ISCC Terms¶

http://schema.org/name

The name of the item.

Comment: The title or name of the intangible creation manifested by the identified digital content. Used as input for ISCC Meta-Code generation.

Embedding: Use Iptc.Application2.Headline and Xmp.photoshop.Headline for image embedding

Standard: ISO 24138:2024

Status: stable

http://schema.org/disambiguatingDescription

A sub property of description. A short description of the item used to disambiguate from other, similar items. Information from other properties (in particular, name) may be necessary for the description to be useful for disambiguation.

Comment: Description of the digital content identified by the ISCC. Used as input for ISCC Meta-Code generation. Any user presentable text string (including Markdown text) indicative of the identity of the referent may be used.

Embedding: Use Exif.Image.ImageDescription, Iptc.Application2.Caption and Xmp.dc.description for image embedding.

Standard: ISO 24138:2024

Status: stable

http://schema.org/creator

The creator/author of this CreativeWork. This is the same as the Author property for CreativeWork.

Comment: An entity primarily responsible for making the resource.

Embedding: Use Exif.Image.Artist, Iptc.Application2.Byline and Xmp.dc.creator for emedding this field into image metadata.

Status: draft

http://schema.org/license

A license document that applies to this content, typically indicated by URL.

Comment: URI of license for the identified digital content.

Embedding: Use Xmp.xmpRights.WebStatement for embedding as image metadata.

Status: stable

http://schema.org/acquireLicensePage

Indicates a page documenting how licenses can be purchased or otherwise acquired, for the current item.

Comment: This field must contain a valid URL referring to a page showing information about how one can acquire a license for the item. This may be a page of a web shop or NFT marketplace ready for providing a license.

Embedding: Use Xmp.plus.Licensor[1]/plus:LicensorURL for embedding in images.

Status: stable

http://schema.org/creditText

Text that can be used to credit person(s) and/or organization(s) associated with a published Creative Work.

Comment: A line of text that you expect users of the image (such as Google Images) to display alongside the image.

Embedding: Use Iptc.Application2.Credit and Xmp.photoshop.Credit for metadata embedding.

Status: draft

http://schema.org/copyrightNotice

Text of a notice appropriate for describing the copyright aspects of this Creative Work, ideally indicating the owner of the copyright for the Work.

Comment: Contains any necessary copyright notice and should identify the current owner of the copyright of this work with associated intellectual property rights.

Embedding: Use Exif.Image.Copyright, Iptc.Application2.Copyright and Xmp.dc.rights for embedding.

Status: draft

http://schema.org/image

An image of the item. This can be a URL or a fully described ImageObject.

Comment: URI for a user-presentable image that serves as a preview of the digital content. The URI may be a Data-URL RFC2397. If ISCC metadata is used as NFT metadata according to ERC-721 or ERC-1155 the URI should reference the actual digital content represented by the NFT.

Status: draft

http://schema.org/identifier

The identifier property represents any kind of identifier for any kind of Thing, such as ISBNs, GTIN codes, UUIDs etc. Schema.org provides dedicated properties for representing many of these, either as textual strings or as URL (URI) links. See background notes for more details.

Comment: Other identifier(s) referencing the work, product or other abstraction of which the referenced digital content is a full or partial manifestation. Accepts a bare string, a typed Identifier object, or a list mixing both forms.

Standard: ISO 24138:2024

Status: draft

http://schema.org/contentUrl

Actual bytes of the media object, for example the image file or video file.

Comment: URI of the digital content that was used to create this ISCC.

Status: draft

http://schema.org/keywords

Keywords or tags used to describe this content. Multiple entries in a keywords list are typically delimited by commas.

Comment: Keywords or tags used to describe this content. Either a list of keywords or a string with comma separated keywords.

Standard: ISO 24138:2024

Status: stable

http://schema.org/additionalType

An additional type for the item, typically used for adding more specific types from external vocabularies in microdata syntax. This is a relationship between something and a class that the thing is in.

Comment: The form or kind of content identified, using a Schema.org CreativeWork subtype. While @type provides a coarse modality classification (text, image, audio, video) and mode/mediatype describe technical aspects, form captures what the content is — a book, scholarly article, presentation, report, photograph, etc.

Status: draft

http://schema.org/version

The version of the digital content identified by the ISCC.

Comment: The version of the CreativeWork embodied by a specified resource.

Status: draft

http://schema.org/dateCreated

The date on which the CreativeWork was created or the item was added to a DataFeed.

Comment: Datetime the ISCC was created for the item.

http://schema.org/fileSize

Size of the application / package (e.g. 18MB). In the absence of a unit (MB, KB etc.), KB will be assumed.

