ISO/IEC 21617-1:2026

• Abstract:

  This document specifies a framework for establishing trust in media. This framework includes aspects of authenticity, provenance, attribution, intellectual property rights, and integrity through secure and reliable annotation of the media assets throughout their life cycle.

• Status: Published
• Publication Date: 25-Aug-2026
• ICS: 35.040.30 - Coding of graphical and photographical information
• Technical Committee: ISO/IEC JTC 1/SC 29 - Coding of audio, picture, multimedia and hypermedia information
• Drafting Committee: ISO/IEC JTC 1/SC 29/WG 1 - JPEG Coding of digital representations of images
• Current Stage: 6060 - International Standard published
• Start Date: 26-Aug-2026
• Due Date: 28-Jan-2027
• Completion Date: 26-Aug-2026

• Revises: ISO/IEC 21617-1:2025 - Information technology — JPEG Trust — Part 1: Core foundation
• Effective Date: 13-Feb-2026

Overview

ISO/IEC 21617-1:2026 – Information technology - JPEG Trust - Part 1: Core foundation establishes a framework for building trust in digital media assets throughout their entire life cycle. Developed by ISO/IEC JTC 1/SC 29, this international standard specifies foundational requirements for annotating, managing, and validating aspects such as authenticity, provenance, attribution, intellectual property rights (IPR), and integrity of media assets, using secure and reliable methodologies.

This document addresses increasing global concerns about manipulated, synthetic, or misleading media (including the impact of deepfakes and misinformation), while supporting legal and creative workflows. It enables organizations and creators to embed, manage, and verify trust-related information using interoperable standards, fostering digital trust and transparency across various domains.

Key Topics

• JPEG Trust Framework: Outlines components for securing trust, including the Trust Record, Trust Manifest, Trust Indicators, Trust Profile, and Trust Report for thorough documentation of asset history and authenticity.
• Assertions and Metadata: Enables creation and validation of assertions about a media asset, including what changes occurred, who made them, when, and how. Supports integration with existing metadata standards (e.g., Exif, IPTC).
• Provenance and Attribution: Provides mechanisms to capture and disclose provenance, including creator and modification details, supporting attribution and IPR claims.
• Embedding and Referencing: Defines methods for embedding trust manifests within JPEG file formats (JPEG 1, JPEG 2000, JPEG XL, JPEG XS, etc.) using the JPEG Universal Metadata Box Format (JUMBF), as well as referencing external manifests.
• Content Binding and Integrity: Utilizes cryptographic bindings (hashes), digital signatures, and timestamps to bind trust assertions to specific media content, ensuring data integrity and traceability.
• Privacy and Protection: Includes provisions for anonymization and obfuscation, balancing transparency with privacy and data protection requirements.
• Interoperability and Flexibility: Supports user-defined trust profiles, allowing different industries or communities to apply suitable trust models according to their needs.

Applications

ISO/IEC 21617-1:2026 supports a broad range of applications where trust in digital media assets is critical, including:

• Media and News Organizations: Trace and assert the authenticity and provenance of images to counter misinformation and build audience trust.
• Digital Rights Management (DRM): Enable declaration and enforcement of intellectual property rights for photographers, artists, and content owners.
• Social Media Platforms and Content Sharing: Implement mechanisms to detect and signal manipulated or synthetic content, enabling informed sharing and content moderation.
• Legal and Compliance Contexts: Provide verifiable evidence trails for media authenticity and modification history, useful in litigation or regulatory audits.
• Cultural Heritage and Scientific Research: Document and preserve integrity, provenance, and usage rights of digital assets in archives, museums, and research institutions.
• AI-generated Content: Annotate and disclose synthetic content creation, enhancing transparency in media produced by algorithms or deep learning models.

