Blockchain and distributed ledger technologies — Identifiers of subjects and objects for the design of blockchain systems

This document provides an overview of identifiers [and their standards and register(s)] relevant for the design of blockchain systems and the interoperability of those systems with non-blockchain systems. The following criteria were used for inclusion of identifiers in this document: — Identifiers (and their standards and registers) issued by the public sector for subjects and objects such as citizen numbers, business registration numbers or land registration numbers; — Identifiers that are internationally recognized and fulfil one of the following criteria: — An identifier is an international standard of an SDO (Standard Development Organization); — An identifier is a de facto standard according to the norms of the industry involved (even if it is not an international standard of an SDO). — Identifiers that have relevance for DLT systems as it fulfils one of the following criteria: — An identifier that has been used without DLT, but has proven to solve the problems of DLT services using DLT; — An identifier that was designed with the usage of DLT in mind from the beginning.

Technologies des chaînes de blocs et technologies de registre distribué — Identifiants des sujets et des objets pour la conception des systèmes de chaînes de blocs

General Information

Status
Published
Publication Date
04-Jun-2023
Current Stage
6060 - International Standard published
Start Date
05-Jun-2023
Due Date
21-Oct-2023
Completion Date
05-Jun-2023
Ref Project

Buy Standard

Technical report
ISO/TR 6039:2023 - Blockchain and distributed ledger technologies — Identifiers of subjects and objects for the design of blockchain systems Released:5. 06. 2023
English language
50 pages
sale 15% off
Preview
sale 15% off
Preview
Draft
REDLINE ISO/PRF TR 6039 - Blockchain and distributed ledger technologies — Identifiers of subjects and objects for the design of blockchain systems Released:9. 05. 2023
English language
49 pages
sale 15% off
Preview
sale 15% off
Preview
Draft
ISO/PRF TR 6039 - Blockchain and distributed ledger technologies — Identifiers of subjects and objects for the design of blockchain systems Released:9. 05. 2023
English language
49 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

TECHNICAL ISO/TR
REPORT 6039
First edition
2023-06
Blockchain and distributed ledger
technologies — Identifiers of
subjects and objects for the design of
blockchain systems
Technologies des chaînes de blocs et technologies de registre
distribué — Identifiants des sujets et des objets pour la conception des
systèmes de chaînes de blocs
Reference number
ISO/TR 6039:2023(E)
© ISO 2023

---------------------- Page: 1 ----------------------
ISO/TR 6039:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2023 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/TR 6039:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Considerations for the design of blockchain systems . 2
4.1 General . 2
4.2 Reference Architecture . 3
4.3 Decentralized Identifiers . 4
5  Identifiers of subjects . 5
5.1 General . 5
5.2 Identifiers of natural persons . 5
5.2.1 Public sector identifiers . 5
5.2.2 Private sector identifiers . 6
5.3 Identifiers of legal entities . 6
5.3.1 Public sector identifiers . 6
5.3.2 Private sector identifiers . 8
6  Identifiers of objects .9
6.1 Introduction . 9
6.2 Identifiers of objects used in multiple industries (“horizontals”) . 10
6.2.1 Supply chain. 10
6.2.2 Telecom .13
6.2.3 Internet . 15
6.2.4 Patents and trade marks . 16
6.2.5 Postal services . 16
6.3 Identifiers of objects used in specific industries (“verticals”) . 16
6.3.1 Logistics industry . . 16
6.3.2 Agricultural and food industry . 20
6.3.3 Financial industry . 26
6.3.4 Healthcare industry .28
6.3.5 Media industry .29
6.3.6 Electronic devices industry . 31
6.3.7 Automotive industry . 32
6.3.8 Mining industry .34
6.3.9 Chemical industry .34
6.3.10 Land administration and real estate . 35
Annex A (informative)  Identifier standards as issued by government agencies and SDOs .36
Annex B (informative)  Identifier categories .37
Annex C (informative)  List of agricultural vocabularies published by ISO .38
Bibliography .41
iii
© ISO 2023 – All rights reserved

---------------------- Page: 3 ----------------------
ISO/TR 6039:2023(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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 ISO 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).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
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.
This document was prepared by Technical Committee ISO/TC 307, Blockchain and distributed ledger
technologies.
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.
iv
  © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/TR 6039:2023(E)
Introduction
This document, which is on the available standards and registers of identifiers of subjects and objects
issued by government agencies and standard development organizations (SDOs) (see Annex A), is
intended to support designers with the innovation process for their development of (international)
blockchain systems for multiple purposes. It also supports the interoperability of those systems
with non-blockchain systems because identifiers are mission critical building blocks of information
technology systems including the blockchain systems.
Identifiers can identify “subjects” (with rights and obligations) or “objects” (without rights and
obligations). This distinction is relevant in legal systems of any country in case at least two subjects of
the same or of multiple countries are involved.
[1]
Subclause 4.3 addresses decentralized identifiers that leverage blockchain (see W3C ). This document
is not a report on those “decentralized identifiers” standards and registers.
This document is intended to support designers of blockchain and other systems.
Identifiers issued by the public sector and used in information technology systems are mostly products
of a national history (including national legislation) and were mostly not designed for a computer age.
This historical legacy hinders the development of global standards and registers on the identification of
subjects and objects.
v
© ISO 2023 – All rights reserved

---------------------- Page: 5 ----------------------
TECHNICAL REPORT ISO/TR 6039:2023(E)
Blockchain and distributed ledger technologies —
Identifiers of subjects and objects for the design of
blockchain systems
1 Scope
This document provides an overview of identifiers [and their standards and register(s)] relevant for the
design of blockchain systems and the interoperability of those systems with non-blockchain systems.
The following criteria were used for inclusion of identifiers in this document:
— Identifiers (and their standards and registers) issued by the public sector for subjects and objects
such as citizen numbers, business registration numbers or land registration numbers;
— Identifiers that are internationally recognized and fulfil one of the following criteria:
— An identifier is an international standard of an SDO (Standard Development Organization);
— An identifier is a de facto standard according to the norms of the industry involved (even if it is
not an international standard of an SDO).
— Identifiers that have relevance for DLT systems as it fulfils one of the following criteria:
— An identifier that has been used without DLT, but has proven to solve the problems of DLT
services using DLT;
— An identifier that was designed with the usage of DLT in mind from the beginning.
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 22739, Blockchain and distributed ledger technologies — Vocabulary
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 22739 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
attribute
characteristic or property of an entity
[SOURCE: ISO/IEC 24760-1:2019, 3.1.3, modified — Example deleted.]
1
© ISO 2023 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/TR 6039:2023(E)
3.2
credential
set of data presented as evidence of a claimed or asserted identity and/or entitlements
[SOURCE: ISO/IEC 29115:2013, 3.8, modified — Note to entry deleted.]
3.3
decentralized identifier
DID
globally unique persistent identifier that does not require a centralized registration authority and is
often generated and/or registered cryptographically
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.4
decentralized identifier subject
DID subject
entity identified by a DID and described by a DID document
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.5
entity
item inside or outside an information and communication technology system such as a person,
organization, a device, a subsystem, or a group that has recognizable distinct existence
3.6
identifier
attribute or set of attributes that uniquely characterizes an identity in a domain
Note 1 to entry: An identifier can be a specifically created attribute with a value assigned to be unique within the
domain.
[SOURCE: ISO/IEC 24760-1:2019, 3.1.4, modified — Note to entry deleted.]
3.7
object
entity without rights and obligations
3.8
subject
entity with rights and obligations
3.9
verifiable credential
tamper-evident credential that has authorship that can be cryptographically verified
[SOURCE: W3C Verifiable Credentials Data Model v1.1]
4  Considerations for the design of blockchain systems
4.1 General
Designers of a blockchain system make choices for the design of their application such as:
— Which subjects will be included in the DLT service?
— Are the subjects only from one country (such as healthcare insurance) or from multiple countries
(such as for the international supply chain)?
2
  © ISO 2023 – All rights reserved