Comment: File size of media asset in number of bytes.

Standard: ISO 24138:2024

Status: stable

http://schema.org/encodingFormat

Media type typically expressed using a MIME format (see IANA site and MDN reference) e.g. application/zip for a SoftwareApplication binary, audio/mpeg for .mp3 etc.). In cases where a CreativeWork has several media type representations, encoding can be used to indicate each MediaObject alongside particular encodingFormat information. Unregistered or niche encoding and file formats can be indicated instead via the most appropriate URL, e.g. defining Web page or a Wikipedia/Wikidata entry.

Comment: An IANA Media Type (MIME type)

Standard: ISO 24138:2024

Status: stable

http://schema.org/duration

The duration of the item (movie, audio recording, event, etc.) in ISO 8601 date format.

Comment: Duration of audio-visual media in seconds.

Standard: ISO 24138:2024

Status: stable

http://schema.org/numberOfPages

The number of pages in the book.

Comment: Number of pages (for paged documents only)

Status: draft

http://schema.org/inLanguage

The language of the content or performance or used in an action. Please use one of the language codes from the IETF BCP 47 standard. See also availableLanguage.

Comment: Language(s) of content BCP 47.

Standard: ISO 24138:2024

Status: stable

http://schema.org/thumbnailUrl

A thumbnail image relevant to the Thing.

Comment: URI of an autogenerated user-presentable thumbnail-image that serves as a preview of the digital content. The URI may be a Data-URL RFC2397.

Standard: ISO 24138:2024

Status: stable

https://www.w3.org/2018/credentials#VerifiableCredential

A credential is a set of one or more claims made by an issuer. A verifiable credential is a tamper-evident credential that has authorship that can be cryptographically verified. Verifiable credentials can be used to build verifiable presentations, which can also be cryptographically verified. The claims in a credential can be about different subjects.

Comment: One or more Verifiable Credentials or one or more URIs pointing to one or more VCs. A reader of ISCC metadata must interpret the value according to the following rules

• If the value is a JSON string interpret it as an URI. The expectation is that the URI dereferences to a response with Content-type application/json where the data is a VC or an array of VCs.
• If the value is a JSON object interpret it as a VC according to the Verifiable Credentials JSON Schema.
• If the value is an array and an item in the array is a JSON object interpret it as a VC.
• If the value is an array and an items is a string interpret the item as an URI that dereferences to VC(s)
• Credentials should only be taken into account if the credentialSubject matches with the declarer (e.g. did:pkh representation of the declarers address).

Status: draft

http://purl.org/iscc/terms/#iscc

An ISCC-CODE in canonical representation. A valid ISCC Metadata object should include at least one of the iscc, iscc_id, or iscc_code fields.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#meta

Subject, industry, or use-case specific metadata encoded as Data-URL.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#media_id

Vendor specific (internal) identifier for the source media file.

Status: draft

http://purl.org/iscc/terms/#iscc_id

The ISCC-ID of the digital content in canonical representation. A valid ISCC Metadata object should include at least one of the iscc, iscc_id, or iscc_code fields.

Status: stable

http://purl.org/iscc/terms/#iscc

A composite ISCC-CODE in canonical representation. Explicit alternative to the more compact iscc field. A valid ISCC Metadata object should include at least one of the iscc, iscc_id, or iscc_code fields.

Status: stable

http://purl.org/iscc/terms/#previous

ISCC of the preceding version of this item.

Status: draft

http://purl.org/iscc/terms/#genai

Machine-readable generative AI disclosure signals for content transparency. Omitted fields indicate that the disclosure status has not been determined.

Status: draft

http://purl.org/iscc/terms/#mode

The perceptual mode used to create the ISCC-CODE.

Status: stable

http://purl.org/iscc/terms/#filename

Filename of the referenced digital content (automatically used as fallback if the name field was not specified for ISCC processing)

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#datasize

Size of the data processed for ISCC generation in number of bytes. Use this field when the ISCC is computed over data that is not a standalone file, such as an individual plane within a bioimage, a scene within a multi-scene container, or a data stream extracted from a composite format.

Status: draft

http://purl.org/iscc/terms/#fps

Frames per second of video assets.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#width

Width of visual media in number of pixels.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#height

Height of visual media in number of pixels.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#characters

Number of text characters (code points after Unicode normalization)

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#parts

Indicates items that are part of this item via Content-Codes (inverse-property belongs).

Status: draft

http://purl.org/iscc/terms/#part_of

Indicates that this item is part of other items via their Content-Code.

Status: draft

http://purl.org/iscc/terms/#features

Granular features of the digital content.

