ISO/IEC 11179-32:2023

Information technology - Metadata registries (MDR) - Part 32: Metamodel for concept system registration

This document provides a specification for an extension to a metadata registry (MDR), as specified in ISO/IEC 11179-3:2023, in which metadata that describes concept systems can be registered. The specification in this document, together with the relevant clauses of the specification in ISO/IEC 11179-3, provides the ability to record the following metadata: concept systems and associated concepts; relations among concepts in a concept system; assertions about concepts in a concept system. The metamodel in this document is intended to support the full description of a concept system, including ontologies. Where there is a requirement to register an ontology where the details are defined elsewhere, consider using ISO/IEC 19763-3 instead.

Technologies de l'information — Registres de métadonnées (RM) — Partie 32: Métamodèle pour l'enregistrement de systèmes de concepts

General Information

• Status: Published
• Publication Date: 15-Jan-2023
• ICS: 35.040.50 - Automatic identification and data capture techniques
• Technical Committee: ISO/IEC JTC 1/SC 32 - Data management and interchange
• Drafting Committee: ISO/IEC JTC 1/SC 32/WG 2 - MetaData
• Current Stage: 6060 - International Standard published
• Start Date: 16-Jan-2023
• Due Date: 03-Jul-2023
• Completion Date: 16-Jan-2023

Overview

ISO/IEC 11179-32:2023 - "Information technology - Metadata registries (MDR) - Part 32: Metamodel for concept system registration" specifies an extension to the ISO/IEC 11179 metadata registry (MDR) model to register concept systems. The standard defines how to record concept systems and their components (concepts, relations, assertions and constraints) so registries can represent rich semantic structures - including ontologies - in a consistent, interoperable way. It complements ISO/IEC 11179-3:2023 and includes UML class diagrams, attribute tables and worked examples.

Key topics and requirements

• Metamodel specification: formal classes and associations to represent Concept_System, Relation, Relation_Role, Assertion, Constraint_Set and related elements.
• Binary relations: a dedicated package describing binary relation types and their properties.
• Assertions and constraints: mechanisms for recording statements about concepts and relationships, and for defining constraint sets.
• Conformance: degrees of conformance, conformance by feature, registry profiles and Implementation Conformance Statements (ICS) are defined to guide interoperable implementations.
• Documentation & models: use of UML class diagrams, textual specifications and package dependency diagrams to describe the metamodel.
• Examples & mappings: informative annexes provide mappings and examples (e.g., SKOS, OWL, ORM examples, car registration model) demonstrating how common semantic notations map to the metamodel.
• Interoperability guidance: relationship and mapping rules to ISO/IEC 11179-3 (classification schemes) and guidance to consider ISO/IEC 19763-3 when ontology details are defined externally.

Applications

ISO/IEC 11179-32 is intended for organizations and tools needing to register, publish or govern semantic artifacts:

• Metadata registries and catalogues - to record concept systems, taxonomies and thesauri alongside data element metadata.
• Data governance & semantic interoperability - to harmonize terminology and enforce consistent meaning across systems.
• Ontology and knowledge-graph tooling - to expose ontologies or conceptual models in an MDR-compliant registry (note: use ISO/IEC 19763-3 if ontology details are defined elsewhere).
• Standards bodies, registries, and data architects - to enable consistent registration, discovery and reuse of concepts, relations and assertions.

Related standards

• ISO/IEC 11179-3:2023 - core MDR metamodel that ISO/IEC 11179-32 extends.
• ISO/IEC 19763-3 - recommended when registering ontologies whose details live outside the MDR.
• Keywords: ISO/IEC 11179-32:2023, metadata registry (MDR), metamodel, concept system registration, ontologies, semantic interoperability, ISO metadata standards.