Related Standards

ISO/IEC 21617-1:2026 references and is designed to work in conjunction with several important standards:

• ISO/IEC 10918-1:1994 – Digital compression and coding of continuous-tone still images (JPEG)
• ISO/IEC 15444-1:2024 – JPEG 2000 image coding system
• ISO/IEC 18181-2:2024 – JPEG XL image coding system
• ISO/IEC 18477 series – JPEG XT and JPEG Pleno for scalable image coding
• ISO/IEC 19566 series – JPEG Systems components, including JUMBF for universal metadata, privacy, and security
• ISO/IEC 21122-1 – JPEG XS low-latency image coding
• W3C ODRL – Rights expression language for digital permissions
• C2PA Technical Specification – Content provenance framework
• IETF RFCs – Including standards for cryptographic time-stamping and data encoding

Following ISO/IEC 21617-1:2026 ensures compatibility and interoperability with these and other media trust and metadata standards, positioning implementers at the forefront of secure, credible digital content management.

International
Standard
ISO/IEC 21617-1
Second edition
Information technology — JPEG
2026-08
Trust —
Part 1:
Core foundation
Reference number
© ISO/IEC 2026
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
© ISO/IEC 2026 – All rights reserved
ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 JPEG Trust framework . 6
4.1 Description .6
4.2 Overview .6
4.3 Trust Record .7
4.4 Trust Manifests .8
4.4.1 General .8
4.4.2 Components of a Trust Manifest .9
4.4.3 Details of a Trust Manifest . .9
4.4.4 Trust Declaration .10
4.5 Trust Indicators .10
4.5.1 General .10
4.5.2 Trust Indicator Set .10
4.6 Trust Profile .10
4.7 Trust Report .11
4.7.1 General .11
4.7.2 Trust Report generation procedure .11
4.7.3 Trust Report Assertion . 12
5 Assertions.12
5.1 Introduction . 12
5.1.1 Overview . 12
5.1.2 Description . 13
5.2 Assertion metadata . 13
5.2.1 General . 13
5.2.2 When (date and time) . 13
5.2.3 Extent of modification(s) . .14
5.3 Actions .14
5.3.1 Description .14
5.3.2 Type of modification .14
5.3.3 Region of interest . 15
5.3.4 Purpose of modification(s) . 15
5.3.5 How was it created . 15
5.3.6 Category of modifications . 15
5.4 Bindings (hashes) . .16
5.4.1 General .16
5.4.2 Hard bindings .16
5.4.3 Soft bindings .16
5.5 Using existing metadata standards .16
5.5.1 Exif .16
5.5.2 IPTC .17
5.6 Intellectual property rights .17
5.6.1 General .17
5.6.2 Identity .17
5.6.3 Rights . . . 20
5.6.4 IPR Examples . 22
6 Embedding and referencing.23
6.1 Use of JUMBF . 23
6.2 Embedding manifests into JPEG assets .24
6.2.1 Embedding manifests into JPEG 1 and JPEG XT.24

© ISO/IEC 2026 – All rights reserved
iii
6.2.2 Embedding manifests into JPEG XL .24
6.2.3 Embedding manifests into JPEG 2000 . . 25
6.2.4 Embedding manifests into JPEG XS . 25
6.3 Embedding manifests into other asset types . 25
6.4 External manifests . 26
6.5 Embedding a reference to the active manifest . 26
7 Media asset content binding .26
7.1 General . 26
7.2 Cryptographic binding to content . 26
7.3 Content hash .27
7.4 Use of digital signatures .27
7.5 Use of timestamps .27
7.6 Validation .27
8 Privacy and protection .28
8.1 General . 28
8.2 Anonymization . 28
8.2.1 Redaction . 28
8.3 Obfuscation . 29
8.3.1 General . 29
8.3.2 Protecting an assertion . 29
8.3.3 Protecting the media asset content .32
Annex A (normative) Serialisation of Trust Indicator Sets .34
Annex B (normative) Serialisation of Trust Profiles . 47
Annex C (normative) Serialisation of Trust Reports .60
Annex D (informative) Using Dublin Core metadata with JPEG Trust .64
Annex E (informative) Relationship between this document (JPEG Trust) and Content
Credentials . 67
Annex F (informative) Threat vectors .68
Annex G (informative) Change history .71
Bibliography .72

© ISO/IEC 2026 – All rights reserved
iv
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 https://www.iso.org/directives or https://www.iec.ch/members_experts/refdocs).
ISO and IEC draw attention to the possibility that the implementation of this document may involve the
use of (a) patent(s). ISO and IEC take 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 and IEC had
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 https://www.iso.org/patents and https://patents.iec.ch. ISO and IEC 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 https://www.iso.org/iso/foreword.html. In
the IEC, see https://www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information.
This second edition cancels and replaces the first edition (ISO/IEC 21617:2025), which has been technically
revised.
The main changes are as follows:
— A new Annex D has been added to where details of the changes made in this edition can be found.
A list of all parts in the ISO/IEC 21617 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 https://www.iso.org/members.html and
https://www.iec.ch/national-committees.

