Information Systems Group

― Knowledge Representation and Reasoning

Boris Motik

University Lecturer; Non-Tutorial Fellow, Somerville College


I am interested in developing algorithms and techniques necessary for realizing advanced applications in the Semantic Web. In particular, my research is focused around the ontology language OWL — an ontology language with firm theoretical roots in the description logic (DL) family of knowledge representation formalisms. I developed theoretical foundations for various extensions of DLs and OWL, such as an integrity constraint language, integration with various rule-based formalisms, and constructs for the representation of arbitrarily connected structures. I have also been working on proof-theoretic aspects of DLs and OWL, and have so far implemented two reasoners for OWL.

In my PhD, I developed algorithms for reasoning in OWL by reusing database technologies. I implemented these techniques in the KAON2 reasoner. The German company ontoprise GmbH is currently using KAON2 in a commercial setting.

Recently, I have been working on a new reasoner HermiT. This reasoner is based on a novel reasoning algorithm based on hypertableau, which allows HermiT to process certain ontologies that have traditionally been quite "hard".


Before coming to Oxford, I worked in the Information Management Group, School of Computer Science, University of Manchester. I got my PhD from the University of Karlsruhe under supervision of Prof. Rudi Studer. While in Karlsruhe, Germany, I was employed at the Research Center for Information Technologies (FZI). I speak English, German, and Croatian, so feel free to send me e-mails in any of these languages.


Selected as one of "2008 AI's 10 to Watch" by the IEEE Intelligent Systems magazine

The Cor Baayen Award 2007 by the European Research Consortium for Informatics and Mathematics (ERCIM) for "a most promising young researcher in computer science and applied mathematics"

Best Paper award at the 2005 International Semantic Web Conference for my paper "On the Properties of Metamodeling in OWL".

Recent Publications

Completeness Guarantees for Incomplete Ontology Reasones: Theory and Practice. Bernardo Cuenca Grau‚ Boris Motik‚ Giorgos Stoilos and Ian Horrocks. In Journal of Artificial Intelligence Research (JAIR). Vol. 43. Pages 419−476. 2012.

A Novel Approach to Ontology Classification. Birte Glimm, Ian Horrocks, Boris Motik, and Giorgos Stoilos. Journal of Web Semantics: Science, Services and Agents on the World Wide Web, 2012.

Representing and Querying Validity Time in RDF and OWL: A Logic-Based Approach. Boris Motik. Journal of Web Semantics: Science, Services and Agents on the World Wide Web, 12–13:3–21, 2012.


Boris Motik


University Lecturer, Non-Tutorial Fellow, Somerville College


ConDOR, REOL, REQUIEM, HermiT, Score!, Optique

Contact Information

+44 (0)1865 283544

Room 308, Wolfson Building, Parks Road
Oxford OX1 3QD


CV in PDF format

HermiT reasoner


Awards at the ORE 2013 workshop

MORe, HermiT and ELK, three OWL reasoning systems developed in the Knowledge Representation and Reasoning (KRR) group, have been awarded at the OWL Reasoner Evaluation Workshop (ORE 2013).

OWL Reasoner Evaluation Workshop (ORE 2013)

The KRR group co-organises the 2nd edition of the OWL Reasoner Evaluation Workshop (ORE), collocated with DL 2013 workshop.

Best paper prize at SWAT4LS'12

Doctoral Student Despoina Magka's paper entitled 'Ontology-Based Classification of Molecules: a Logic Programming Approach' has received the best paper prize at the 2012 Semantic Web Applications and Tools for Life Sciences workshop [more information].

Boris Motik awarded EPSRC Early Career Fellowship

Boris Motik was recently successful in gaining an EPSRC Early Career Fellowship. The 5 year project, MaSI3: A Massively Scalable Intelligent Information Infrastructure, focuses on Ontology-based Data Management Systems (ODMSs). These are a new kind of data management system specifically designed to deal with complex data, by using natural language queries often across multiple relevant sources [more information].

KRR member wins 'doctoral award' from University of Manchester

Yavor Nenov's PhD thesis "Computability of Euclidean Spatial Logics" has been awarded the Best Thesis Prize of the School of Computer Science at the University of Manchester [more information].

Ian Horrocks (KRR group leader) elected to Academia Europaea

Ian Horrocks has been elected to join Academia Europæa, an eminent organization for European scholars. Academia Europæa was founded in 1988 and has over 2000 members, including around 40 Nobel Laureates [more information].

KRR member wins 'doctoral award' from Spanish university

The Jaume I University of Castellon (Spain) has awarded a "Premio extraordinario de doctorado" (roughly translated as a Extraordinary Doctoral Award) to Ernesto Jimenez-Ruiz who is now a postdoctoral researcher at Oxford's Department of Computer Science [more information].

OAEI 2012: Matching Large Biomedical Ontologies

The KRR group organises the Large Biomedical Ontologies track within the Ontology Alignment Evaluation Initiative.