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 11179-32
First edition
2023-01
Information technology — Metadata
registries (MDR) —
Part 32:
Metamodel for concept system
registration
Technologies de l'information — Registres de métadonnées (RM) —
Partie 32: Métamodèle pour l'enregistrement de systèmes de concepts
Reference number
© ISO/IEC 2023
© ISO/IEC 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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© ISO/IEC 2023 – All rights reserved

Contents Page
Foreword .vii
Introduction .viii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 4
5 Conformance . 5
5.1 Overview of conformance . . 5
5.2 Degree of conformance . 5
5.2.1 General . 5
5.2.2 Strictly conforming implementations . 5
5.2.3 Conforming implementations . 6
5.3 Conformance by feature . 6
5.4 Registry conformance . . 6
5.4.1 Standard registry profiles . 6
5.4.2 Conformance labels . . 6
5.5 Implementation conformance statement (ICS) . 7
5.6 Obligation . 7
6 Relationship to ISO/IEC 11179-3 .7
6.1 Metamodel for a metadata registry . 7
6.2 Specification of the metamodel . 7
6.3 Use of UML Class diagrams and textual description . 8
6.4 Package dependencies . 8
6.5 Subclassing the Constraint_Set class . 9
6.6 Relationship to Classification region in ISO/IEC 11179-3:2023 . 9
7 Concept_System package . 9
7.1 Overview of the Concept_System package . 9
7.2 Concept System metamodel region . 9
7.2.1 Overview . 9
7.2.2 Classes in the Concept System metamodel region . 10
7.2.3 Associations of the Concept System metamodel region . 18
8 Binary_Relations package .21
8.1 Overview of Binary_Relations package . 21
8.2 Binary Relations metamodel region. 21
8.2.1 Overview . 21
8.2.2 Classes in the Binary Relations metamodel region . 21
8.2.3 Datatypes in the Binary_Relation metamodel region .22
Annex A (informative) Consolidated Class Hierarchy .24
Annex B (informative) Concept System Examples .25
Annex C (informative) Mapping ISO/IEC 11179-3:2023 Classification_Scheme to ISO/IEC
11179-32:2023 Concept_System .54
Bibliography .55
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List of Figures
Figure 1 — Package dependencies . 8
Figure 2 — Subclassing Constraint_Set. 9
Figure 3 — Concept system metamodel region .10
Figure 4 — Binary Relations metamodel region .21
Figure A.1 — Consolidated Class Hierarchy .24
Figure B.1 — Car Registration Model in ORM.30
Figure B.2 — Car Registration Ontology in OWL .39
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List of Tables
Table 1 — Attributes of Concept_System.12
Table 2 — Attributes of Relation .13
Table 3 — Attributes of Relation_Role .13
Table 4 — Attributes of Assertion.14
Table 5 — Attributes of Concept_Constraint_Set .16
Table 6 — Attributes of Relation_Constraint_Set .17
Table 7 — Examples of binary relations and their characterization .22
Table 8 — Attributes of Binary_Relation .22
Table 9 — Values of Reflexivity enumeration .22
Table 10 — Values of Symmetry enumeration .23
Table 11 — Values of Reflexivity enumeration .23
Table B.1 — Correspondences of ISO/IEC 11179-32 concept system metamodel to selected
notations .25
Table B.2 — SKOS-CORE as an ISO/IEC 11179-32 Concept System .26
Table B.3 — SKOS relations as ISO/IEC 11179-32 Binary Relations .26
Table B.4 — SKOS Thesaurus example — ISO/IEC 11179-32 Concept System .27
Table B.5 — SKOS Thesaurus Example — ISO/IEC 11179-32 Concepts .27
Table B.6 — SKOS Thesaurus Example — ISO/IEC 11179-32 Links .27
Table B.7 — SKOS Thesaurus Example — ISO/IEC 11179-31 Conceptual Domains .28
Table B.8 — SKOS Thesaurus Example — ISO/IEC 11179-31 Value Domains .28
Table B.9 — ORM as an ISO/IEC 11179-32 Concept System .29
Table B.10 — ORM Relations as ISO/IEC 11179-32 Binary Relations .29
Table B.11 — ORM Roles as ISO/IEC 11179-32 Relation Roles .29
Table B.12 — Car Registration Model in ORM — ISO/IEC 11179-32 Concept System .32
Table B.13 — Car Registration Model in ORM — ISO/IEC 11179-32 Concepts .32
Table B.14 — Car Registration Model in ORM — ISO/IEC 11179-32 Binary Relations .32
Table B.15 — Car Registration Model in ORM — ISO/IEC 11179-32 Links .33
Table B.16 — OWL constructs with directly corresponding ISO/IEC 11179-32 metamodel
elements .34
Table B.17 — OWL built-in constructs described in OWL metamodel .34
Table B.18 — OWL as an ISO/IEC 11179-32 Concept System .35
Table B.19 — OWL Concepts as ISO/IEC 11179-32 Concepts .35
Table B.20 — OWL Binary Relations as ISO/IEC 11179-32 Binary Relations.35
Table B.21 — OWL Relations (except Binary Relations) as ISO/IEC 11179-32 Relations .36
