Using Patent Citation to Explore Knowledge Flow between Different Industries

R&D and innovation are important activities in firms. During these activities, spillover and diffusion of knowledge are generated. Especially in this era of information and the Internet, the speed of knowledge flow is faster, the costs are lower and the paths are more diverse. In the past year, most of the studies about spillover or knowledge flow were focused on one industry or one industrial park because the cross industries´ knowledge flow was limited. That is, researchers discussed knowledge flow between firms within one specific industry. Since Internet technology began sweeping the world, the conception and boundaries of industry blurred. The phenomenon was called digital convergence. This mean that some technologies and knowledge can be applied to different industries or the firms of different industries can enter the same markets and become competitors. Therefore, this paper will discuss the knowledge flow of different industries. Among many indicators of measuring spillover and knowledge flow, patent citation is a mature and objective indicator. This paper is positioned in the field of business methods technology, and draws upon the largest patent database in the world - USPTO as its source of information. The purposes of this paper are: 1. to examine the knowledge flow of business methods that have any significant difference between and within different industries; 2. to detect the direction of knowledge flow between the different industries; and 3. to propose some suggestions of knowledge flow in the field of business methods technology.