---------------------- Page: 7 ----------------------
ISO/TR 6039:2023(E)
— Are the identifiers of subjects of the public sector mandatory for the DLT service or are other options
possible (central or decentralized identifiers)?
— Which objects are planned to be included in the DLT service?
— Are the preferred identifiers standards available?
— Are the identifier data registers available and accessible?
— Do the available identifiers and attributes have the required data quality for the DLT service?
— Is the DLT system and its identifiers intended to be used with two (or more) DLT systems and/or
with non-DLT systems and/or should interoperability of the two or more systems or applications be
ensured to exchange information (data)?
An overview of subjects (natural persons and legal entities) and an overview of objects such as products,
assets, locations, documents, legal rights, and messages are included in this document. Objects are
owned by one or more subjects. In this document the object identifiers are distinguished in object
identifiers of “horizontal industries” (used by any industry) and object identifiers used by “vertical
industries” (used by a specific industry). Annex B provides an overview of identifier categories.
4.2  Reference Architecture
[6]
As specified in ISO 23257, DLT data can be classified according to its source as shown in Figure 1.
Figure 1 — Data categories from DLT stakeholder role perspective
[6]
The data sources identified here align with the six DLT roles identified in ISO 23257 as DLT subjects:
administrators, users, providers, developers, governors and auditors. Among these, administrators,
users and providers are typically the most relevant roles to use case definition. Stakeholders achieve
their aims by means of role-based interactions with the DLT system: A specific example could be the
data flows of subjects involved in the international supply chain: the exporter and its bank, the customs
of the exporter, the freight forwarders, the customs of the importer, the importer and its bank, all those
subjects need high quality identifiers of their business partners (and so the customs) involved and of
the goods that are shipped.
3
© ISO 2023 – All rights reserved

---------------------- Page: 8 ----------------------
ISO/TR 6039:2023(E)
SOURCE: ISO/TR 3242:2022, Figure 4
Figure 2 — Off-chain/on-chain data flow model
The identifier data (and relevant attributes) of subjects and objects are the data connectors to ensure an
efficient end-to-end digital process, mostly via multiple digital ecosystems of the market participants
involved. The passing of reference identifiers in the dataflow across on-chain and off-chain systems
contributes to the immutable, enhanced trust environment of a DLT system.
Interoperability requires high quality and accurate data (including of identifiers) that are key to
correctly recording and tracking the data-related operations of stakeholders to avoid operational risks.
[7] [8]
There are many definitions of data quality. ISO 8000-8 and ISO/IEC 25012 are excellent references
for designers to review the data quality of the identifiers that they will include in their design.
4.3  Decentralized Identifiers
Designers could consider the use of decentralized identifiers for their DLT systems. In response to
regulatory differences in relation to data privacy (for natural persons identifiers, attributes and data)
and governance across global trade ecosystem, two concepts have emerged to address compliance: self-
sovereign identity management and decentralized identifiers.
Decentralized identifier is an old and established concept. Examples include using a public key or a
[10]
transformation of it as an identifier and using Universally Unique Identifier. Many addresses used in
blockchain systems, such as for cryptocurrencies fall into this category.
[1]
W3C has published a framework [Decentralized Identifiers (DIDs) of 19 July 2022] acknowledging
a need in some circumstances for a globally unique identifier that is “self-sovereign”, that is, one that
does not depend on any issuing authority and defining Decentralized identifiers (DIDs) as a new kind of
identifier that enables verifiable, decentralized identity.
For the design process, a clear view of which subjects and objects is relevant to consider in the DLT
system and if all market participants involved will be committed to use a DLT system with decentralized
identifiers. The designers need also to understand if the DLT system is a stand-alone system or needs to
interact with other DLT systems and/or with non-DLT systems of one or more market participants. See
Figure 2 where interoperating DLT and non-DLT systems can be usefully modelled.
Decentralized identifiers are often used in a verifiable credential and are associated with subjects such
that the verifiable credential can be easily ported from the repository to another without the need to
reissue the credential. W3C has defined that anything can be a DID subject: person, group, organization,
physical thing, digital thing, logical thing, etc.”
4
  © ISO 2023 – All rights reserved

---------------------- Page: 9 ----------------------
ISO/TR 6039:2023(E)
The verification of “identifiers (and their attributes)” contained in verifiable credentials with the
registers involved is mission critical to ensure the identification of subjects and objects.
This document does not have verifiable credentials in its scope but it lists categories of identifiers and
attributes that can be contained as claims in verifiable credentials.
5  Identifiers of subjects
5.1 General
[12]
The United Nations members are sovereign states. Countries stipulate in their legislation how
identifiers for their citizens and legal entities are issued and who is allowed to use those identifiers
for which public or private purpose. The government agencies involved that issue the identifiers are
regarded the authoritative source of the identifiers and their attributes.
Subjects are entities with rights and obligations according to the legislation of the country involved.
There are two categories of subjects in countries: natural persons and legal entities for which
government agencies issue unique identifiers.
Governments agencies use their (unique) identifiers (and attributes) for the communication with their
citizens for their services and for e-government services inclusive for their social benefits programs.
For communication with legal entities, government agencies use the identifier (and attributes) issued
by the business register of their jurisdiction. Government agencies sometimes use additional identifiers
for specific functions such as tax numbers, VAT numbers, etc. Government identifiers are in general an
integral part of the authentication process for citizens and legal entities to get access to e-government
services.
Businesses have their own onboarding process for their customers, suppliers and partners and use
a CRM (Customer Relationship Management) system with identifiers. The identifier is used for many
business processes such as the invoicing process, reconciliation of payments data, access to helpdesks,
loyalty schemes and the authentication of the customers, suppliers and partners to specific e-commerce
or e-service of the business involved. In several industries, an industry identifier is used for joint
business processes often based on a rulebook, master agreement and/or a common platform.
This clause gives an overview of public and private identifiers (and attributes) designers could consider
to use for their CRM systems and applications
5.2  Identifiers of natural persons
5.2.1  Public sector identifiers
5.2.1.1 National identity number
The United Nations mention that the civil registration systems for the citizens of a jurisdiction have
three basic functions:
1) A legal and administrative function;
2) A statistical function;
3) The identity management function.
The identity management function assumes that civil registration provides accurate input into an
identity management systems or population register. The identity management system also services a
legal and identity function. The legal and administrative function of the provision of credentials enable
individuals to prove their identity.
The United Nations stresses that “Everyone has the right to be recognized as a person before the law, as
[13]
enshrined in Article 6 of the Universal Declaration on Human Rights” .
5
© ISO 2023 – All rights reserved