Table B.22 — OWL Constructs as ISO/IEC 11179-32 Relation Roles .36
Table B.23 — OWL Constructs as ISO/IEC 11179-32 Links.37
Table B.24 — Car Registration Model in OWL — ISO/IEC 11179-32 Concept System .43
Table B.25 — Car Registration Model in OWL — ISO/IEC 11179-32 Concepts .43
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Table B.26 — Car Registration Model in OWL — ISO/IEC 11179-32 Binary Relations .43
Table B.27 — Car Registration Model in OWL — ISO/IEC 11179-32 Relation Roles . 44
Table B.28 — Car Registration Model in OWL — ISO/IEC 11179-32 Links . 44
Table B.29 — Car Registration Model in OWL — ISO/IEC 11179-32 Assertions .48
Table B.30 — CL Metamodel – ISO/IEC 11179-32 Concept System .51
Table B.31 — CL Metamodel – ISO/IEC 11179-32 Binary Relations .51
Table B.32 — CLIF Units Example — ISO/IEC 11179-32 Concept System .51
Table B.33 — CLIF Units Example — ISO/IEC 11179-32 Concepts .52
Table B.34 — CLIF Units Example — ISO/IEC 11179-32 Binary Relations .52
Table B.35 — CLIF Units Example — ISO/IEC 11179-32 Relations Roles .52
Table B.36 — CLIF Units Example — ISO/IEC 11179-32 Links .52
Table B.37 — CLIF Units Example — ISO/IEC 11179-32 Assertions .53
Table C.1 — Summary view of the mapping of Classification_Scheme to Concept_System .54
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Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance
are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria
needed for the different types of document should be noted. This document was drafted in
accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC/JTC 1, Information technology,
Subcommittee SC 32, Data management and interchange.
A list of all parts in the ISO/IEC 11179 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national-committees.
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Introduction
ISO/IEC 11179-3 specifies the structure of a Metadata Registry (MDR) and provides a metamodel for
registry common facilities. That metamodel is intended to be extended by other parts of ISO/IEC 11179
for specific purposes.
This first edition of ISO/IEC 11179-32, is part of a restructuring of ISO/IEC 11179-3:2013, which has
now been broken into multiple parts. This document provides a metamodel for registering metadata
about concept systems and binary relations in a Metadata Registry (MDR), as extensions to the registry
metamodel specified in ISO/IEC 11179-3.
In Clauses 7 and 8, this document uses:
— bold font to highlight terms which represent metadata objects specified by the metamodel;
— normal text for terms which represent concepts defined in Clause 3.
EXAMPLE Concept (7.2.2.1) is a class each instance of which models a concept.
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© ISO/IEC 2023 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 11179-32:2023(E)
Information technology — Metadata registries (MDR) —
Part 32:
Metamodel for concept system registration
1 Scope
This document provides a specification for an extension to a metadata registry (MDR), as specified in
ISO/IEC 11179-3:2023, in which metadata that describes concept systems can be registered.
The specification in this document, together with the relevant clauses of the specification in
ISO/IEC 11179-3, provides the ability to record the following metadata:
— concept systems and associated concepts;
— relations among concepts in a concept system;
— assertions about concepts in a concept system.
The metamodel in this document is intended to support the full description of a concept system,
including ontologies.
Where there is a requirement to register an ontology where the details are defined elsewhere, consider
[8]
using ISO/IEC 19763-3 instead.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 11179-3:2023, Information technology — Metadata registries (MDR) — Part 3: Metamodel for
registry common facilities
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 11179-3 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
concept
unit of knowledge created by a unique combination of characteristics
Note 1 to entry: Concepts are not necessarily bound to particular natural languages. They are, however,
influenced by the social or cultural background which often leads to different categorizations.
Note 2 to entry: This is the concept “concept” as used and designated by the term “concept” in terminology work.
It is a very different concept from that designated by other domains such as industrial automation or marketing.
© ISO/IEC 2023 – All rights reserved

