Similarity Analysis of Patent Claims Using Natural Language Processing Techniques

Claims typically found at the end of a patent document are one of the key elements of a patent and define the boundaries or scope of protection conferred by a patent. Claims of related patents also need to be read and reviewed carefully by an inventor or a patent attorney at the time of drafting a patent application. We present a method and a tool to do a claim similarity analysis between two different patents based on natural language processing techniques. The technique proposed in this paper relies on computing similarity between two claims based on syntactic and semantic matching of the natural language text describing the claims. We present results of experiments performed on patent claim data obtained from patents published on Google patents website. The motivation behind the research presented in this paper is to build patent processing tools to increase the overall productivity of a patent analyst or a patent attorney while doing claims infringement, validity and quality analysis.