---------------------- Page: 10 ----------------------
ISO/TR 6039:2023(E)
The national identification number is used by government agencies as a means of tracking their citizens,
permanent residents and temporary residents for the purpose of work, taxations, government benefits,
education, healthcare and other official functions. The issuing of the identification number is stipulated
by the legislation of the country involved. Each country has its own standard for the identifier (and
attributes) of the citizen record. The access to registers with citizens data is limited by the laws of
the country involved. The UN published guidelines on the legislative framework for civil registrations.
[14]
The UN publishes no overview of “national identification numbers”. See Reference [15] for more
information on national identification numbers.
The OECD provides an overview of “tax identification numbers” (TIN) of many of the UN member
countries, or the functional equivalent for their citizens with the rules of the country involved in
relation to the issuance, structure, use and validity of its TIN. See Reference [16] for more information.
The authentication schemes of/for government agencies include directly or indirectly the citizen
number issued by the government involved.
5.2.1.2 Passport
The ICAO (International Civil Aviation Organization) issues the specifications for machine readable
passports. A passport is a travel document (so an object) issued by a government, primarily for the
[17]
purpose of travel, to certify the personal identity and nationality of its holder. The ICAO specifications
include mandatory data elements such as:
— the issuing state or organization (in code);
— the passport number must uniquely identify the document from all other machine readable
documents issued by the state;
— a primary and a secondary identifier as defined by the state.
[18]
ISO/IEC 7501-1 defines machine readable passports.
5.2.2  Private sector identifiers
Businesses and NGOs design(ed) their own identifier (and attributes) for the registration of their
natural person customers or members. These identifiers can include industry standards (such as part
of the credit card number). Businesses (such as organizations in the financial industry) must also
often include an identifier issued by a public sector agency of the country involved in the files of their
customers. These identifiers mostly can only be used for specific purposes allowed or prescribed by the
legislation of the country involved.
5.2.2.1  ISO 24366 Financial services — Natural Person Identifier (NPI)
[19]
ISO 24366 specifies a machine-readable, unambiguous natural person identifier (NPI) and the
relevant reference data to uniquely identify the natural person relevant to any financial transaction
rather than the personal identifying information.
5.3  Identifiers of legal entities
5.3.1  Public sector identifiers
5.3.1.1  Identifiers of legal entities registered in business registers
All countries have legal entities (with rights and obligations) of several legal forms (see 5.3.2.1) that are
in general registered with an identifier in a business register or other public register of that country.
Not all countries have a complete register of all legal entities of all their legal forms. All business
registers have their own (national) identifier standard for legal entities and do not use a standard of an
international SDO (Standard Development Organization). All business registers have their own rules on
the access to the data of legal entities and if a fee is required to get access to (part of) the data.
6
  © ISO 2023 – All rights reserved

---------------------- Page: 11 ----------------------
ISO/TR 6039:2023(E)
The G20-FSB mandated the Global Legal Entity Identifier Foundation (GLEIF) to take care of the
[20]
“Registration Authorities List”, which includes over 770 business registers, and other relevant
registers of which the data are available free of charge for any user. The register of the Registration
Authorities is available.
[16]
The OECD makes an overview available to many UN member countries of their “tax identification
numbers” (TIN) for legal entities or their functional equivalents with the rules of the country involved
in relation to the issuance, structure, use and validity of its TIN.
5.3.1.2  ISO 20275 Financial services — Entity legal forms (ELF)
[21]
ISO 20275 specifies the elements of an unambiguous scheme to identify the distinct entity legal
forms in
...

Style Definition
...
Style Definition
...
Style Definition
1 ISO /PRF TR 6039:2021(X) .
Style Definition
...
2 ISO /TC 307/WG 6
Style Definition
...
Style Definition
3 Secretariat: SA .
Style Definition
...
4 1-1605-08
Date: 2023-0
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
5 Blockchain and distributed ledger technologies — Identifiers of
...
Style Definition
6 subjects and objects for the design of blockchain systems
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
7
Style Definition
...
Style Definition
...
Style Definition
...
8 WDTechnologies des chaînes de blocs et technologies de registre distribué — Identifiants des
Style Definition
...
9 sujets et des objets pour la conception des systèmes de chaînes de blocs
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
10 FDIS stage Style Definition
...
Style Definition
...
11
Style Definition
...
Style Definition
...
12 Warning for WDs and CDs
Style Definition
...
13 This document is not an ISO International Standard. It is distributed for review and comment. It is subject to
Style Definition
...
14 change without notice and may not be referred to as an International Standard.
Style Definition
...
15 Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of
Style Definition
...
16 which they are aware and to provide supporting documentation.
Style Definition
...
17 Style Definition
...
Style Definition
18 .
Style Definition
19 .
Style Definition
...
Style Definition
...
© ISO 2021 – All rights reserved Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Style Definition
...
Formatted
...
Formatted
...
Formatted
...
Formatted
...
Formatted
...
Formatted

---------------------- Page: 1 ----------------------
ISO #####-#:####(X)
© ISO 2021
2 © ISO #### – All rights reserved

---------------------- Page: 2 ----------------------
Standard  ISO/PRF TR 6039:2021(X2023(E)
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
© ISO 2023
Formatted: Left, Space After: 0 pt, Line spacing: single
Formatted: Left: 1.9 cm, Right: 1.9 cm, Bottom: 1 cm,
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, Gutter: 0 cm, Header distance from edge: 1.27 cm,
including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can Footer distance from edge: 0.5 cm, Numbering: Restart
be requested from either ISO at the address below or ISO’s member body in the country of the requester. each page
Formatted: Indent: Left: 0 cm, Right: 0 cm, Adjust
ISO copyright office
space between Latin and Asian text, Adjust space
CP 401 • Ch. de Blandonnet 8
between Asian text and numbers
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Formatted: French (France)
EmailE-mail: copyright@iso.org
Formatted: French (France)
Website: www.iso.orgwww.iso.org
Formatted: French (France)
Published in Switzerland
Formatted: English (United Kingdom)
Formatted: English (United Kingdom)
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Space After: 0 pt, Line spacing: single
© ISO 20212023 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO /PRF TR 6039:2021(X2023(E)
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Contents
Formatted: Space After: 0 pt, Line spacing: single
Foreword . Error! Bookmark not defined.
Introduction. Error! Bookmark not defined.
1 Scope . Error! Bookmark not defined.
2 Normative references . Error! Bookmark not defined.
3 Terms and definitions . Error! Bookmark not defined.
4 Considerations for the design of blockchain systems . Error! Bookmark not defined.
4.1 General . Error! Bookmark not defined.
4.2 Reference Architecture . Error! Bookmark not defined.
4.3 Decentralized Identifiers . Error! Bookmark not defined.
5 Identifiers of subjects . Error! Bookmark not defined.
5.1 General . Error! Bookmark not defined.
5.2 Identifiers of natural persons . Error! Bookmark not defined.
5.3 Identifiers of legal entities . Error! Bookmark not defined.
6 Identifiers of objects . Error! Bookmark not defined.
6.1 Introduction . Error! Bookmark not defined.
6.2 Identifiers of objects used in multiple industries (“horizontals”)Error! Bookmark not defined.
6.3 Identifiers of objects used in specific industries (“verticals”) . Error! Bookmark not defined.
(informative) Identifier standards as issued by government agencies and SDOsError! Bookmark
not defined.
(informative) Identifier categories . Error! Bookmark not defined.
(informative) List of agricultural vocabularies published by ISO . Error! Bookmark not defined.
Bibliography . Error! Bookmark not defined.

