ISCC - History¶

The International Standard Content Code (ISCC) started as a single idea in 2016. Eight years later it became an International Standard, ISO 24138:2024. This page traces that path: from an early experiment in content-based identification, through an open-source prototyping project, to ISO standardization and a role in content provenance and authenticity.

At a glance¶

Origins (2016)¶

The first ideas about a content-derived, similarity-preserving identifier were developed in early 2016 by Titusz Pan. The motivation was a practical gap: digital content is dynamic, granular, and constantly re-encoded as it moves between systems, yet many media industries had no standard way to identify it, and no identifier at all for short-lived or user-generated content such as journalism or images.

The core insight was to invert the usual model of media identifiers. Instead of assigning an identifier to content and tracking that binding by hand, the identifier would be derived from the content itself, so that independent parties could compute the same code for the same content without consulting any registry.

The Content Blockchain Project (2016-2018)¶

Later in 2016, the ISCC found its first home in the Content Blockchain Project, a consortium initiated to research how distributed-ledger technology could serve the content and media ecosystem. The project received funding from Google's Digital News Initiative (DNI) to build a first prototype.

Within this project the ISCC moved from concept to working code:

• 2017: The ISCC was prototyped on "Coblo", a media-focused blockchain built on MultiChain. The first public concept document and the specification repository (then iscc-specs, today iscc-codes) were published in July 2017. By November 2017 the project reached its milestone for the creation of content identifiers.
• 2018: The first public, open-source release of the reference code was published as the iscc Python package (v0.9), followed by the ISCC 1.0 specification. In April 2018 the Content Blockchain prototyping project reached its final milestone, with all results released under open-source licenses.

This phase established the four foundational components that still shape the standard today: a Meta-Code, a Content-Code, a Data-Code, and an Instance-Code.

Recognition and the road to ISO (2019)¶

In 2019 the ISCC moved from an open-source prototype toward a formal international standard, and the push came from outside the project. After the Content Blockchain Project released its results as open source, Julia Constanze Hahn of Beuth Verlag, the publishing house of the German standards body DIN (today DIN Media), came across the work, saw what a content-derived identifier could do, and reached out to the team. She championed the ISCC within DIN, whose committee for the description and identification of documents (NA 009-00-09 AA) took up the proposal and brought it forward to ISO.

• The Content Blockchain Project won the Startup category of Germany's first Digital Publishing Award, presented under the patronage of the Federal Ministry for Economic Affairs and Energy.
• At the annual meeting of ISO/TC 46/SC 9 (Technical Committee 46, Information and documentation; Subcommittee 9, Identification and description) in Ottawa, the ISCC was accepted as a work item on the proposal of the German national body (DIN). A dedicated working group, ISO/TC 46/SC 9/WG 18, was established to develop it and held its first meeting on 29 October 2019, initially convened by Sabine Rüsch, who chaired that DIN committee.
• The ISCC Foundation was established as a non-profit Stichting in Leiden, Netherlands, in May 2019 to provide an independent, neutral home for the standard and its open-source implementations.

Throughout 2019 the team presented the ISCC at industry events across Europe, and the toolkit was extended with identifiers for audio and video content.

Standardization (2020-2023)¶

The years after ISO acceptance went into the detailed work of turning a working specification into an international standard, and into maturing the software.

• 2020: The ISCC was added to the ONIX for Books code lists (from Issue 50), the major metadata standard used across the book-publishing supply chain. Within ISO, the work item was confirmed as NP 24138.
• 2021: Titusz Pan re-architected the reference software from the original proof-of-concept into focused, maintainable libraries, most importantly iscc-core (the reference algorithms) and iscc-sdk (a high-level toolkit). WG 18 delivered a study report documenting use cases and adoption interest to SC 9.
• 2022-2023: The standard advanced through the formal ISO stages: Working Draft → Committee Draft (CD) → Draft International Standard (DIS). The iscc-core reference implementation was aligned to each draft, reaching v1.0.0 in early 2023. This work was supported in part by StandICT.eu fellowships.

ISO 24138:2024 (2024)¶

On 15 May 2024, ISO 24138:2024 - Information and documentation - International Standard Content Code (ISCC) was published as a first-edition International Standard by ISO/TC 46/SC 9. Titusz Pan served as the Principal Editor of the standard, authoring its normative text.