© ISO/IEC 2026 – All rights reserved
v
Introduction
Current technologies enable the modification or synthetic creation of media assets. Some, like deep learning
methods, can create media assets that are hard for people to distinguish from natural media assets. These
technologies open new, creative opportunities that are useful for business and research usage. However,
these technologies can also lead to issues relating to the use of manipulated media assets to spread
misinformation or disinformation. Misuse of manipulated media assets can cause social unrest, spread
rumours for political gain, or encourage hate crimes.
Media modifications are not always negative as they are increasingly a normal and legal component of many
production pipelines. However, in many application domains, creators need or want to declare the type of
modifications that were performed on the media asset. A lack of such declarations in these situations may
reveal the lack of trustworthiness of media assets or the intention to hide the existence of manipulations.
To address such problems and attempt to avoid negative impacts, some companies, including social media
platforms and news outlets, are developing mechanisms to clearly detect and annotate manipulated media
assets when they are shared.
There is a need to have a standardized way to annotate media assets (regardless of the intent) and securely
link the assets and annotations together. This document (JPEG Trust) ensures interoperability between a
wide range of applications dealing with media asset creation and modification, providing a set of standard
mechanisms to describe and embed information about the creation and modification of media assets.
Furthermore, a key aspect of understanding the trustworthiness of a media asset is the nature of trust
itself. No single trust model can accommodate all the expressions of media asset trust in society so this
document (JPEG Trust) requires a flexible architecture for accommodating diverse trust models. Through
the mechanism of user-defined trust profiles, this document empowers various communities to define trust
models that meet the specific demands of their trust requirements.
This document (JPEG Trust) provides a comprehensive framework for individuals, organizations, and
governing institutions interested in establishing an environment of trust for the media that they use, and
to support trust in the media they share online. This framework addresses aspects of providing provenance
information, assertion rights, extracting and evaluating trust indicators, and handling privacy and security
concerns.
This is the second edition of this document (JPEG Trust). It has been updated to reflect the latest
developments in the field of media provenance and to provide a framework for the declaration of intellectual
property rights. Details of the changes made in this edition can be found in Annex G.

© ISO/IEC 2026 – All rights reserved
vi
International Standard ISO/IEC 21617-1:2026(en)
Information technology — JPEG Trust —
Part 1:
Core foundation
1 Scope
This document specifies a framework for establishing trust in media. This framework includes aspects of
authenticity, provenance, attribution, intellectual property rights, and integrity through secure and reliable
annotation of the media assets throughout their life cycle.
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 18181-2:2024, Information technology — JPEG XL image coding system — Part 2: File format
ISO/IEC 18477-1, Information technology — Scalable compression and coding of continuous-tone still images —
Part 1: Core coding system specification
ISO/IEC 18477-3, Information technology — Scalable compression and coding of continuous-tone still images —
Part 3: Box file format
ISO/IEC 19566-4, Information technologies — JPEG systems — Part 4: Privacy and security
ISO/IEC 19566-5:2023, Information technologies — JPEG systems — Part 5: JPEG universal metadata box
format (JUMBF)
ISO/IEC 19566-6, Information technologies — JPEG systems — Part 6: JPEG 360
ISO/IEC 19566-7, Information technologies — JPEG systems — Part 7: JPEG linked media format (JLINK)
ISO/IEC 19566-8, Information technologies — JPEG systems — Part 8: JPEG Snack
ISO/IEC 21122-1, Information technology — JPEG XS low-latency lightweight image coding system — Part 1:
Core coding system
Rec. ITU-T T.81 (1992) | ISO/IEC 10918-1:1994, Information technology — Digital compression and coding of
continuous-tone still images: Requirements and guidelines
Rec. ITU-T T.800 (v4) (07/24) | ISO/IEC 15444-1:2024, Information technology — JPEG 2000 image coding
system — Part 1: Core coding system
1)
IETF RFC 4648, The Base16, Base32, and Base64 Data Encodings. RFC Series
2)
IETF RFC 8141, Uniform Resource Names (URNs). RFC Series
W3C Recommendation JSON-LD, JSON-LD 1.1, https:// www .w3 .org/ TR/ json -ld11/
1) Available from: https:// www .rfc -editor .org/ info/ rfc4648.
2) Available from: https:// www .rfc -editor .org/ info/ rfc8141.