Foreword iv
Introduction v
1 Scope 1
2 Normative references 1
3 Terms and definitions 1
4 Considerations for the design of blockchain systems 2
4.1 Introduction 2
4.2 Reference Architecture 3
4.3 Decentralised Identifiers 4
5 Identifiers of subjects 4
5.1 Introduction 4
5.2 Identifiers of natural persons 5
5.2.1 Public sector identifiers 5
Formatted: Font: 11 pt
5.2.2 Private sector identifiers 6
Formatted: Font: 11 pt
5.3 Identifiers of legal entities 6
Formatted: Space After: 0 pt, Line spacing: single
iv © ISO 2021 2023 – All rights reserved

---------------------- Page: 4 ----------------------
Standard  ISO/PRF TR 6039:2021(X2023(E)
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
5.3.1 Public sector identifiers 6
Formatted: Left, Space After: 0 pt, Line spacing: single
5.3.2 Private sector identifiers 8
6 Identifiers of objects 9
6.1 Introduction 9
6.2 Identifiers of objects used in multiple industries (“horizontals”) 9
6.2.1 Supply chain 9
6.2.2 Telecom 12
6.2.3 Internet 14
6.2.4 Patents and trade marks 14
6.2.5 Postal services 14
6.3 Identifiers of objects used in specific industries (“verticals”) 15
6.3.1 Logistics industry 15
6.3.2 Agricultural and food industry 19
6.3.3 Financial industry 24
6.3.4 Healthcare industry 27
6.3.5 Media industry 27
6.3.6 Electronic devices industry 30
6.3.7 Automotive industry 31
6.3.8 Mining industry 32
6.3.9 Chemical industry 33
6.3.10 Land administration and real estate 33
Annex A (informative) Identifier standards as issued by government agencies and SDOs 34
Annex B (informative) Identifier categories 35
Annex C (informative) List of agricultural vocabularies published by ISO 36
7 Bibliography Error! Bookmark not defined.

Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Space After: 0 pt, Line spacing: single
© ISO 20212023 – All rights reserved v

---------------------- Page: 5 ----------------------
ISO /PRF TR 6039:2021(X2023(E)
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Foreword
Formatted: Space After: 0 pt, Line spacing: single
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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 ISO documentsdocument should be noted. This document was drafted in accordance
with the editorial rules of the ISO/IEC Directives, Part 2 (see
www.iso.org/directiveswww.iso.org/directives).
Attention is drawnISO draws attention to the possibility that some of the elementsimplementation of this
document may beinvolve the subjectuse of (a) patent(s). ISO takes no position concerning the evidence,
validity or applicability of any claimed patent rights. in respect thereof. As of the date of publication of
this document, ISO had not received notice of (a) patent(s) which may be required to implement this
document. However, implementers are cautioned that this may not represent the latest information,
which may be obtained from the patent database available at www.iso.org/patents. ISO 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).
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
Formatted: Font color: Auto
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 307, Blockchain and distributed ledger
Formatted: Font: Italic
technologies.
Formatted: Foreword Text
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.htmlwww.iso.org/members.html.

Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Space After: 0 pt, Line spacing: single
vi © ISO 2021 2023 – All rights reserved

---------------------- Page: 6 ----------------------
Standard  ISO/PRF TR 6039:2021(X2023(E)
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: 11 pt, Bold
Introduction
Formatted: Left, Space After: 0 pt, Line spacing: single
This document, which is on the available standards and registers of identifiers of subjects and objects
willissued by government agencies and standard development organizations (SDOs) (see Annex A), is
intended to support designers with the innovation process for their development of (international)
blockchain systems for multiple purposes. It also supports the interoperability of those systems with non-
blockchain systems because identifiers are mission critical building blocks of information technology
systems including the blockchain systems.
Identifiers are the data connectors between systems of (public and private) market participants that
communicate with each other. Identifiers can identify “subjects” (with rights and obligations) or “objects”
(without rights and obligations). This distinction is relevant in legal systems of any country in case at
least two subjects of the same or of multiple countries are involved.
This document also includes a clause on “decentralisedSubclause 4.3 addresses decentralized identifiers”
[1]
that leverage blockchain with a reference to the work of(see W3C [1]. ). This document is not a report
on those “decentraliseddecentralized identifiers” standards and registers.
This document is intended to support designers of blockchain and other systems.
Identifiers issued by the public sector and used in information technology systems are mostly products
of a national history (including national legislation) and were mostly not designed for a computer age.
This historical legacy hinders the development of the global standards and registers foron the
identification of subjects and objects.
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Space After: 0 pt, Line spacing: single
© ISO 20212023 – All rights reserved vii

---------------------- Page: 7 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold
Formatted: Left: 1.9 cm, Right: 1.9 cm, Bottom: 1 cm,
Blockchain and distributed ledger technologies — Identifiers of Gutter: 0 cm, Section start: New page, Header distance
from edge: 1.27 cm, Footer distance from edge: 0.5 cm,
subjects and objects for the design of blockchain systems
Numbering: Restart each page
Formatted: Main Title 1, Space After: 0 pt
1 Scope
Formatted: Font: Bold
This document provides an overview of identifiers ([and their standards and register(s)))] relevant for
the design of blockchain systems and the interoperability of those systems with non-blockchain systems.
The following criteria were used for inclusion of identifiers in this document:
— Identifiers (and their standards and registers) issued by the public sector for subjects and objects
Formatted: List Continue 1
such as citizen numbers, business registration numbers or land registration numbers;
— Identifiers that are internationally recognisedrecognized and fulfil one of the following criteria below:
o— IdentifierAn identifier is an international standard of an SDO (Standard Development
Formatted: List Continue 2, No bullets or numbering
Organisation)Organization);
o— IdentifierAn identifier is a de facto standard according to the norms of the industry involved
(even if it is not an international standard of an SDO)).
— Identifiers that have relevance for DLT systems as it fulfils one of the following criteria below:
Formatted: List Continue 1
o— IdentifierAn identifier that has been used without DLT, but has proven to solve the problems
Formatted: List Continue 2, No bullets or numbering
of DLT services using DLT;
o— IdentifierAn identifier that was designed with the usage of DLT in mind from the beginning.
2 Normative references
There are no normative references in this document.
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 22739, Blockchain and distributed ledger technologies — Vocabulary
3 Terms and definitions
Formatted: Tab stops: Not at 0.76 cm
For the purposes of this document, the terms and definitions given in ISO 22739 and the following apply.
ISO and IEC maintain terminologicalterminology databases for use in standardization at the following
addresses:
— ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
Formatted: List Continue 1
— IEC Electropedia: available at http://www.electropedia.org/https://www.electropedia.org/