Note 3 to entry: A concept is independent of its representation.
[SOURCE: ISO 1087:2019, 3.2.7, modified — Reference to definition of characteristics removed. Note 3 to
entry added.]
3.2
concept system
system of concepts
set of concepts (3.1) structured in one or more related domains according to the concept relations (3.3)
among its concepts
[SOURCE: ISO 1087:2019, 3.2.28]
3.3
relation
concept relation
sense in which concepts (3.1) may be connected, via constituent relation roles (3.4)
EXAMPLE Causality is a relation with two constituent roles: cause and effect.
Note 1 to entry: The related concepts may be general or individual concepts.
3.4
relation role
role (3.5) that a concept (3.1) plays in a relation (3.3)
3.5
role
specified responsibilities
3.6
link
member of a relation (3.3)
3.7
link end
end of a link (3.6), identifying the relation role (3.4) played by a concept (3.1) in the link
3.8
binary relation
relation (3.3) with arity (3.9) equal to 2 (i.e. whose members all have two ends)
Note 1 to entry: Most common semantic relations are binary, e.g. “equals”, “less than”, “greater than”, “is part of”,
etc. An example of a relation which is not binary is “betweenness” (e.g. A is between B and C.).
3.9
arity
number of arguments that a function takes
3.10
reflexivity
characterization of a binary relation (3.8) as reflexive, irreflexive or antireflexive
Note 1 to entry: A binary relation, R, is reflexive if for all x, R(x,x) is true. Equality is an example of a reflexive
relation.
Note 2 to entry: A binary relation, R, is irreflexive if it is not reflexive. i.e., R(x,x) is not necessarily true for all x.
Note 3 to entry: A binary relation, R, is antireflexive if for all x, R(x,x) is false. Inequality is an example of
an antireflexive relation. An antireflexive relation is also irreflexive, but antireflexive is a more specific
characterization.
© ISO/IEC 2023 – All rights reserved

3.11
symmetry
characterization of a binary relation (3.8) as symmetric, asymmetric or antisymmetric
Note 1 to entry: A binary relation, R, is symmetric if for all x, y: R(x,y) implies R(y,x).
EXAMPLE 1 Symmetric relations include: “equals”, “not equals”, “within-2-miles-of”, etc.
Note 2 to entry: Symmetry does not imply reflexivity (3.18).
EXAMPLE 2 the “inequality” relation is symmetric, but antireflexive.
Note 3 to entry: A binary relation, R, is asymmetric if for all x,y: R(x,y) does not imply R(y,x).
EXAMPLE 3 Asymmetric relations include: “less than”, “likes”, “father of”, etc.
Note 4 to entry: A binary relation, R, is anti-symmetric if for all x,y: R(x,y) implies not R(y,x). An antisymmetric
relation is also asymmetric, but antisymmetric is a more specific characterization.
EXAMPLE 4 “less than” is an antisymmetric relation.
Note 5 to entry: An asymmetric relation is not necessarily antisymmetric.
EXAMPLE 5 Less than or equals.
3.12
transitivity
characterization of a binary relation (3.8) as: transitive, intransitive or antitransitive
Note 1 to entry: A binary relation, R, is transitive, if for all x,y,z: R(x,y) and R(y,z) implies R(x,z). Examples of
transitive relations include equality, less than and less than or equals.
Note 2 to entry: A binary relation, R, is intransitive if it is not transitive i.e. R(x,y) and R(y,z) does not imply R(x,z).
Note 3 to entry: A binary relation, R, is antitransitive if for all x,y,z: R(x,y) and R(y,z) implies not R(x,z).
Note 4 to entry: An antitransitive relation is also intransitive, but antitransitive is a more specific characterization.
3.13
object
anything perceivable or conceivable
Note 1 to entry: Objects can be material (e.g. “engine”, “sheet of paper”, “diamond”), immaterial (e.g. “conversion
ratio”, “project plan”) or imagined (e.g. “unicorn”, “scientific hypothesis”).
[SOURCE: ISO 1087:2019, 3.1.1]
3.14
property
feature of an object (3.13)
EXAMPLE 1 “Being made of wood” as a property of a given “table”.
EXAMPLE 2 “Belonging to person A” as a property of a given “pet”.
EXAMPLE 3 “Having been formulated by Einstein” as a property of the equation “E = mc ”.
EXAMPLE 4 “Being compassionate” as a property of a given “person”.
EXAMPLE 5 “Having a given cable” as a property of a given “computer mouse”.
Note 1 to entry: One or more objects can have the same property.
[SOURCE: ISO 1087:2019, 3.1.3]
© ISO/IEC 2023 – All rights reserved

