The Clef Ip track ran for the rst time within Clef 2009. The purpose of the track was twofold: to encourage and facilitate research in the area of patent retrieval by providing a large clean data set for experimentation; to create a large test collection of patents in the three main European languages for the evaluation of cross lingual information access. The track focused on the task of prior art search. The 15 European teams who participated in the track deployed a rich range of Information Retrieval techniques adapting them to this new speci c domain and task. A large-scale test collection for evaluation purposes was created by exploiting patent citations.