Abstract
Semantic technologies offer a powerful foundation for building policy engines that can interpret, negotiate, and enforce data usage rules in a consistent and interoperable way. As such, by leveraging semantic standards, the W3C-standardised Open Digital Rights Language (ODRL) can be used to transform policies from static legal checkboxes into machine-understandable agreements that evolve with real-world needs. In this tutorial, we show how ODRL—backed by the under-development ODRL semantics specification—enables deterministic evaluation of complex, contextual policies, supporting more trustworthy and adaptive data exchanges. Participants will be introduced to the concept of policies, and in particular to ODRL policies, and then get hands-on experience in managing policies, as well as in the inner workings of ODRL evaluation. The tutorial covers how to create policies with ODRL, the basics of ODRL 2.2 semantics, and how policies should be evaluated, as well as the required inputs and resulting output necessary to implement ODRL evaluators. Moreover, participants get an introduction to existing implementations and advice from the core people driving the W3C ODRL Community Group work, and will have time during the tutorial to make the first steps in applying it to their areas of interest.
Learning goals
- Participants know the motivation and vision for publishing data with usage policies
- Participants know what is a policy and a policy language
- Participants know the technical basis of policies and how they relate to other semantic technologies
- Participants can create and manage their own policies
- Participants understand the basics of the semantics of ODRL 2.2 and know how policies should be evaluated
- Participants know the architecture of an ODRL evaluator and understand the importance of having a test suite
- Participants understand the required inputs and resulting output necessary to implement an ODRL evaluator
- Participants make their first steps in using an ODRL evaluator for a small project of their choosing or other practical applications
Tutorial Materials
Programme Schedule
| Time | Session | Speaker |
|---|---|---|
| 09:00 - 09:05 | Introduction to the tutorial | Organisers |
| 09:05 - 09:45 | Introduction to policies, policy languages and ODRL | Prof. Víctor Rodríguez-Doncel |
| 09:45 - 09:50 | Short Break | — |
| 09:50 - 10:30 | Introduction to Formal semantics of ODRL policies | Dr. Nicoletta Fornara |
| 10:30 - 11:00 | Coffee Break | — |
| 11:00 - 11:30 | Inputs and outputs of ODRL evaluators | Dr. Beatriz Esteves & Prof. Andrea Cimmino |
| 11:30 - 11:35 | Short Break | — |
| 11:35 - 12:30 | Practical applications with existing ODRL evaluator implementations | Prof. Andrea Cimmino & Wout Slabbinck |
Organisers & Speakers
This tutorial will be presented and organised by a group of researchers that co-chair and/or actively contribute to the W3C ODRL Community Group:
Beatriz Esteves
Postdoctoral researcher in the KNoWS research group of IDLab, Ghent University, specialising in semantic and decentralised technologies that promote trust and transparency on the publication and sharing of (personal) data on the Web, while complying with data protection regulatory requirements.
Wout Slabbinck
PhD researcher in the KNoWS research group of IDLab, Ghent University, focused on the interoperability and enforceability of usage control policies in decentralised ecosystems.
Nicoletta Fornara
Senior Researcher and Lecturer at Università della Svizzera italiana (USI), at the Faculty of Communication, Culture and Society, where she conducts research in Autonomous Agents and Normative Multiagent Systems by using Semantic Web Technologies. She is studying the problem of defining a formal semantics for ODRL.
Further Reading and References
- Iannella, Renato, and Serena Villata. ODRL Information Model 2.2 (W3C Recommendation 15 February 2018). https://www.w3.org/TR/odrl-model/.
- Iannella, Renato, Michael Steidl, Stuart Myles, and Víctor Rodríguez-Doncel. ODRL Vocabulary & Expression 2.2 (W3C Recommendation 15 February 2018). https://www.w3.org/TR/odrl-vocab/.
- Fornara, Nicoletta, Víctor Rodríguez-Doncel, Beatriz Esteves, Simon Steyskal, Benedict Whittam Smith, and Yassir Sellami. ODRL Formal Semantics (Draft Community Group Report 16 December 2025). https://w3c.github.io/odrl/formal-semantics/.
- Slabbinck, Wout, Julián Rojas Meléndez, Beatriz Esteves, Pieter Colpaert, and Ruben Verborgh. 'Interoperable Interpretation and Evaluation of ODRL Policies'. In The Semantic Web, edited by Edward Curry, Maribel Acosta, Maria Poveda-Villalón, et al. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-94578-6_11.
- Cimmino, Andrea, Juan Cano-Benito, and Raúl García-Castro. 'Open Digital Rights Enforcement Framework (ODRE): From Descriptive to Enforceable Policies'. Computers & Security 150 (2025): 104282. https://doi.org/10.1016/j.cose.2024.104282.
- Bonatti, Piero Andrea, Nicoletta Fornara, and Andreas Harth. 'Towards a Formal Semantics of the Open Digital Rights Language (ODRL 2.2)''. ODRL and Beyond: Practical Applications and Challenges for Policy-Based Access and Usage Control (OPAL 2025), Co-Located with the Extended Semantic Web Conference 2025 (ESWC 2025), 2025. https://ceur-ws.org/Vol-3977/OPAL2025-4.pdf.
- Esteves, Beatriz, Wout Slabbinck, Yassir Sellami, Andrea Cimmino, Víctor Rodríguez-Doncel, and Ruben Verborgh. 'Capturing Requests and Context for ODRL-Based Access and Usage Control'. Joint Proceedings of the 16th Workshop on Ontology Design and Patterns and the 1st Workshop on Bridging Hybrid Intelligence and the Semantic Web (WOP-HAIBRIDGE 2025) Co-Located with the 24th International Semantic Web Conference (ISWC 2025), 2025. https://ceur-ws.org/Vol-4093/paper5.pdf.