Comparison of IPC and USPC Classification Systems in Patent Prior Art Searches

摘要

Patent classification systems are used to help scrutinize patent applications for possible violations of the novelty and non-obviousness/inventive steps of a patentability test. There are several different patent classification systems in use today, each with a different underlying philosophy and approach. We compare the two most widely-used patent classification systems -the IPC and USPC - and examine their ability to help re-rank patents based on similarity. We observed a significant improvement in MAP, Recall@100, and nDCG when using these systems to re-rank our retrieved document set, demonstrating their overall utility in patent searches.