3.15
characteristic
abstraction of a property (3.14)
EXAMPLE “Having a cable for connecting with a computer” as a characteristic of the concept “cord mouse”.
Note 1 to entry: Characteristics are used for describing concepts (3.6).
[SOURCE: ISO 1087:2019, 3.2.1]
3.16
notation
formal syntax and associated semantics for the representation of information
[5],[6],[7] [11] [12] [13] [9] [9] [17] [4]
EXAMPLE UML, MOF, OCL, OWL /RDF, SKOS, CGIF, XCL, XTM or ISO/IEC 11404
Note 1 to entry: A formal syntax consists of a set of symbols and the rules for their use.
Note 2 to entry: Formal syntax is often intended for machine processing.
[SOURCE: ISO/IEC 11179-3:2023, 3.2.36]
3.17
assertion
sentence or proposition in logic which is asserted (or assumed) to be true
3.18
cardinality
number of elements in a set
Note 1 to entry: cf. multiplicity (3.19)
[5]
Note 2 to entry: Adapted from ISO/IEC 19501:2005, Glossary.
3.19
multiplicity
specification of the range of allowable cardinalities (3.18) that a set may assume
Note 1 to entry: Multiplicity specifications may be given for roles within associations (ISO/IEC 11179-3:2023,
3.1.5)
Note 2 to entry: A multiplicity is a (possibly infinite) subset of the nonnegative integers
[5]
Note 3 to entry: Adapted from ISO/IEC 19501:2005, Glossary.
3.20
taxonomy
type of hierarchy which deals with generalization/specialization relationships
Note 1 to entry: cf. meronomy (3.21)
3.21
meronomy
type of hierarchy which deals with part-whole relationships
Note 1 to entry: cf. taxonomy (3.20)
4 Abbreviated terms
CD Conceptual Domain
[9]
CL Common Logic
© ISO/IEC 2023 – All rights reserved

