Intellectual search of patent text is an important task that requires knowledge of the subject area. In today's world, when the growing pace of technological innovation is already leading to fundamental changes, with entering the fourth industrial revolution Industry (4.0), the development of artificial intelligence and the virtual economy, the analysis of patent documentation is becoming an increasingly important task, therefore, traditional approaches to text analysis are insufficient for comprehensive study of the patent text. This article discusses methods of patent document analysis, including topic identification, text segmentation, information display, feature selection, clustering, and summary selection, etc. The described methods can be used to better understand the relationships between different technologies and their priorities and to assess competition and opportunities for their use in the market. Also considered are the main challenges and problems associated with the analysis of patent documentation, such as the limited amount of data and the heterogeneity of their structure. The article's conclusions can be useful not only for the linguistic analysis of patent documentation, but also for researchers, engineers, managers and other specialists working in the field of innovation and technology development.