Status: draft

http://purl.org/iscc/terms/#units

Individual ISCC-UNITs that make up a composite ISCC-CODE.

Status: draft

http://purl.org/iscc/terms/#generator

Name and version of the software that generated the ISCC

Status: stable

http://purl.org/iscc/terms/#text

Extracted plaintext of the digital content.

Status: draft

http://purl.org/iscc/terms/#external_url

This is the URL that will appear below the asset's image on some NFT Marketplaces and will allow users to leave the site and view the item on your site. Supports URI template (iscc-id).

Status: draft

http://purl.org/iscc/terms/#animation_url

A URL to a multi-media attachment for the item.

Status: draft

http://purl.org/iscc/terms/#properties

Arbitrary properties. Values may be strings, numbers, object or arrays. Properties defined here may show up on NFT marketplaces. See ERC-1155

Status: draft

http://purl.org/iscc/terms/#attributes

Similar to properties but as an array of objects. These attributes will show up on some NFT marketplaces.

Status: draft

http://purl.org/iscc/terms/#nft

A unique URI for a non-fungible token of the identified content. The URI must contain references to the blockchain, smart-contract and token. The recommended schemes are CAIP-22 and CAIP-29.

Status: draft

http://purl.org/iscc/terms/#tophash

A Multihash of the concatenation (binding) of metahash and datahash (default blake3).

Standard: ISO 24138:2024

Status: draft

http://purl.org/iscc/terms/#metahash

A Multiformats multihash or IPFS CIDv1 of the supplied metadata. The hash is created from name and description fields or meta if supplied.

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#datahash

A Multihash of the digital content (default blake3).

Standard: ISO 24138:2024

Status: stable

http://purl.org/iscc/terms/#nonce

Cryptographic nonce for replay protection. A 128-bit random value encoded as lowercase hexadecimal.

Status: stable

http://purl.org/iscc/terms/#signature

Cryptographic signature over ISCC metadata, conforming to the iscc-crypto signing protocol. Uses EdDSA (Ed25519) with JCS canonicalization.

Status: stable

http://purl.org/iscc/terms/#original

The signee of the declaring transaction claims to be the original creator of the work manifested by the identified digital content.

Status: stable

http://purl.org/iscc/terms/#redirect

URL to which an ISCC resolver should redirect the ISCC-ID. Supports URI template (iscc-id)

Status: stable

http://purl.org/iscc/terms/#chain

The blockchain on which an ISCC-CODE is declared.

Status: draft

http://purl.org/iscc/terms/#wallet

The wallet-address that signs an ISCC declaration.

Status: draft

http://purl.org/iscc/terms/#verifications

A list of self-verifications. Self-verifications are public URLs under the account/authority of the signee. The verification URL must respond to a GET request with text that contains a multihash of the ISCC declaration signees wallet address in the format of verify:<multihash-of-wallet-address>:verify.

Status: draft

http://schema.org/isbn

International Standard Book Number in 13-digit format, without spaces or hyphens.

http://purl.org/iscc/terms/#productform

Product form code indicating the medium and format of the publication (ONIX codelist 150).

http://schema.org/name

The title of the publication.

http://schema.org/inLanguage

ISO 639-2/B three-letter language code.

http://schema.org/publisherImprint

The brand name under which the publication is published.

http://schema.org/publisher

The person or organization that owns the imprint at the date of publication.

http://schema.org/countryOfOrigin

Country of publication in accordance with ISO 3166-1 alpha-2 country codes.

http://schema.org/datePublished

The date of first publication under this ISBN in ISO 8601 basic format (YYYYMMDD).

http://schema.org/isrcCode

The International Standard Recording Code assigned to this recording.

http://schema.org/byArtist

The name of the featured artist or band.

http://schema.org/name

The title of the recording.

http://schema.org/alternativeHeadline

Additional information about the recording, such as 'live' or 'remastered'.

http://schema.org/duration

The elapsed playing time of the recording in seconds.

http://purl.org/ontology/bibo/doi

Digital Object Identifier of the work, lowercased, in bare prefix form (without the https://doi.org/ resolver prefix).

http://schema.org/additionalType

The kind of research output as a readable token. Tokens follow the DataCite resource-type vocabulary and are populated from the Crossref/DataCite work type (for example, journal-article maps to JournalArticle). Each token is mapped to a resolvable schema.org or FaBiO class IRI in the JSON-LD context (see x-iscc-enum-context). This is the work-kind axis; version_type is the orthogonal version-stage axis.

http://schema.org/datePublished

Year of publication. Crossref guarantees year-level precision only; using an integer avoids the false precision of a full date.

