The Linguistic Classification System (LCS) was developed at the University of Nijmegen, The Netherlands, in the course of the EC/IST projects DORO and PEKING. The LCS is a classification system based on machine learning algorithms Rocchio, Balanced Winnow and SVMLight, especially suited for the task of classifying text documents. The LCS allows different document representations (keywords with or without lemmatization, linguistic phrases), hence the L in its name.

The LCS can either be used through a Java-based API or through Web services. While the API supports the training of the categorisation system as well as the categorisation of unseen patents, the Web services currently offers functionality of categorisation. The availability of training through Web services is an objective for a future release.