Formatted: Font: 11 pt
3.1
attribute
Formatted: Font: 11 pt
characteristic or property of an entity
Formatted: Footer
© ISO 2021 2023 – All rights reserved 1

---------------------- Page: 8 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold
[SOURCE: ISO/IEC 24760-1:2019, 3.1.3] , modified — Example deleted.]
3.2
credential
set of data presented as evidence of a claimed or asserted identity and/or entitlements
Formatted: Font color: Auto, Pattern: Clear
[SOURCE: ISO/IEC 29115:2013, 3.8], modified — Note to entry deleted.]
Formatted: Pattern: Clear
Formatted: Pattern: Clear
3.3
DID
decentralized Identifieridentifier
Formatted: Font: Bold
DID
globally unique persistent identifier that does not require a centralized registration authority and is often
generated and/or registered cryptographically
Formatted: Font: Not Bold
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.4
decentralized identifier subject
DID subject
entity identified by a DID and described by a DID document
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.5
entity
item inside or outside an information and communication technology system such as a person,
organisationorganization, a device, a subsystem, or a group that has recognizable distinct existence
3.6
identifier
attribute or set of attributes that uniquely characterizes an identity in a domain
Note 1 to entry: An identifier can be a specifically created attribute with a value assigned to be unique within the
domain.
[SOURCE: ISO/IEC 24760-1:2019, 3.1.4], modified — Note to entry deleted.]
3.7
object
entity without rights and obligations
3.8
subject
entity with rights and obligations
3.9
verifiable credential
tamper-evident credential that has authorship that can be cryptographically verified.
Formatted: Default Paragraph Font
Formatted: Font: 11 pt
[SOURCE: W3C Verifiable Credentials Data Model v1.1]
Formatted: Font: 11 pt
Formatted: Footer
2 © ISO 2021 2023 – All rights reserved

---------------------- Page: 9 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold
4 Considerations for the design of blockchain systems
4.1 Introduction
4.1 General
Designers of a blockchain system make choices for the design of their application such as:
— whichWhich subjects will be included in the DLT service?
Formatted: List Continue 1
— areAre the subjects only from one country (such as healthcare insurance) or from multiple countries
(such as for the international supply chain)?
— areAre the identifiers of subjects of the public sector mandatory for the DLT service or are other
options possible (central or decentraliseddecentralized identifiers)?
— whichWhich objects are planned to be included in the DLT service?
— areAre the preferred identifiers standards available?
— areAre the identifier data registers available and accessible?
— doDo the available identifiers and attributes have the required data quality for the DLT service?
— isIs the DLT system and its identifiers intended to be used with two (or more) DLT systems and/or
with non-DLT systems and/or should interoperability of the two or more systems or applications be
ensured to exchange information (data)?
An overview of subjects (natural persons and legal entities) and an overview of objects such as products,
assets, locations, documents, legal rights, and messages are included in this document. Objects are owned
by one or more subjects. In this document the object identifiers are distinguished in object identifiers of
“horizontal industries” (used by any industry) and object identifiers used by “vertical industries” (used
by a specific industry). Annex B provides an overview of identifier categories.
4.2 Reference Architecture
[6]
As specified in ISO/TS 23257:2022 [6], DLT data can be classified according to its source as shown in
Figure 1. Figure 1.
Formatted: Font: 11 pt

Formatted: Font: 11 pt
Formatted: Footer
© ISO 2021 2023 – All rights reserved 3

---------------------- Page: 10 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold

Figure 1 — Figure 1 — Data categories from DLT stakeholder role perspective.
Formatted: Figure title, No bullets or numbering
[6]
The data sources identified here align with the six DLT roles identified in ISO/TS 23257:2022 [6] as
DLT subjects: administrators, users, providers, developers, governors and auditors. Among these,
administrators, users and providers are typically the most relevant roles to use case definition.
Stakeholders achieve their aims by means of role-based interactions with the DLT system: A specific
example could be the data flows of subjects involved in the international supply chain: the exporter and
its bank, the customs of the exporter, the freight forwarders, the customs of the importer, the importer
and its bank, all those subjects need high quality identifiers of their business partners (and so the
customs) involved and of the goods that are shipped.

SOURCE: ISO/TR 3242:2022, Blockchain and distributed ledger technologies – Use cases
Figure
Formatted: Font: 11 pt
Formatted: Font: 11 pt
Formatted: Footer
4 © ISO 2021 2023 – All rights reserved

---------------------- Page: 11 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold

SOURCE: ISO/TR 3242:2022, Figure 4
Figure 2 – — Off-chain/on-chain data flow model
Formatted: Figure title, Indent: Left: 0 cm
The identifier data (and relevant attributes) of subjects and objects are the data connectors to ensure an
efficient end-to-end digital process, mostly via multiple digital ecosystems of the market participants
involved. The passing of reference identifiers in the dataflow across on-chain and off-chain systems
contributes to the immutable, enhanced trust environment of a DLT system.
Interoperability requires high quality and accurate data (including of identifiers) that are key to correctly
recording and tracking the data-related operations of stakeholders to avoid operational risks. There are
[7]
many definitions of data quality. For this document ISO 8000-8:2015 [7] and ISO/IEC 25012:2008 [8]
[8]
are regarded as the bestexcellent references for designers to review the data quality of the identifiers
that they will include in their design. See Reference [9] for more information on attributes.
4.3 DecentralisedDecentralized Identifiers
Designers could consider the use of decentraliseddecentralized identifiers for their DLT systems. In
response to regulatory differences in relation to data privacy (for natural persons identifiers, attributes
and data) and governance across global trade ecosystem, two concepts have emerged to address
compliance: self-sovereign identity management and decentraliseddecentralized identifiers.
DecentralisedDecentralized identifier is an old and established concept. Examples include using a public
[10]
key or a transformation of it as an identifier and using Universally Unique Identifier [10]. Many
addresses used in blockchain systems, such as for cryptocurrencies fall into this category.
[1]
W3C has published a framework ([Decentralized Identifiers (DIDs) of 19 July 2022 )[1]] acknowledging
a need in some circumstances for a globally unique identifier that is “self-sovereign”, that is, one that does
not depend on any issuing authority and defining DecentralisedDecentralized identifiers (DIDs) as a new
kind of identifier that enables verifiable, decentraliseddecentralized identity.
For the design process, a clear view of which subjects and objects is relevant to consider in the DLT
system and if all market participants involved will be committed to use a DLT system with
decentraliseddecentralized identifiers. The designers need also to understand if the DLT system is a
stand-alone system or needs to interact with other DLT systems and/or with non-DLT systems of one or
more market participants. See Figure 2 [11]See Figure 2 where interoperating DLT and non-DLT systems
can be usefully modelled. Formatted: Font: 11 pt
Formatted: Font: 11 pt
DecentralisedDecentralized identifiers are often used in a verifiable credential and are associated with
subjects such that the verifiable credential can be easily ported from the repository to another without
Formatted: Footer
© ISO 2021 2023 – All rights reserved 5