[9]
CLIF Common Logic Interchange Format
[11]
OWL Web Ontology Language
OWL-DL OWL Description Logic
[12]
RDF Resource Description Framework
[13]
SKOS Simple Knowledge Organization System
[5][6][7]
UML Unified Modeling Language
URI Uniform Resource Identifier
[15]
W3C World Wide Web Consortium
[9]
XCL eXtended Common Logic markup language
[16]
XML eXtensible Markup Language
[17]
XTM XML Topic Maps
5 Conformance
5.1 Overview of conformance
Conformance rules for a Metadata Registry are specified in ISO/IEC 11179-3:2023, Clause 4. The clause
“Degree of Conformance” is repeated here for convenience. The subsequent subclauses extend the rules
from ISO/IEC 11179-3.
5.2 Degree of conformance
5.2.1 General
The distinction between “strictly conforming” and “conforming” implementations is necessary
to address the simultaneous needs for interoperability and extensions. This document describes
specifications that promote interoperability. Extensions are motivated by needs of users, vendors,
institutions and industries, and:
a) are not directly specified by this document;
b) are specified and agreed to outside this document;
c) may serve as trial usage for future editions of this document.
A strictly conforming implementation can be limited in usefulness but is maximally interoperable with
respect to this document. A conforming implementation can be more useful but can be less interoperable
with respect to this document.
5.2.2 Strictly conforming implementations
A strictly conforming implementation:
a) shall support all mandatory, optional and conditional classes, attributes, datatypes and
associations;
b) shall not use, test, access or probe for any extension features nor extensions to classes, attributes,
datatypes, associations or any combination thereof;
c) shall not recognize, nor act on, nor allow the production of classes, attributes, datatypes,
associations or any combination thereof that are dependent on any unspecified, undefined or
implementation-defined behaviour.
NOTE The use of extensions to the metamodel can cause undefined behaviour.
© ISO/IEC 2023 – All rights reserved

5.2.3 Conforming implementations
A conforming implementation:
a) shall support all mandatory, optional and conditional classes, attributes, datatypes and
associations;
b) as permitted by the implementation, may use, test, access or probe for extension features or
extensions to classes, attributes, datatypes, associations or any combination thereof;
c) may recognize, act on or allow the production of classes, attributes, datatypes, associations or any
combination thereof that are dependent on implementation-defined behaviour.
NOTE 1 All strictly conforming implementations are also conforming implementations.
NOTE 2 The use of extensions to the metamodel can cause undefined behaviour.
5.3 Conformance by feature
Conformance claims may be made to Clause 7 and optionally Clause 8, or to specific features within
these clauses. Those clauses are also dependent upon one or more other clauses of ISO/IEC 11179-3, so
conformance to all or part of those clauses shall be understood to imply conformance also to relevant
provisions specified in one or more of the clauses in ISO/IEC 11179-3.
A conformance statement shall specify exactly the features supported and not supported.
5.4 Registry conformance
5.4.1 Standard registry profiles
This document specifies the following standard profiles in addition to those specified in
ISO/IEC 11179-3:2023, 4.4.2.
— Concept System Registry: Implements Clause 7 in addition to all provisions of the “Basic Registry”
profile of ISO/IEC 11179-3:2023, 4.4.2;
— Concept System and Binary Relations Registry: Implements Clauses 7 and 8 in addition to all
provisions of the “Basic Registry” profile of ISO/IEC 11179-3:2023, 4.4.2;
— Concept System Registry with mapping: Implements Clause 7 in addition to all provisions of the
“Basic Registry with mapping” profile of ISO/IEC 11179-3:2023, 4.4.2;
— Concept System and Binary Relations Registry with mapping: Implements Clauses 7 and 8 in
addition to all provisions of the “Basic Registry with mapping” profile of ISO/IEC 11179-3:2023,
4.4.2.
5.4.2 Conformance labels
Conformance to the profiles specified in 5.4.1 may be claimed using the following labels, respectively:
— ISO/IEC 11179-32:2023 Concept System Registry;
— ISO/IEC 11179-32:2023 Concept System and Binary Relations Registry;
— ISO/IEC 11179-32:2023 Concept System Registry with mapping;
— ISO/IEC 11179-32:2023 Concept System Registry and Binary Relations with mapping.
© ISO/IEC 2023 – All rights reserved