© ISO/IEC 2026 – All rights reserved
ODRL Information Model. W3C ODRL Information Model 2.2, https:// www .w3 .org/ TR/ odrl -model/
Vocabulary Expression ODRL, W3C ODRL Vocabulary & Expression 2.2, https:// www .w3 .org/ TR/ odrl
-vocab/
C2PA Technical Specification, C2PA Technical Specification 2.3, Coalition for Content Provenance and
Authenticity, https:// c2pa .org/ specifications/ specifications/ 2 .3/ specs/ C2PA _Specification .html
json-formula, json-formula: A Query Language for JSON with Spreadsheet Functions, https:// opensource .adobe
.com/ json -formula/
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
actor
actors
human or non-human (hardware or software) that is participating in the media ecosystem
EXAMPLE camera (capture device), generation or editing software, cloud service or the person using such tools
3.2
anonymization
process of altering data in a media asset with the aim to protect the privacy of an actor (3.1) by obscuring
identifiable features
3.3
assertion
data structure which represents a statement asserted by an actor (3.1) concerning the media asset (3.19)
Note 1 to entry: This data is a part of the trust manifest (3.40).
[SOURCE: C2PA Technical Specification]
3.4
authentic media asset
authenticity of media asset
media asset (3.19) that is verifiable (3.45)
3.5
author
human whose creativity led to a work being created or modified
3.6
claim
digitally signed and tamper-evident data structure that references one or more assertion (3.3) by one or
more actors (3.1), concerning a media asset (3.19), and the information necessary to represent the content
binding. If any assertion was redacted, then a declaration to that effect is included
Note 1 to entry: This data is a part of the trust manifest (3.40).
[SOURCE: C2PA Technical Specification]

© ISO/IEC 2026 – All rights reserved
3.7
claim signature
digital signature on the claim (3.6) using the private key of an actor (3.1)
Note 1 to entry: The claim_signature is a part of the trust manifest (3.40).
[SOURCE: C2PA Technical Specification]
3.8
composed media asset
media asset (3.19) composed of multiple media assets
3.9
content binding
information that associates media asset content (3.20) to a specific trust record (3.42) associated with a
specific media asset (3.19), either as a hard binding (3.13) or a soft binding (3.36)
[SOURCE: C2PA Technical Specification]
3.11
fingerprint
set of inherent properties computable from media asset content (3.20) that identifies the content or near
duplicates of it
[SOURCE: C2PA Technical Specification]
3.12
generative AI media asset
synthetic media asset
media asset (3.19) created by means of artificial intelligence (AI) and machine learning (ML)
3.13
hard binding
one or more cryptographic hashes that uniquely identifies either the entire media asset (3.19) or a portion
thereof
[SOURCE: C2PA Technical Specification]
3.14
intellectual property rights
IPR
exclusive rights of the actor (3.1) to the intellectual work of their creation
3.15
invisible watermark
information incorporated in a substantially human imperceptible way into the media asset content (3.20)
of an media asset (3.19) which can be used, for example, to uniquely identify the media asset or to store a
reference to a trust record (3.42)
[SOURCE: C2PA Technical Specification]
3.16
JPEG 1
common image compression data format and means of reference to Rec. ITU-T T.81 (1992) |
ISO/IEC 10918-1:1994
3.17
JUMBF
universal format to embed any type of metadata in any box-based JPEG file format and means of reference to
ISO/IEC 19566-5:2023
© ISO/IEC 2026 – All rights reserved
3.18
manipulated media asset
manipulated media
media asset (3.19) that has been changed with the intention to induce misinterpretation
3.19
media asset
digital assets including images, videos, audio or text
3.20
media asset content
portion of a media asset (3.19) that represents the actual content, such as the pixel data of an image, along
with any additional technical metadata required to understand or render the content (e.g., a colour profile
or encoding parameters)
3.21
media asset integrity
lack of corruption of a media asset (3.19)
3.22
media asset metadata
portion of a media asset (3.19) that represents non-technical information about the media asset or its content,
such as location, creator, annotations or IPR information
3.23
media asset original
media asset (3.19) produced by a device or method without any modifications
3.24
media asset provenance
set of information about a media asset (3.19) including the trail of modifications starting from an actor (3.1)
EXAMPLE The media asset origin.
Note 1 to entry: Modifications that are missing from the asset’s provenance are treated the same as an invalid or
unverifiable provenance chain.
3.25
media asset source
non-human actor (3.1) that created the media asset original (3.23)
3.26
modified media asset
media asset (3.19) that has been changed
3.27
natural media asset
sensor acquired media asset
3.28
obfuscation
process of altering data in a media asset with the aim to protect unauthorized access
3.29
provenance
logical concept of understanding the history of a media asset (3.19) and its interaction with actor (3.1)s and
other media assets, as represented by the provenance data (3.30)
[SOURCE: C2PA Technical Specification]

