Patents are a major asset for world companies in the knowledge-based economy. They are outputs of research and development as such and can bring a company a 20 years monopoly on its invention. As a counterpart, the content of patents — the description of the invention — is published. The resulting patent information represents the most accurate and valuable technological information freely available worldwide — a goldmine! It is mostly used to avoid infringement and check novelty ; with new visualization and macro-analysis tools — including data mining —, it can also be used to watch competitors’ innovation, discover new business opportunities and analyze the evolution of a technological field. This report is the account of an internship dealing with these tools and methods. They were used for a case study in the agrochemical field, the results of which shall launch new in-house services and contribute to the dissemination and acknowledgement of patent information.