---------------------- Page: 12 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold
the need to reissue the credential. W3C has defined that anything can be a DID subject: person, group,
organisationorganization, physical thing, digital thing, logical thing, etc.”.”
According to the W3C’s data model, decentralised identifiers (DIDs) are most often used in a verifiable
credential and are associated with subjects such that a verifiable credential itself can be easily ported
from one repository to another without the need to reissue the credential.
The verification of “identifiers (and their attributes)” contained in verifiable credentials with the registers
involved is mission critical to ensure the identification of subjects and objects.
This document does not have verifiable credentials in its scope but it lists categories of identifiers and
attributes that can be contained as claims in verifiable credentials.
5 Identifiers of subjects
5.1 Introduction
5.1 General
The United Nations hasmembers are sovereign states as members [12]. Governments of countries
[12]
approved . Countries stipulate in their legislation how and by whom identifiers for their citizens and
for their legal forms and its legal entities are issued in their countryand who is allowed to use those
identifiers for which public or private purpose. The government agencies involved that issue the
identifiers are regarded the authoritative source of the identifiers and their attributes.
Subjects are entities with rights and obligations according to the legislation of the UN members.country
involved. There are two categories of subjects in any countrycountries: natural persons and legal entities
for which government agencies issue unique identifiers.
Governments agencies use their (unique) identifiers (and attributes) for the communication with their
citizens for their services and for e-government services inclusive for their social benefits programs. For
communication with legal entities, government agencies use the identifier (and attributes) issued by the
business register of their jurisdiction. Government agencies sometimes use additional identifiers for
specific functions such as tax numbers, VAT numbers, etc. Government identifiers are in general an
integral part of the authentication process for citizens and legal entities to get access to e-government
services.
Businesses have their own onboarding process for their customers, suppliers and partners and use a
CRM (Customer Relationship Management) system with identifiers. The identifier is used for many
business processes such as for the invoicing process, reconciliation of payments data, access to the
helpdesks, loyalty schemes and for the authentication of the customers, suppliers and partners to specific
e-commerce or e-service of the business involved. In several industries, an industry identifier is used for
the joint business processes often based on a rulebook, master agreement and/or a common platform.
This chapterclause gives an overview of public and private identifiers (and attributes) designers could
consider to use for their CRM systems and applications
5.2 Identifiers of natural persons
5.2.1 Public sector identifiers
Formatted: List Number 1, Indent: Left: 0 cm, First line:
0 cm, Numbered + Level: 1 + Numbering Style: 1, 2, 3, …
5.2.1.1 National identity number
+ Start at: 1 + Alignment: Left + Aligned at: 0 cm +
Indent at: 0 cm
The United Nations mention that the civil registration systems for the citizens of a jurisdiction have three
basic functions: Formatted: Font: 11 pt
Formatted: Font: 11 pt
1) A legal and administrative function;
Formatted: Footer
6 © ISO 2021 2023 – All rights reserved

---------------------- Page: 13 ----------------------
ISO/PRF TR 6039:2023(E)
Formatted: Font: Bold
2) A statistical function;
3) The identity management function.
The identity management function assumes that civil registration provides accurate input into an identity
management systems or population register. The identity management system also services a legal and
identity function. The legal and administrative function of the provision of credentials that enable
individuals to prove their identity, and the identity management function being the maintenance of a
system for the managing information and credential associated with an identity.
The United Nations stresses that “Everyone has the right to be recognized as a person before the law, as
[13]
enshrined in Article 6Article 6 of the Universal Declaration on Human Rights” [13].” .
The national identification number is used by the government agencies as a means of tracking their
citizens, permanent residents and temporary residents for the purpose of work, taxations, government
benefits, education, healthcare and other official functions. The issuing of the identification number i
...

TECHNICAL ISO/TR
REPORT 6039
First edition
2023-06
Blockchain and distributed ledger
technologies — Identifiers of
subjects and objects for the design of
blockchain systems
Technologies des chaînes de blocs et technologies de registre
distribué — Identifiants des sujets et des objets pour la conception des
systèmes de chaînes de blocs
PROOF/ÉPREUVE
Reference number
ISO/TR 6039:2023(E)
© ISO 2023

---------------------- Page: 1 ----------------------
ISO/TR 6039:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
PROOF/ÉPREUVE © ISO 2023 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/TR 6039:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Considerations for the design of blockchain systems . 2
4.1 General . 2
4.2 Reference Architecture . 3
4.3 Decentralized Identifiers . 4
5  Identifiers of subjects . 5
5.1 General . 5
5.2 Identifiers of natural persons . 5
5.2.1 Public sector identifiers . 5
5.2.2 Private sector identifiers . 6
5.3 Identifiers of legal entities . 6
5.3.1 Public sector identifiers . 6
5.3.2 Private sector identifiers . 8
6  Identifiers of objects .9
6.1 Introduction . 9
6.2 Identifiers of objects used in multiple industries (“horizontals”) . 10
6.2.1 Supply chain. 10
6.2.2 Telecom .13
6.2.3 Internet . 15
6.2.4 Patents and trade marks . 16
6.2.5 Postal services . 16
6.3 Identifiers of objects used in specific industries (“verticals”) . 16
6.3.1 Logistics industry . . 16
6.3.2 Agricultural and food industry . 20
6.3.3 Financial industry . 26
6.3.4 Healthcare industry .28
6.3.5 Media industry .29
6.3.6 Electronic devices industry . 31
6.3.7 Automotive industry . 32
6.3.8 Mining industry .34
6.3.9 Chemical industry .34
6.3.10 Land administration and real estate . 35
Annex A (informative)  Identifier standards as issued by government agencies and SDOs .36
Annex B (informative)  Identifier categories .37
Annex C (informative)  List of agricultural vocabularies published by ISO .38
Bibliography .40
iii
© ISO 2023 – All rights reserved PROOF/ÉPREUVE

