Social network analysis of patent infringement lawsuits

Using patent lawsuit information, we develop a method to identify companies with a significant legal influence on the technologies used in their industry. We construct a patent-infringement lawsuits graph, using the data from intellectual property lawsuits between companies, and analyse the level of influence of companies by computing the network centrality of each company in the graph. To illustrate the practicality of our method, we apply the proposed method to analyse the patent influence of well-known companies in the smartphone industry. The results of our empirical analysis are well matched to the current smartphone market status — for example, Apple, Nokia and Samsung are identified as the most important companies, which lead the smartphone technology and market. This shows that the proposed approach can be used to evaluate and manage patent portfolios even using a relatively small amount of patent lawsuits data.

► The patent influence of companies can be measured by analysing their patent disputes.
► A systematic methodology to identify each company's patent portfolio is proposed.
► A case study for patent-infringement cases in the mobile phone industry is provided.
► Implications for corporate R&D policy and decision makers on patents are derived.