Project news

LegalRuleML Core Specification V1.0 OASIS Standard published

The specification for representing legal norms and rules is now an OASIS Standard.

OASIS is pleased to announce the publication of its newest OASIS Standard, approved by the members on 30 August 2021:

LegalRuleML Core Specification Version 1.0
OASIS Standard
30 August 2021

Legal texts, e.g. legislation, regulations, contracts, and case law, are the source of norms, guidelines, and rules that govern societies. As text, it is difficult to label, exchange, and process content except by hand. In our current web-enabled world, where innovative e-government and e-commerce are increasingly the norm, providing machine-processable forms of legal content is crucial.

The objective of the LegalRuleML Core Specification Version 1.0 is to define a standard (expressed with XML-schema and Relax NG and on the basis of Consumer RuleML 1.02) that is able to represent the particularities of the legal normative rules with a rich, articulated, and meaningful mark-up language.

LegalRuleML models:

  • defeasibility of rules and defeasible logic;
  • deontic operators (e.g., obligations, permissions, prohibitions, rights);
  • semantic management of negation;
  • temporal management of rules and temporality in rules;
  • classification of norms (i.e., constitutive, prescriptive);
  • jurisdiction of norms;
  • isomorphism between rules and natural language normative provisions;
  • identification of parts of the norms (e.g. bearer, conditions);
  • authorial tracking of rules.

The project received 4 Statements of Use from Livio Robaldo, Swansea University, CSIRO Data61, and CirSFID-AlmaAI.


The OASIS Standard and all related files are available here:

HTML (Authotative):


Editable source:

XSD schemas:

RelaxNG schemas:

XSLT transformations:

XSD-conversion drivers:

RDFS metamodel:

Metamodel diagrams:


Distribution ZIP files

For your convenience, OASIS provides a complete package of the prose specification and related files in a ZIP distribution file. You can download the ZIP file here:

Our congratulations to the members of the OASIS LegalRuleML TC on achieving this milestone.