Abstract
World Intellectual Patent Organization (WIPO) indicates that realizing patent information well can reduce the 60% research time and save 40% research budgets. Therefore, sufficient patent retrieve and detailed patent analysis can clarify the patent protection situation and the obstacle, and then further help for the global understanding on the whole technical domain. Now patent retrieve and analysis is worked by patent engineer manually, which costs a lot of efforts. As the rapid increasing of patent documents, the expense is more awful. In this study we simulate the claim explanation, taking apart the claim into four parts: elements, the relations between elements, steps, and the relations between steps. Then, this information was used to build machine readable formats, which is easy for comparison or showing structure graphically. At last, we propose a way to compare the similarity of two steps. The similarity value show patent engineers which steps are similar and increase the efficiency on claim explanation. The comparison algorithm splits the steps to many features, matches these features into different feature classes, then calculates the similarity value in each class by the corresponding calculating way. Finally sum the similarity value of all matched features with different weight to get the similarity value of two steps. The experimental results show that our similarity comparison way is better than BLEU at the steps comparison of patents.