NISONISO Z39.105-2023, commonly known as Content Profile/Linked Document (CP/LD), is a technical standard published in December 2023 that brings semantic web principles to scholarly publishing. By combining HTML and JSON-LD, it provides a framework for creating self-describing, machine-actionable documents that can be readily discovered, reused, and interchanged across scholarly communication systems.
Background
The standard emerged from the NISO Content Profile/Linked Document Working Group, which recognized a growing need in the scholarly publishing ecosystem for a format that could natively express semantic relationships between content and data elements. While many existing standards address parts of this problem -- metadata schemas for discovery, XML formats for article structure, RDF for semantic data -- CP/LD was designed to unify these capabilities into a single, web-native format built on widely supported technologies.
The standard was approved as an American National Standard (ANSI) and published by NISO (National Information Standards Organization) with the designation Z39.105-2023 on December 12, 2023. NISO is an ANSI-accredited standards development organization founded in 1939 as the Z39 Committee, developing standards for publishing, bibliographic, and library applications. NISO represents US interests to the International Organization for Standardization's Technical Committee 46 (Information and Documentation). Unlike most ANSI standards, all NISO standards and best practices are freely available from its website.
Purpose & Scope
CP/LD addresses the challenge of making scholarly research information truly interoperable and machine-actionable. The standard defines two key concepts:
- Linked Documents: Documents that conform to a minimal set of rules ensuring they are self-describing and semantically rich, built on standard HTML with embedded JSON-LD.
- Content Profiles: More detailed rule sets that extend and refine the base Linked Document specification for particular use cases, communities, or content types.
The specification does not aim to replace existing models used for journal articles, books, datasets, or metadata schemas. Instead, CP/LD enables content from these diverse formats to be transformed as needed into a common, standards-based representation. This allows the combination of arbitrary portions of content, data, semantics, and other resources from separate sources into a unified format optimized for interchange, search, and display.
Key Technical Features
CP/LD builds on two foundational web technologies:
- HTML: The universal document format of the web, ensuring broad accessibility and rendering capability.
- JSON-LD: A lightweight Linked Data format that embeds structured, semantic data within HTML documents.
By leveraging these widely adopted standards, CP/LD avoids requiring specialized tooling or processing pipelines. Any system that can parse HTML and JSON-LD can work with CP/LD documents at a basic level.
Governance & Maintenance
The standard is maintained by the National Information Standards Organization (NISO), which serves the library, publishing, and information services communities. NISO standards follow a consensus-based development process involving public comment periods and ballot voting by NISO voting members. The CP/LD Working Group continues to oversee the standard's development and adoption. NISO is designated by ANSI to represent US interests to ISO TC 46 and ISO/IEC JTC 1/SC 34 (Document description and processing languages).
Potential Applications
Given its focus on scholarly publishing, CP/LD is relevant to:
- Academic publishers seeking machine-actionable article formats
- Repository platforms that aggregate research from multiple sources
- Research data management systems requiring semantic interoperability
- Discovery services that need rich, structured content for indexing
- Preservation systems that benefit from self-describing documents
Related Standards
CP/LD intersects with several existing standards and technologies in the scholarly communication space, including JATS (Journal Article Tag Suite, also a NISO standard as Z39.96), Schema.org for web-embedded metadata, and various RDF-based vocabularies for scholarly data.