---------------------- Page: 3 ----------------------
ISO/TR 6039:2023(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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 ISO 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).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
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.
This document was prepared by Technical Committee ISO/TC 307, Blockchain and distributed ledger
technologies.
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.
iv
PROOF/ÉPREUVE © ISO 2023 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/TR 6039:2023(E)
Introduction
This document, which is on the available standards and registers of identifiers of subjects and objects
issued by government agencies and standard development organizations (SDOs) (see Annex A), is
intended to support designers with the innovation process for their development of (international)
blockchain systems for multiple purposes. It also supports the interoperability of those systems
with non-blockchain systems because identifiers are mission critical building blocks of information
technology systems including the blockchain systems.
Identifiers can identify “subjects” (with rights and obligations) or “objects” (without rights and
obligations). This distinction is relevant in legal systems of any country in case at least two subjects of
the same or of multiple countries are involved.
[1]
Subclause 4.3 addresses decentralized identifiers that leverage blockchain (see W3C ). This document
is not a report on those “decentralized identifiers” standards and registers.
This document is intended to support designers of blockchain and other systems.
Identifiers issued by the public sector and used in information technology systems are mostly products
of a national history (including national legislation) and were mostly not designed for a computer age.
This historical legacy hinders the development of global standards and registers on the identification of
subjects and objects.
v
© ISO 2023 – All rights reserved PROOF/ÉPREUVE

---------------------- Page: 5 ----------------------
TECHNICAL REPORT ISO/TR 6039:2023(E)
Blockchain and distributed ledger technologies —
Identifiers of subjects and objects for the design of
blockchain systems
1 Scope
This document provides an overview of identifiers [and their standards and register(s)] relevant for the
design of blockchain systems and the interoperability of those systems with non-blockchain systems.
The following criteria were used for inclusion of identifiers in this document:
— Identifiers (and their standards and registers) issued by the public sector for subjects and objects
such as citizen numbers, business registration numbers or land registration numbers;
— Identifiers that are internationally recognized and fulfil one of the following criteria:
— An identifier is an international standard of an SDO (Standard Development Organization);
— An identifier is a de facto standard according to the norms of the industry involved (even if it is
not an international standard of an SDO).
— Identifiers that have relevance for DLT systems as it fulfils one of the following criteria:
— An identifier that has been used without DLT, but has proven to solve the problems of DLT
services using DLT;
— An identifier that was designed with the usage of DLT in mind from the beginning.
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 22739, Blockchain and distributed ledger technologies — Vocabulary
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 22739 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
attribute
characteristic or property of an entity
[SOURCE: ISO/IEC 24760-1:2019, 3.1.3, modified — Example deleted.]
1
© ISO 2023 – All rights reserved PROOF/ÉPREUVE

---------------------- Page: 6 ----------------------
ISO/TR 6039:2023(E)
3.2
credential
set of data presented as evidence of a claimed or asserted identity and/or entitlements
[SOURCE: ISO/IEC 29115:2013, 3.8, modified — Note to entry deleted.]
3.3
decentralized identifier
DID
globally unique persistent identifier that does not require a centralized registration authority and is
often generated and/or registered cryptographically
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.4
decentralized identifier subject
DID subject
entity identified by a DID and described by a DID document
[SOURCE: W3C Decentralized Identifiers (DIDs) v1.0]
3.5
entity
item inside or outside an information and communication technology system such as a person,
organization, a device, a subsystem, or a group that has recognizable distinct existence
3.6
identifier
attribute or set of attributes that uniquely characterizes an identity in a domain
Note 1 to entry: An identifier can be a specifically created attribute with a value assigned to be unique within the
domain.
[SOURCE: ISO/IEC 24760-1:2019, 3.1.4, modified — Note to entry deleted.]
3.7
object
entity without rights and obligations
3.8
subject
entity with rights and obligations
3.9
verifiable credential
tamper-evident credential that has authorship that can be cryptographically verified
[SOURCE: W3C Verifiable Credentials Data Model v1.1]
4  Considerations for the design of blockchain systems
4.1 General
Designers of a blockchain system make choices for the design of their application such as:
— Which subjects will be included in the DLT service?
— Are the subjects only from one country (such as healthcare insurance) or from multiple countries
(such as for the international supply chain)?
2
PROOF/ÉPREUVE © ISO 2023 – All rights reserved

---------------------- Page: 7 ----------------------
ISO/TR 6039:2023(E)
— Are the identifiers of subjects of the public sector mandatory for the DLT service or are other options
possible (central or decentralized identifiers)?
— Which objects are planned to be included in the DLT service?
— Are the preferred identifiers standards available?
— Are the identifier data registers available and accessible?
— Do the available identifiers and attributes have the required data quality for the DLT service?
— Is the DLT system and its identifiers intended to be used with two (or more) DLT systems and/or
with non-DLT systems and/or should interoperability of the two or more systems or applications be
ensured to exchange information (data)?
An overview of subjects (natural persons and legal entities) and an overview of objects such as products,
assets, locations, documents, legal rights, and messages are included in this document. Objects are
owned by one or more subjects. In this document the object identifiers are distinguished in object
identifiers of “horizontal industries” (used by any industry) and object identifiers used by “vertical
industries” (used by a specific industry). Annex B provides an overview of identifier categories.
4.2  Reference Architecture
[6]
As specified in ISO 23257, DLT data can be classified according to its source as shown in Figure 1.
Figure 1 — Data categories from DLT stakeholder role perspective
[6]
The data sources identified here align with the six DLT roles identified in ISO 23257 as DLT subjects:
administrators, users, providers, developers, governors and auditors. Among these, administrators,
users and providers are typically the most relevant roles to use case definition. Stakeholders achieve
their aims by means of role-based interactions with the DLT system: A specific example could be the
data flows of subjects involved in the international supply chain: the exporter and its bank, the customs
of the exporter, the freight forwarders, the customs of the importer, the importer and its bank, all those
subjects need high quality identifiers of their business partners (and so the customs) involved and of
the goods that are shipped.
3
© ISO 2023 – All rights reserved PROOF/ÉPREUVE

---------------------- Page: 8 ----------------------
ISO/TR 6039:2023(E)
SOURCE: ISO/TR 3242:2022, Figure 4
Figure 2 — Off-chain/on-chain data flow model
The identifier data (and relevant attributes) of subjects and objects are the data connectors to ensure an
efficient end-to-end digital process, mostly via multiple digital ecosystems of the market participants
involved. The passing of reference identifiers in the dataflow across on-chain and off-chain systems
contributes to the immutable, enhanced trust environment of a DLT system.
Interoperability requires high quality and accurate data (including of identifiers) that are key to
correctly recording and tracking the data-related operations of stakeholders to avoid operational risks.
[7] [8]
There are many definitions of data quality. ISO 8000-8 and ISO/IEC 25012 are excellent references
for designers to review the data quality of the identifiers that they will include in their design.
4.3  Decentralized Identifiers
Designers could consider the use of decentralized identifiers for their DLT systems. In response to
regulatory differences in relation to data privacy (for natural persons identifiers, attributes and data)
and governance across global trade ecosystem, two concepts have emerged to address compliance: self-
sovereign identity management and decentralized identifiers.
Decentralized identifier is an old and established concept. Examples include using a public key or a
[10]
transformation of it as an identifier and using Universally Unique Identifier. Many addresses used in
blockchain systems, such as for cryptocurrencies fall into this category.
[1]
W3C has published a framework [Decentralized Identifiers (DIDs) of 19 July 2022] acknowledging
a need in some circumstances for a globally unique identifier that is “self-sovereign”, that is, one that
does not depend on any issuing authority and defining Decentralized identifiers (DIDs) as a new kind of
identifier that enables verifiable, decentralized identity.
For the design process, a clear view of which subjects and objects is relevant to consider in the DLT
system and if all market participants involved will be committed to use a DLT system with decentralized
identifiers. The designers need also to understand if the DLT system is a stand-alone system or needs to
interact with other DLT systems and/or with non-DLT systems of one or more market participants. See
Figure 2 where interoperating DLT and non-DLT systems can be usefully modelled.
Decentralized identifiers are often used in a verifiable credential and are associated with subjects such
that the verifiable credential can be easily ported from the repository to another without the need to
reissue the credential. W3C has defined that anything can be a DID subject: person, group, organization,
physical thing, digital thing, logical thing, etc.”
4
PROOF/ÉPREUVE © ISO 2023 – All rights reserved

