Dynamic Aspects of OPJK Legal Ontology Zhisheng Huang 1 , Stefan Schlobach 1 , Frank van Harmelen 1 , Nuria Casellas 2 , and Pompeu Casanovas 2 1 Vrije Universiteit Amsterdam, The Netherlands {huang, schlobac, frankh}@cs.vu.nl 2 Universitat Autonoma de Barcelona, Spain {nuria.casellas, pompeu.casanovas}@uab.es Abstract. The OPJK (Ontology of Professional Judicial Knowledge) is a legal ontology developed to map questions of junior judges to a set of stored frequently asked questions. In this paper, we investigate dynamic and temporal aspects of one of the SEKT legal ontologies, by subjecting the ontology OPJK to MORE, a multi-version ontologies reasoning Sys- tem. MORE is based on a temporal logic approach. We show how the temporal logic approach can be used to obtain a better understanding of dynamic and temporal evolution of legal ontologies. 1 Introduction SEKT is a European project on developing Semantically Enabled Knowledge Technologies 1 [10]. The aim of SEKT is to develop and exploit semantically- based knowledge technologies in order to support document management, con- tent management, and knowledge management in knowledge intensive work- places. Specifically, SEKT aims at designing appropriate utilities to users in three main areas: digital libraries, the engineering industry, and the legal do- main, providing them with quick access to the right pieces of information at the right time. The SEKT Legal Case Study was based on the development of the proto- type Iuriservice 2 , a web-based application that will provide access to Spanish judges to a repository of judicial practical experience, stored in the form of question-answer pairs. A set of surveys provided the quantitative and quali- tative data necessary not only to assess the context of users (newly recruited judges in Spain) and their specific needs with regard to the technology under development, but also to gather the practical experience needed for the repos- itory [7]. In particular, these data gave insight on institutional, organisational, and individual constraints that could either facilitate the introduction of SEKT technologies within the judicial units. Iuriservice was designed as a result of 1 http://www.sekt-project.com/ 2 The prototype is developed by the Institute of Law and Technology (IDT-UAB, In- telligent Software Components S.A. (iSOCO), with the collaboration of the Spanish Judicial School and the Spanish General Council of the Judiciary (SEC2001-2581- C02-01).