© ISO/IEC 2026 – All rights reserved
3.30
provenance data
set of trust record (3.42)s for a media asset (3.19) and, in the case of a composed asset, its ingredients
[SOURCE: C2PA Technical Specification]
3.31
region of interest
ROI
subset within the media asset content (3.20) identified for a particular purpose
EXAMPLE the face portion of a portrait image, an extracted foreground object(s) or scene cuts of a video
3.33
registration
process of storing information (e.g. media asset, metadata or provenance) about a media asset (3.19),
separate from the media asset itself
3.34
signer
actor (3.1) who digitally signs a media asset (3.19)
3.35
signing
process that establishes the relation between an actor (3.1) and a media asset (3.19) in a tamper-evident
manner
3.36
soft binding
content identifier that is either (a) not statistically unique, such as a fingerprint (3.11), or (b) embedded as an
invisible watermark (3.15) in the identified media asset content (3.20)
[SOURCE: C2PA Technical Specification]
3.37
trust declaration
specific type of trust manifest (3.40) that, when present, is always first in the trust record (3.42)
Note 1 to entry: It represents the actor (3.1) that created the media asset (3.19) and contains only mandatory assertions.
3.38
trust indicators
information derived from a combination of the media asset (3.19) and the trust record (3.42) that indicate a
level of trustworthiness of a media asset in a given context
3.39
trust indicator set
set of trust indicators (3.38) that are derived from a media asset (3.19) and its trust record (3.42)
3.40
trust manifest
set of information about the media asset provenance (3.24) of a media asset (3.19)
Note 1 to entry: A trust manifest is part of a trust record (3.42).
3.41
trust profile
set of expressions that are used to evaluate each trust indicators (3.38) in an given trust indicator set (3.39)
to indicate a level of trustworthiness for a given media asset (3.19)

