Automatic IPC Encoding and Novelty Tracking for Effective Patent Mining.

Abstract

Accurate classification of patent documents according to the IPC system is vital for the interoperability between different patent offices and for the prior art search task involved in a patent application procedure. It is essential for companies and governments to track changes in technology in order to asses their investments and create new branches of novel solutions. In this paper, we present our experiments from the NTCIR-8 challenge to automate paper abstract classification into the IPC taxonomy and to create a technical trend map from it. We apply the k-NN algorithm in the classification process and manipulate the rank of the nearest neighbours to enhance our results. The technical trend map is created by detecting technologies and their effects passages in paper and patent abstracts. A CRF-based system enriched with handcrafted rules is used to detect technology, effect, attribute and value phrases in the abstracts. Our experiments use multi patent databases for training the system and paper abstracts as well as patent applications for testing purposes, thus characterising a cross database and cross genre task. In the subtask of Research Papers Classification, we achieve a MAP of 0.68, 0.50 and 0.30 for the English and 0.71, 0.50 and 0.30 for the J2E subclass, main group and subgroup classifiers respectively. In the Technical Trend Map Creation subtask, we achieve an F-score of 0.138 when detecting technology/effect elements in patent abstracts and 0.141 in paper abstracts. Our methodology provides competitive results for the state of the art, with the majority of our official runs being ranked within the top two for both trend map (papers) and IPC coding. That said we see room for improvements especially in the detection of technologies and attributes elements in abstracts. Finally, we believe that the subtask of Technical Trend Map Creation needs to be adjusted in order to better produce a patent map. The classification system is available online at http://pingu.unige.ch:8080/IPCCat.