---------------------- Page: 9 ----------------------
ISO/TR 6039:2023(E)
The verification of “identifiers (and their attributes)” contained in verifiable credentials with the
registers involved is mission critical to ensure the identification of subjects and objects.
This document does not have verifiable credentials in its scope but it lists categories of identifiers and
attributes that can be contained as claims in verifiable credentials.
5  Identifiers of subjects
5.1 General
[12]
The United Nations members are sovereign states. Countries stipulate in their legislation how
identifiers for their citizens and legal entities are issued and who is allowed to use those identifiers
for which public or private purpose. The government agencies involved that issue the identifiers are
regarded the authoritative source of the identifiers and their attributes.
Subjects are entities with rights and obligations according to the legislation of the country involved.
There are two categories of subjects in countries: natural persons and legal entities for which
government agencies issue unique identifiers.
Governments agencies use their (unique) identifiers (and attributes) for the communication with their
citizens for their services and for e-government services inclusive for their social benefits programs.
For communication with legal entities, government agencies use the identifier (and attributes) issued
by the business register of their jurisdiction. Government agencies sometimes use additional identifiers
for specific functions such as tax numbers, VAT numbers, etc. Government identifiers are in general an
integral part of the authentication process for citizens and legal entities to get access to e-government
services.
Businesses have their own onboarding process for their customers, suppliers and partners and use
a CRM (Customer Relationship Management) system with identifiers. The identifier is used for many
business processes such as the invoicing process, reconciliation of payments data, access to helpdesks,
loyalty schemes and the authentication of the customers, suppliers and partners to specific e-commerce
or e-service of the business involved. In several industries, an industry identifier is used for joint
business processes often based on a rulebook, master agreement and/or a common platform.
This clause gives an overview of public and private identifiers (and attributes) designers could consider
to use for their CRM systems and applications
5.2  Identifiers of natural persons
5.2.1  Public sector identifiers
5.2.1.1 National identity number
The United Nations mention that the civil registration systems for the citizens of a jurisdiction have
three basic functions:
1) A legal and administrative function;
2) A statistical function;
3) The identity management function.
The identity management function assumes that civil registration provides accurate input into an
identity management systems or population register. The identity management system also services a
legal and identity function. The legal and administrative function of the provision of credentials enable
individuals to prove their identity.
The United Nations stresses that “Everyone has the right to be recognized as a person before the law, as
[13]
enshrined in Article 6 of the Universal Declaration on Human Rights” .
5
© ISO 2023 – All rights reserved PROOF/ÉPREUVE

---------------------- Page: 10 ----------------------
ISO/TR 6039:2023(E)
The national identification number is used by government agencies as a means of tracking their citizens,
permanent residents and temporary residents for the purpose of work, taxations, government benefits,
education, healthcare and other official functions. The issuing of the identification number is stipulated
by the legislation of the country involved. Each country has its own standard for the identifier (and
attributes) of the citizen record. The access to registers with citizens data is limited by the laws of
the country involved. The UN published guidelines on the legislative framework for civil registrations.
[14]
The UN publishes no overview of “national identification numbers”. See Reference [15] for more
information on national identification numbers.
The OECD provides an overview of “tax identification numbers” (TIN) of many of the UN member
countries, or the functional equivalent for their citizens with the rules of the country involved in
relation to the issuance, structure, use and validity of its TIN. See Reference [16] for more information.
The authentication schemes of/for government agencies include directly or indirectly the citizen
number issued by the government involved.
5.2.1.2 Passport
The ICAO (International Civil Aviation Organization) issues the specifications for machine readable
passports. A passport is a travel document (so an object) issued by a government, primarily for the
[17]
purpose of travel, to certify the personal identity and nationality of its holder. The ICAO specifications
include mandatory data elements such as:
— the issuing state or organization (in code);
— the passport number must uniquely identify the document from all other machine readable
documents issued by the state;
— a primary and a secondary identifier as defined by the state.
[18]
ISO/IEC 7501-1 defines machine readable passports.
5.2.2  Private sector identifiers
Businesses and NGOs design(ed) their own identifier (and attributes) for the registration of their
natural person customers or members. These identifiers can include industry standards (such as part
of the credit card number). Businesses (such as organizations in the financial industry) must also
often include an identifier issued by a public sector agency of the country involved in the files of their
customers. These identifiers mostly can only be used for specific purposes allowed or prescribed by the
legislation of the country involved.
5.2.2.1  ISO 24366 Financial services — Natural Person Identifier (NPI)
[19]
ISO 24366 specifies a machine-readable, unambiguous natural person identifier (NPI) and the
relevant reference data to uniquely identify the natural person relevant to any financial transaction
rather than the personal identifying information.
5.3  Identifiers of legal entities
5.3.1  Public sector identifiers
5.3.1.1  Identifiers of legal entities registered in business registers
All countries have legal entities (with rights and obligations) of several legal forms (see 5.3.2.1) that are
in general registered with an identifier in a business register or other public register of that country.
Not all countries have a complete register of all legal entities of all their legal forms. All business
registers have their own (national) identifier standard for legal entities and do not use a standard of an
international SDO (Standard Development Organization). All business registers have their own rules on
the access to the data of legal entities and if a fee is required to get access to (part of) the data.
6
PROOF/ÉPREUVE © ISO 2023 – All rights reserved

---------------------- Page: 11 ----------------------
ISO/TR 6039:2023(E)
The G20-FSB mandated the Global Legal Entity Identifier Foundation (GLEIF) to take care of the
[20]
“Registration Authorities List”, which includes over 770 business registers, and other relevant
registers of which the data are available free of charge for any user. The register of the Registration
Authorities is available.
[16]
The OECD makes an overview available to many UN member countries of their “tax identification
numbers” (TIN) for legal entities or their functional equivalents with the rules of the country involved
in relation to the issuance, structure, use and validity of its TIN.
5.3.1.2  ISO 20275 Financial ser
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.