© ISO/IEC 2026 – All rights reserved
3.42
trust record
collection of one or more trust manifest (3.40) that can either be embedded into a media asset (3.19) or be
external to its media asset
3.43
trust report
result of evaluating a trust indicator set (3.39) against a trust profile (3.41)
3.44
trustworthy
able to be relied on as being what it is asserted to be
3.45
trustworthy media asset
media asset (3.19) that is trustworthy (3.44)
3.46
verifiable
able to be checked
4 JPEG Trust framework
4.1 Description
This document describes a framework for establishing trust in media that complies with the JPEG standards
developed by ISO/IEC JTC1 SC 29 including (Rec. ITU-T T.81 (1992) | ISO/IEC 10918 (JPEG 1), Rec. ITU-T
T.800 (v4) (07/24) | ISO/IEC 15444-1 (JPEG 2000), ISO/IEC 18477-1 (JPEG XT), ISO/IEC 18181-2 (JPEG XL),
ISO/IEC 21122-1 (JPEG XS), ISO/IEC 19566-6 (JPEG 360), ISO/IEC 19566-7 (JLINK) and ISO/IEC 19566-8
(JPEG Snack)). The core components of the framework are built on the JPEG Universal Metadata Box Format
(JUMBF), as described in 6.1. Therefore, the core principles can also be applied on other types of media that
can embed JUMBF containers. The model for storing and accessing cryptographically verifiable information
about a media asset is aligned with the technical aspects of Content Credentials.
NOTE For more information about the relationship between this document (JPEG Trust) and Content Credentials,
see Annex E.
4.2 Overview
The JPEG Trust framework establishes that a media asset consists of the media asset content, media asset
metadata, and a Trust Record. The Trust Record (4.3) consists of a one or more Trust Manifests. Each Trust
Manifest is a tamper-evident unit that contains a series of statements, called assertions, that cover areas,
such as asset creation, creation device details, authorship, edit actions, bindings to content and other
information associated with the media asset.
A set of Trust Indicators (4.5) can be derived from the trust record as well as from other metadata or the
media asset content. These Trust Indicators are gathered together into a Trust Indicator Set (4.5.2), which
can be used to assess the trustworthiness of a media asset in a given context through the use of a specified
Trust Profile (4.6). The result of this evaluation is documented in a Trust Report (4.7).
The framework and its core components are illustrated in Figure 1.

© ISO/IEC 2026 – All rights reserved
Figure 1 — Trust Framework
4.3 Trust Record
The Trust Record is a JUMBF superbox composed of a series of other JUMBF boxes and superboxes, each
identified by their own JUMBF type UUID and label in their JUMBF Description box. The Trust Record
Description box shall have a label of c2pa, a JUMBF type UUID of 0x63327061-0011-0010-8000-00AA00389B71
(c2pa) and shall contain one or more Trust Manifest superboxes (which may be a Trust Manifest or a Trust
Declaration). The Trust Record may also contain JUMBF boxes and superboxes whose JUMBF type UUIDs are
not defined in this document.
NOTE Allowing other boxes and superboxes enables custom extensions to this document (JPEG Trust) as well as
enabling the addition of new boxes in future versions of this document without breaking compatibility.
A Trust Record (see Figure 2) shall contain at least one Trust Manifest. The set of Trust Manifests, as stored
in the asset’s Trust Record, represents its Media Asset Provenance.

© ISO/IEC 2026 – All rights reserved
Figure 2 — Trust Record
4.4 Trust Manifests
4.4.1 General
A Trust Manifest (see Figure 3) is the set of information about the media asset provenance, while a Trust
Declaration is a special type of Trust Manifest with only mandatory assertions that always comes first in the
Trust Record.
© ISO/IEC 2026 – All rights reserved
Figure 3 — Trust Manifest
4.4.2 Components of a Trust Manifest
Each Trust Manifest may contain an Assertions Store (containing one or more assertions), a Claim, and a
Claim Signature.
Assertions are statements about the media asset provenance of a given media asset; such as asset creation,
capture device details, authorship, edit actions, and bindings to content. Assertions are wrapped up with
additional information into a digitally signed entity called a Claim.
Together, these Assertions, Claims, and Signatures are all bound together into the Trust Manifest by a
hardware or software component called a Claim Generator.
4.4.3 Details of a Trust Manifest
The Trust Manifest is a JUMBF superbox composed of a series of other JUMBF boxes and superboxes, each
identified by their own JUMBF type UUID and label in their JUMBF Description box. Depending on the type
of manifest, as listed in C2PA Technical Specification, 11.2 and extended by 4.4.4, the associated JUMBF type
UUID for each Trust Manifest shall be used. In order to enable uniquely identifying each Trust Manifest,
they shall be labelled with a IETF RFC 8141 URN) from the c2pa URN namespace. The Requestable and Label
Present toggles shall both be set in the JUMBF Description box of the Trust Manifest’s JUMBF superbox.
Examples
— urn:c2pa:F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4
— urn:c2pa:F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4:acme
— urn:c2pa:F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4:acme:2_1
— urn:c2pa:F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4::2_1
NOTE More information about the JUMBF structure of Trust Manifests can be found in C2PA Technical Specification.