5.5 Implementation conformance statement (ICS)
An implementation claiming conformance to this document shall include an Implementation
Conformance Statement stating:
a) whether it conforms or strictly conforms;
b) which clauses are or are not supported;
c) what extensions, if any, are supported or used.
A standard profile may be referenced, if applicable.
EXAMPLE Product Z strictly conforms to ISO/IEC 11179-32:2023 Concept System Registry with Mapping.
5.6 Obligation
Properties and relationships specified in this document are one of: Mandatory, Conditional or Optional.
The obligation is not explicitly stated but is to be inferred from the multiplicity of the property or
relationship, and the presence or absence of a condition. In addition, a Registration Authority can specify
additional constraints to be applied to particular Administered_Items (see ISO/IEC 11179-3:2023,
9.4.2), using Constraint_Sets (see ISO/IEC 11179-3:2023, 9.4.6). See 6.5.
For the purpose of conformance:
a) Mandatory properties and relationships shall exist and shall conform to the provisions of this
document.
b) Anything specified as Conditional within this document shall be treated as Mandatory if the
associated condition is satisfied and shall otherwise be not present.
c) Optional properties and relationships are not required to exist, but if they do exist, they shall
conform to the provisions of this document.
Such obligation is enforced if and only if the Registration Status of the associated registry items is
[3]
Recorded or higher (see ISO/IEC 11179-3:2023, 9.4.6.3 and ISO/IEC 11179-6:2023, 4.4).
6 Relationship to ISO/IEC 11179-3
6.1 Metamodel for a metadata registry
A metamodel is a model that describes other models. A metamodel provides a mechanism for
understanding the precise structure and components of the specified models, which are needed for the
successful sharing of the models by users, software facilities or both.
ISO/IEC 11179-3 uses a metamodel to describe the information model of a metadata registry. The
registry in turn will be used to describe and model other data, for example about enterprise, public
administration or business applications. The registry metamodel is specified as a conceptual data
model, i.e., one that describes how relevant information is structured in the natural world. In other
words, it is how the human mind is accustomed to thinking of the information.
6.2 Specification of the metamodel
The conventions used in specifying the metamodel are described in ISO/IEC 11179-3:2023, 5.3. Many
of the classes specified in this document inherit from Item, which is specified in ISO/IEC 11179-3:2023,
6.4.2.1. As Items, instances of these classes may be identified, registered, administered, named, defined
and classified.
© ISO/IEC 2023 – All rights reserved

6.3 Use of UML Class diagrams and textual description
This document uses both text and UML class diagrams to describe the metamodel. Both are normative
and are intended to be complementary. However, if a conflict exists between what is specified in
UML and what is specified in text, the text takes precedence until a correction is made to make them
consistent. Further, if a conflict exists between a formal definition and other normative text, the formal
definition takes precedence until a correction is made to make them consistent.
A consolidated UML class hierarchy is included as Annex A.
While the model diagrams are presented in UML notation, this document does not assume nor endorse
any specific system environment, database management system, database design paradigm, system
development methodology, data definition language, command language, system interface, user
interface, computing platform or any technology required for implementation.
6.4 Package dependencies
Figure 1 — Package dependencies
Figure 1 illustrates the dependencies among the packages. The Concept_System and Binary_Relations
packages are specified in this document. All the other packages are specified in ISO/IEC 11179-3:2023.
The lines in the figure illustrate dependencies in the direction of the arrow. In order to implement a
package that has dependencies, the packages on which it is dependent shall also be implemented. The
dependencies are of three types:
a) Subclassing from classes in another package, e.g. Relation (7.2.2.3) in the Concept_System package
is subclassed from the Concept class in the Basic and Core package (ISO/IEC 11179-3:2023,
6.4.2.2), and Concept_Constraint_Set (7.2.2.8) in the Concept_System package is subclassed from
the Constraint_Set class in the Registration package (ISO/IEC 11179-3:2023, 9.4.6).
b) Relationship between classes, e.g. Registered_Item in the Registration package
(ISO/IEC 11179-3:2023, 9.4.1) has a relationship with Reference_Document in the Basic_and_
Core package (ISO/IEC 11179-3:2023, 6.3.8).
© ISO/IEC 2023 – All rights reserved

