The measurements and determinants of patent technological value: Lifetime, strength, breadth, and dispersion from the technology diffusion perspective

Elucidating and prejudging the patent technological value (PTV) is an important issue in the field of technology innovation and Patentometrics. However, most studies adopt a static perspective to define and evaluate it according to forward citations (FC), which disregards the time attribute and evolution process and may cause some contradictions or ambiguities among findings. Through combing the time and number attributes of FC, this study recommends a four-dimensional index (technology lifetime, strength, breadth, and dispersion) from the standpoint of patented technol-ogy diffusion, a dynamic evolution process. By considering patent data from three technology fields -graphene, information and communication, bio-medicine -as samples, we examine the multidimensional characteristics of PTV and further adopt Cox and multiple regression analysis to determine its influential factors. The finding shows that PTV is multi-dimensional and the four-dimensional index is helpful to explain the differentiation effects of different influential factors. Furthermore, six internal factors (intrinsic and evolutionary) that influence PTV in varying degree are identified and verified. Specially, as for intrinsic factors, only backward citation influences all four-dimensional index with a positive impact on technology lifetime and strength, and negative impact on breadth and dispersion. Technology field can negatively affect strength and breadth, but positively affect dispersion. Delivery term can only affect technology lifetime negatively. As for evolutionary factors, patent legal lifetime influences all four-dimensional index with a nega-tive impact on technology lifetime and strength, and positive impact on breadth and dispersion. Forward citation exerts a positive impact on breadth and strength while a negative impact on technology lifetime and dispersion. Transfer number exerts a positive impact on technology life-time, but a negative influence on dispersion. This study not only offers a four-dimensional index to signify the technological value of a patent, but construes the contradictions or ambiguities about the relationships between the influential factors and PTV. Besides, the influential factor model is also helpful to prejudge the technological value of patents at different stages after the granting.