© ISO/IEC 2026 – All rights reserved
4.4.4 Trust Declaration
A Trust Declaration is a specific type of Trust Manifest (which is specified using the JUMBF type UUID of
0x63326D64-0011-0010-8000-00AA00389B71 (c2md)) that shall only be defined during creation of a media
asset and shall only contain a specific set of mandatory assertions, as well as the Claim and Claim Signature.
These mandatory Assertions are:
— exactly one hard binding assertion;
— either a c2pa.hash.data, c2pa.hash.boxes, c2pa.hash.bmff.v2 or c2pa.hash.bmff.v3 based on the
type of asset and version for which the manifest is destined;
— exactly one actions assertion;
— consisting of a single c2pa.created action that specifies the time of creation and a digitalSourceType
field whose values indicate if it was created by a camera, software tool, human or generative AI.
NOTE The digitalSourceType field will have the value https://cv.iptc.org/newscodes/
digitalsourcetype/trainedAlgorithmicMedia when the media asset is created from scratch by generative
AI. When a generative AI uses existing media assets in addition to newly created ones, then the value of https://
cv.iptc.org/newscodes/digitalsourcetype/compositedWithtrainedAlgorithmicMedia is used.
If a specific workflow requires additional assertions, those requirements can be reflected through the use
of a Trust Profile that may be used to evaluate the Trust Indicator Set of the media assets. For example, a
workflow may require that a media asset contain the date, time and location when it is created.
4.5 Trust Indicators
4.5.1 General
Trust Indicators are parameters that may be used to assess the trustworthiness of a media asset in a given
context. Trust Indicators are derived from at least one or more of the following sources: media asset content,
the trust record, and the media asset metadata. In addition, other sources of Trust Indicators may be used,
such as a GenAI usage detection algorithm.
NOTE While some Trust Indicators are declared in this document, new Trust Indicators can be defined at any
time to suit specific workflows.
There are no required Trust Indicators, per se, though there are some that come from required assertions in
a Trust Manifest, such as information about the validation of the hard binding.
4.5.2 Trust Indicator Set
A Trust Indicator Set consists of Trust Indicators extracted from sources such as the media asset content,
the trust record (if present), and the media asset metadata (if present) of a given media asset.
The Trust Indicator Set should be serialised into a W3C Recommendation JSON-LD object, with fields
representing groupings of the Trust Indicators, as described in Annex A. Additionally, this document
describes how to map well known serialisations to JSON-LD for the purposes of consistent processing by a
validator.
NOTE Other serialisations, whether ephemeral or persistent, are possible, but are not specified in this document.
4.6 Trust Profile
A Trust Profile enables the generation of a Trust Report from a Trust Indicator Set. A Trust Profile contains
a block of information about the Trust Profile and a set of statements that are evaluated against a Trust
Indicator Set. Each statement has an expression/formula that takes one or more Trust Indicators as an input

© ISO/IEC 2026 – All rights reserved
and produces a single output value. The Trust Profile shall be expressed as a series of YAML documents as
described in Annex B.
NOTE Other serialisations, whether ephemeral or persistent, are possible, but are not specified in this document.
4.7 Trust Report
4.7.1 General
A Trust Report is produced from the combination of a Trust Profile and a Trust Indicator Set, thereby
documenting the result of evaluating the Trust Indicator Set against the Trust Profile. The evaluation helps
to assess trustworthiness for a given media asset.
A Trust Report contains a block of information, which is extracted from and identifies the associated Trust
Profile, and a list of statements that are the results of evaluating the statements in the associated Trust
Profile against a given media asset’s Trust Indicator Set.
The Trust Report is serialised as a series of YAML documents, with fields representing the block of
information and the list of statements, as described in Annex C.
A Trust Report assertion can be generated based on the Trust Report, which is then added to a new Trust
Manifest. The new Trust Manifest can be added to update the tru
...