The standard defines the ISCC as a multi-component, similarity-preserving identifier for digital content, specifying its codec, header structure, and the algorithms for the Meta-, Content-, Data-, and Instance-Code units. The reference implementation, iscc-core, provides a conformant, open-source codec under a permissive license.

NISO, the secretariat of SC 9, introduced the standard to the wider identifier community shortly after publication.

Beyond the standard (2024 onward)¶

With ISO 24138 published, work shifted toward the standard's role in the broader content ecosystem:

• Soft binding: WG 18 began preparing a Technical Report on "soft binding" for information identification - re-associating provenance and metadata with content after files are re-encoded or stripped of embedded data. The work is coordinated with ISO efforts on content provenance.
• Provenance and authenticity: Just two days after publication, the ISCC was registered on the C2PA soft-binding algorithm list (17 May 2024), among the first algorithms admitted and the first based on content fingerprinting rather than digital watermarking. Within the C2PA / Content Credentials ecosystem the ISCC works as a soft binding, reconnecting content with its provenance after the embedded data has been stripped or re-encoded away. It is also listed among the asset-identifier standards in the IEC/ISO/ITU technical report on AI and multimedia authenticity (2025), alongside C2PA Content Credentials and JPEG Trust.
• Policy and rights management: As the European Union implements the AI Act's transparency and text-and-data-mining (TDM) provisions, rights-management organizations have pointed to the ISCC as a content-derived basis for machine-readable rights reservations. The International Federation of Reproduction Rights Organisations (IFRRO) named the ISCC in its 2026 response to the European Commission's consultation on TDM rights-reservation protocols, and the World Intellectual Property Organization (WIPO) had earlier featured it in a 2022 webinar on copyright in the digital environment.
• Science and bioimaging: Launched in November 2024, the BioCodes project brings the ISCC to bioimaging research, using it to verify data integrity, detect duplicates, and trace the provenance of scientific images across their lifecycle - from raw data through repositories to publication. Funded by the European Union through the OSCARS initiative (Horizon Europe grant 101129751), it brings together the ISCC Foundation (Titusz Pan), Leiden University (coordinated by Sylvia Le Dévédec), and German BioImaging (Josh Moore).
• Continued development: The ISCC Foundation and community continue to extend the framework with experimental units such as Semantic-Codes (meaning-based similarity) and tooling for notarization, registration, and discovery.

People and credits¶

The ISCC is the work of a community, but a few roles are central to its history:

• Titusz Pan - inventor of the ISCC, principal developer of its open-source reference implementation, Principal Editor of ISO 24138:2024, and Chairman of the ISCC Foundation
• Kira Lemke - director of the ISCC Foundation and convenor of ISO/TC 46/SC 9/WG 18 since May 2025
• Martin Etzrodt - director of the ISCC Foundation (since 2025) and a driving force behind the BioCodes project, which brings the ISCC to scientific and bioimaging data
• Sebastian Posth - evangelist and early adopter of the ISCC, convenor of ISO/TC 46/SC 9/WG 18 until May 2025
• Sabine Rüsch - first convenor of ISO/TC 46/SC 9/WG 18 (2019)
• Gregor Roschkowski - project manager at DIN who managed the ISCC standardization process from the German side, coordinating the national mirror committee for ISO/TC 46/SC 9/WG 18
• Julia Constanze Hahn - of Beuth Verlag / DIN (today DIN Media), who recognized the ISCC's potential and set its path to ISO standardization in motion through DIN
• Paul Jessop - long-standing contributor to ISO's media-identifier standards (ISRC, ISWC, ISNI, DOI). Initially critical of the ISCC, he became one of its advocates within ISO/TC 46/SC 9/WG 18 and advised on fingerprinting and soft bindings.

The ISCC Foundation's work has also been guided by an advisory board whose members contribute expertise across standards, libraries, rights management, publishing, and research:

• Roanie Levy - Licensing and Legal Advisor at the Copyright Clearance Center
• Todd Carpenter - Executive Director of NISO
• Philippe Rixhon - CEO of Valunode, active in EU copyright and AI policy
• Frank Schulleri - content licensing and media expert
• Lambert Heller - TIB, Leibniz Information Centre for Science and Technology
• Giacomo D'Angelo - CEO of StreetLib and Amlet
• Sebastian Posth - CEO of Liccium

These names are only a selection. The ISCC also owes much to the experts of ISO/TC 46/SC 9/WG 18, drawn from national bodies and organizations across many countries, to the wider open-source community that builds on and around the standard, and to the many others who have helped along the way.