What Does ODRL Mean? A Cross-Level Ontological Grounding of Permissions, Prohibitions, and Duties in UFO-L

2026-06-23

AI Summary

This work addresses the limited semantic expressiveness of existing ODRL policy evaluators, which output verdicts without capturing normative positions, authority structures, or the power to declare violations. To overcome this, the authors propose a cross-layer design principle that distinguishes behavioral from capability-level normative positions and, for the first time, maps ODRL rules to legal relation reificators in the UFO-L ontology. The approach introduces eight legal positions—expanding from the original two—to explicitly model the sanctioning nature of prohibitions and resolve ambiguities between open- and closed-world interpretations of permissions. Furthermore, it formalizes the power–subjection relationship underlying violation declarations. Leveraging the UFO-L ontology and formal semantics, the framework is axiomatized and mechanically verified in Isabelle/HOL, and evaluated using the Vampire, E, and Z3 solvers on 39 benchmark problems, significantly broadening ODRL’s semantic coverage and achieving a unified formal account of normative positions and authority structures.

Abstract

ODRL policy evaluators produce verdicts, but say nothing about the normative positions a policy brings into existence, the authority structures those positions presuppose, or who holds the power to declare a norm violated. We formulate the Cross-Level Design Principle: any normative language with violable, consequential norms requires both conduct-level positions (Permission, Duty, Right, No right) and competence-level positions (Power, Subjection, Immunity, Disability). Applying this to ODRL, we establish that prohibition is sanctioned (violation possible and consequential), that permission is underspecified across its behaviour parameter (open vs. closed world), and that the formal semantics covers achievement obligations only. We ground ODRL in UFO-L, mapping each activated rule to a simple legal relator and extending coverage from two to eight legal positions; violation-declaration authority, implicit in every existing evaluator, becomes an explicit Power-Subjection pair. All axioms are mechanically verified in Isabelle/HOL and across a 39-problem benchmark under Vampire, E, and Z3.

Problem

• ODRL
• normative positions
• authority structures
• policy evaluation
• legal relators

Innovation

• ODRL
• UFO-L
• normative positions
• cross-level design principle
• mechanical verification