http://purl.org/iscc/terms/#version_type

Manifestation version using the NISO JAV (RP-8-2008) vocabulary. Publisher-specific version taxonomies are mapped into these values. Lets a Version-of-Record and an Accepted-Manuscript of the same work produce different Meta-Codes while a shared work-level doi links them.

http://prismstandard.org/namespaces/basic/2.0/publicationName

Title of the serial or collection the work is part of (journal, proceedings, book). Not guaranteed for standalone works.

http://schema.org/issn

ISSN of the container serial. Only present for serial publications.

http://purl.org/iscc/terms/#TDM

Machine-readable TDM rights signals conformant with W3C TDMRep, providing content-addressed delivery of tdm-reservation and tdm-policy properties via ISCC. Designed for content identification and discovery where identity, provenance, and trust context complement the reservation signal.

http://www.w3.org/ns/tdmrep#reservation

Blanket TDM reservation flag, semantically equivalent to W3C TDMRep tdm-reservation. 1 = rights reserved (EU DSM Art. 4 opt-out), 0 = not reserved, absent = undeclared.

Status: stable

http://www.w3.org/ns/tdmrep#policy

URL of a TDM Policy document (typically a JSON-LD ODRL Offer profiling TDMRep). Semantically equivalent to W3C TDMRep tdm-policy.

http://purl.org/iscc/terms/#GenAI

Machine-readable generative AI disclosure signals for content transparency. Designed for AI providers to declare the level of AI involvement in content creation, supporting compliance with transparency regulations (e.g., EU AI Act Art. 50) and enabling end users to verify AI-generated content. These signals are designed for use within content identification and discovery protocols that provide additional identity, provenance, and trust context.

http://purl.org/iscc/terms/#involvement

Level of generative AI involvement in content creation. 'human' indicates content created purely by human effort without generative AI. 'ai_assisted' indicates content created by human effort with support from generative AI. 'human_supervised' indicates content created by generative AI but supervised or reviewed by humans. 'ai_generated' indicates content created by generative AI without human supervision.

http://purl.org/iscc/terms/#ai_system

Name or identifier of the generative AI system used for content creation. Aligns with IPTC Photo Metadata 2025.1 'AI System Used' property.

http://purl.org/iscc/terms/#digital_source_type

IPTC Digital Source Type URI for granular content source classification. This optional field bridges to the IPTC controlled vocabulary, an external evolving standard that offers finer-grained source type distinctions than the 'involvement' field. Also used by C2PA Content Credentials. See https://cv.iptc.org/newscodes/digitalsourcetype/

http://purl.org/iscc/terms/#Identifiers

Set of typed external identifiers served for an asset identified by an ISCC.

http://schema.org/propertyID

Lowercase token naming the identifier namespace, such as doi, isrc, iswc, isbn, issn, ror, or orcid.

Status: draft

http://schema.org/value

Identifier value within the declared scheme, normalized by the producer according to the scheme's conventions.

Status: draft

http://purl.org/iscc/terms/#scope

Optional lowercase token naming the level the identifier applies to, such as work, series, manifestation, asset, organization, or person.

Status: draft

http://purl.org/iscc/terms/#primary

Preferred identifier flag within the same scope. True means preferred; false is equivalent to omission and is normalized away by the model construction path.

Status: draft

http://purl.org/iscc/terms/#datahash

A blake3 multihash of the digital content, hex-encoded with the 1e20 multihash prefix (blake3, 32-byte digest). Binds the declaration to the exact content bytes.

http://purl.org/iscc/terms/#nonce

Cryptographic nonce for replay protection. A 128-bit random value encoded as lowercase hexadecimal.

http://purl.org/iscc/terms/#timestamp

RFC 3339 timestamp of declaration creation in UTC with millisecond precision. Optional on submission - an ISCC-HUB assigns the authoritative timestamp on receipt.

http://purl.org/iscc/terms/#signature

Cryptographic signature over the IsccNote, conforming to the iscc-crypto signing protocol. Uses EdDSA (Ed25519) with JCS canonicalization.

http://purl.org/iscc/terms/#units

The individual full-length ISCC-UNITs that compose the declared ISCC-CODE, enabling similarity matching against the declaration. One to four 256-bit ISCC-UNITs.

http://purl.org/iscc/terms/#metahash

A blake3 multihash of the seed metadata, hex-encoded with the 1e20 multihash prefix (blake3, 32-byte digest). Same format as datahash.

http://purl.org/iscc/terms/#gateway

An HTTP(S) URL or RFC 6570 URI template of a gateway that serves metadata for the declared ISCC. Used by ISCC resolvers to discover content metadata.