innovations. MacMillan Publishing C. Inc., New York, p.271- 307

Kers, J.G., Van Burg, E. Stoop, T. and Cornel, M.C. (2014). Trends in Genetic patent applications; the

commercialization of academic intellectual property, European Journal of Human Genetics 1-5,

OECD (2009). Biotechnology statistics,

Kaufman (2012). Start- up act for the States, act.pdf

Anecdotal data from interviews with Crucell ex- IPR manager and inventors (2014)

Hoeben, R.C. (2001), ‘Van kwaad tot beter’ over virussen, vectoren en gentherapie. Rede uitgesproken bij de aanvaarding van het ambt van hoogleraar in de Genoverdracht aan de Universiteit Leiden (in Dutch)

Pardo, R., and Calvo, F. (2006). Are Europeans really antagonistic to biotech? Nature Biotechnology, 24(4), 393–395.

Graff, G.D., Philips, D., Lei, Z. Oh, S. and Nottenburg, C. (2013). Not quite a myriad of gene patents. Nature Biotechnology, 31(5), 404-410,

Editorial (2013). A Victory for Genes, Nature Medicine, 19, 792

Lawrence, S. (2007). Biotech patents still strong, Nature Biotechnology, 25 (12), 1341





Intellectual Property Management