c) Some attributes use a predefined datatype or a class from another package as a datatype,
e.g. the contact attribute of the Stewardship_Record class in the Registration package
(ISO/IEC 11179-3:2023, 9.4.7) uses the Contact class of the Basic_and_Core package
(ISO/IEC 11179-3:2023, 6.3.5) as a datatype.
Conformance options are specified in Clause 5 and standard conformance profiles in 5.3.
6.5 Subclassing the Constraint_Set class
This document extends the Constraint_Set class (ISO/IEC 11179-3:2023, 9.4.6) by specifying subclasses
to support constraints specified in this document. See Figure 2.
Figure 2 — Subclassing Constraint_Set
Concept_Constraint_Set is specified in 7.2.2.8.
Relation_Constraint_Set is specified in 7.2.2.9.
Any registry implementation shall provide a mechanism to enforce these constraints.
6.6 Relationship to Classification region in ISO/IEC 11179-3:2023
There are some overlaps in functionality between the Concept_System package specified in this
document and the Classification package specified in ISO/IEC 11179-3:2023, Clause 10. Annex C
provides a mapping between the two facilities and an explanation for the duplication.
7 Concept_System package
7.1 Overview of the Concept_System package
The Concept_System package consists of a single metamodel region, the Concept System metamodel
region.
7.2 Concept System metamodel region
7.2.1 Overview
The Concept System metamodel region is illustrated in Figure 3. The purpose of this metamodel region
is to describe concepts (abstract units of knowledge), represented by instances of Concept (7.2.2.1), and
the various relations, represented by instances of Relation (7.2.2.3), which hold among the concepts.
Support for more advanced concept systems, such as ontologies with formal semantics is provided
through the use of assertions, represented by instances of Assertion (7.2.2.5). Annex B provides
examples using SKOS, ORM, OWL and CLIF.
© ISO/IEC 2023 – All rights reserved

Figure 3 — Concept system metamodel region
7.2.2 Classes in the Concept System metamodel region
7.2.2.1 Concept class
7.2.2.1.1 Direct superclass
Concept is a subclass of Item (ISO/IEC 11179-3:2023, 6.4.2.1), allowing instances to be identified,
registered, administered, named, defined and classified.
7.2.2.1.2 Description of Concept
Concept is part of the Core metamodel and is specified in ISO/IEC 11179-3:2023, 6.4.2.2. Additional
associations are specified in this metamodel region.
Concept is a class, each instance of which models a concept, a unit of knowledge created by a unique
combination of characteristics. A concept is independent of representation.
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Concept is a superclass of both Relation (7.2.2.3) and Relation_Role (7.2.2.4). These specializations
are disjoint, and the specialization hierarchy is incomplete.
7.2.2.1.3 Associations of Concept
As a subclass of Item, Concept inherits Item’s associations (ISO/IEC 11179-3:2023, 6.4.2.1.2). This
metamodel region specifies the following associations:
— concept_system_membership (7.2.3.1);
— concept_source (7.2.3.2);
— assertion_about_concept (7.2.3.7);
— link_end_concept (7.2.3.11).
7.2.2.1.4 Attributes of Concept
The attributes of Concept are specified in ISO/IEC 11179-3:2023, 6.4.2.2.4.
7.2.2.2 Concept_System class
7.2.2.2.1 Direct superclass
Concept_System is a subclass of Item (ISO/IEC 11179-3:2023, 6.4.2.1), allowing instances to be
identified, registered, administered, named, defined and classified.
7.2.2.2.2 Description of Concept_System
Concept_System is a class, each instance of which models a concept system, a set of concepts structured
according to the relations among them.
A minimal concept system can simply be a collection of concepts. A more elaborate concept system
could be a collection of concepts organized into a taxonomy or meronomy specified by means of various
relations (e.g. semantic relations) among the concepts.
NOTE 1 Examples of concept systems are included in Annex B.
NOTE 2 If a concept system is available in multiple notations, it is good practice to register the concept system
only once and to use reference documents to record the various notations.
7.2.2.2.3 Associations of Concept_System
A Concept_System has the following associations:
— concept_system_membership (7.2.3.1);
— concept_source (7.2.3.2);
— concept_system_reference (7.2.3.3);
— concept_system_importation (7.2.3.4);
— assertion_inclusion (7.2.3.6).
7.2.2.2.4 Attributes of Concept_System
See Table 1.
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Table 1 — Attributes of Concept_System
Attribute name Multiplicity Datatype Description
notat
...