The W3C Web Ontology Language (OWL) is playing an important role in an increasing number and range of applications, and is the focus of research into tools, reasoning techniques, formal foundations and language extensions. This level of experience with OWL means that the community is now in a good position to discuss how OWL be applied, adapted and extended to fulfil current and future application demands.

The aim of the OWL:Experiences and Directions Workshop series is to establish an international forum for the OWL community, where practitioners in industry and academia, tool developers and others interested in OWL can describe real and potential applications, share experience and discuss requirements for language extensions/modifications. The workshops aim at bringing all these groups together in order to pool their expertise, measure the state of need against the state of the art, and set an agenda for research and deployment in order to incorporate OWL-based technologies into new applications.

The OWLED Workshop series is organised by the OWLED Steering Committee, who are responsible for carrying out policy determined at OWLED business meetings, and otherwise assisting the organizers of OWLED workshops.


The first OWLED Workshop was held in Galway, Ireland, on November 11-12 2005, just after ISWC-2005. The workshop gathered a significant representation of theoreticians, tool builders, vendors, users and customers of OWL-based technologies in both industry and government organizations. At the workshop, the attendees identified some deficiencies and infelicities in OWL and decided to propose an extension of the language with a set of novel features, grounded on recent theoretical advances in logic-based Knowledge Representation and motivated by different application needs. It was agreed that this extension, called OWL 1.1, should go forward to W3C as a Member Submission, and the builders of many of the most widely used Semantic Web tools, such as RACER, FaCT++, Pellet, Protégé and Swoop expressed a commitment to support the new features in the near future.

The second OWLED Workshop was held in Athens, Georgia, USA, on November 10-11 2006, just after ISWC-2006. The workshop again gathered a significant representation of theoreticians, tool builders, vendors, users and customers of OWL-based technologies in both industry and government organizations. After reviewing the OWL 1.1 Member Submission, it was agreed that this should be the starting point for a new W3C Working Group whose goal would be to deliver a W3C Recommendation based on OWL 1.1. Prototypical implementations of OWL 1.1 tools were also demonstrated, including FaCT++, Pellet, Protégé and Swoop.

The third OWLED Workshop was held in Innsbruck, Austria, on 6-7 June 2007, in parallel with ESWC-2007. The workshop coincided with the announcement of the announcement of the W3C OWL WG, chartered to turn the OWL 1.1 Member Submission into a W3C recommendation. At the workshop it was decided to start a number of Task Forces, where members of the OWL community can interact to gather information on, requirements for, and designs of additions to the OWL language.

The fourth OWLED Workshop, an interim OWLED to fill the long gap between OWLED 2007 and OWLED 2008, was held in the Washington, DC, USA metropolitan area, on 1-2 April 2008, adjacent to the second face-to-face meeting of the W3C OWL WG. At the workshop it was decided to set up a Wiki for the OWLED community.

The fifth OWLED Workshop was held in Karlsruhe, Germany, on 26-27 October 2008, with the Seventh International Semantic Web Conference (ISWC 2008), just after the fourth face-to-face meeting of the W3C OWL WG. At the workshop there was discussion on how to push Description Graphs into the mainstream of OWL.

The sixth OWLED Workshop was held 23-24 October 2009, in conjunction with the Eighth International Semantic Web Conference (ISWC 2009).

The seventh OWLED Workshop was held 21-22 June 2010, in conjunction with the 2010 Semantic Technology Conference.

The eigth OWLED Workshop was held 5-6 June 2011, in conjunction with the 2011 Semantic Technology Conference.

The nineth OWLED Workshop was held 27-28 May 2012, in conjunction with the 2012 Extended Semantic Web Conference.

The tenth OWLED Workshop was held 26-27 May 2013, in conjunction with the 2013 Extended Semantic Web Conference.

The papers presented at most OWLED workshops can be accessed as CEUR workshop proceedings. Currently there are CEUR volumes for OWLED 2005, OWLED 2006, OWLED 2007, OWLED 2008 DC, OWLED 2008, OWLED 2009, OWLED 2010. OWLED 2011. OWLED 2012.

General Workshop Organization

The basic idea at OWLED workshops is to have a venue where interaction is not only encouraged, but actively encouraged. The best venues for OWLED are ones that encourage the participants to congregate in a single small area for coffee breaks and lunch.

The reviewing schedule for OWLED workshops is as tight at it can be, with papers due about three months before the workshop. The workshop accepts most papers, screening for relevance and comprehensibility. Reviewing is at a level suitable for a workshop, not a conference—constructive criticisms are welcome, but the workshop accepts a wide variety of types of papers, including theoretical results, language and feature designs both syntactic and semantics, tool descriptions, survey results, and position papers. Especially welcome are reports from user communities on how they use OWL or what they need from OWL.

Some papers are presented as full presentations (of only 15 minutes) and some papers are presented as short advertisements (less than 5 minutes) for posters. Each session ends with a discussion period of about 15 minutes. Posters are presented during coffee breaks.

Links to OWL:Experiences and Directions Workshops