OCLC and linked data

Resource discoverability through connections

Research habits have changed. It’s no longer enough for libraries to simply maintain information resources for users to access. They now have to make the information visible to seekers where they begin their research. WorldCat provides libraries with an opportunity to display their holdings on websites beyond library catalogs in a format that search engines, citation management systems, campus platforms, research portals, and other information websites can read and repurpose.

Chew Chiat Naun

“OCLC is well placed...”

“As a major data hub, OCLC is well placed to develop linked data services for the library community.” 

Chew Chiat Naun
Head of Metadata Creation
Harvard Library
Cambridge, Massachusetts, United States

A significant step toward the future of library metadata

We continue to lead the global library metadata community in a way that no other organization can. With the support of the Mellon Foundation and our advisory group members, we’ve released 150 million WorldCat Entities containing descriptions of creative works and persons, which form the foundation of our shared entity management infrastructure.

Logo: WorldCat Entities

Anyone can explore this data through our publicly available website, entities.oclc.org. Library metadata specialists can begin using these entity URIs in their data today to start making connections that empower discovery and research.

WorldCat Entities form the initial foundation of our shared entity management infrastructure, which will allow libraries, OCLC, and other stakeholders to jointly curate linked data. We're now partnering with key libraries to help us refine and enhance an entities management tool—OCLC Meridian—and APIs, to give libraries what they need to fully incorporate linked data into their workflows, empowering discovery through connections that answer questions researchers haven't yet thought to ask.

Skip Prichard

“...stewards of library data”

“OCLC has been at the forefront of linked data research for years, using our expertise as stewards of library data to guide us through development of prototypes, pilot programs, and partnerships to inform our work. The release of WorldCat Entities helps make linked data work for libraries, and our look-up site allows anyone to explore WorldCat Entities and prepare for the future.”

Skip Prichard
President and CEO
Dublin, Ohio, United States

Creating library linked data with Wikibase

OCLC's ten-month Project Passage pilot let librarians from 16 US institutions create linked data describing library and archival resources in a Wikibase sandbox. The librarians worked with OCLC on a framework for reconciling, evaluating, and managing traditional metadata as linked data entities and relationships. This opportunity revealed the potential of linked data in library catalogs as well as the gaps to address before fully adopting machine-readable semantic data can be fully adopted.


To learn more:

kalan Knudson Davis

“Monumental development...”

“[We are] re-envisioning the very fabric of the Bibliographic Universe. Linked data, as a monumental development with implications for the future of library resource discoverability, has a lot riding on it. We know it. OCLC knows it. Your library vendors know it.”

kalan Knudson Davis
Special Collections Metadata Librarian
University of Minnesota
Minneapolis, Minnesota, United States

OCLC Research CONTENTdm linked data pilot

Connecting people with unique digital resources

Our OCLC Research report Transforming metadata into linked data to improve digital collection discoverability shares findings from our CONTENTdm linked data pilot project. We partnered with institutions that manage their digital collections with OCLC’s CONTENTdm service to investigate methods for—and the feasibility of—transforming metadata into linked data to improve the discoverability and management of digitized cultural materials and their descriptions. The OCLC Research webinar, "On the way to library linked data," offers further thoughts on this work.

Download the report

Improving the interoperability of digital materials

As a founding member of IIIF (the International Image Interoperability Framework), OCLC is leading the effort to create new standards for sharing structural metadata about digital images, audio, and video with the library community.

Learn more about support for IIIF in CONTENTdm

Illustration: Linked data collaboration

Linked data as a cooperative effort

OCLC works closely with other organizations, such as the Library of Congress, to ensure that library data are included on the web. We believe that linked data representations will eventually replace MARC. By cooperating with other data standards groups and making WorldCat data available to them, we both enhance the value of WorldCat and ensure that libraries have a voice in the future of information management.


OCLC remains committed to working with the Library of Congress and the library community to help finalize the BIBFRAME standard, an evolving model to share and connect bibliographic data. As multiple variants continue to evolve, we will continue to evaluate BIBFRAME data to help inform our linked data planning activities with a goal to allow all OCLC members to continue to register their collections in WorldCat.

Program for Cooperative Cataloging

OCLC is actively engaged with libraries within the Program for Cooperative Cataloging (PCC) to explore standards, policies, and best practices as library metadata transitions from MARC to linked data. OCLC participates in several committees and tasks forces including the Standard Committee on Standards, the Standard Committee on Training, and the Linked Data Advisory Group.

Upcoming & on-demand events

04 October 2022

Linked data - maar hoé dan?!

Linked data is een ‘hot topic’, en het ziet ernaar uit dat iedereen moet meedoen. Gelukkig is er steeds meer informatie over wat linked data is.

13 July 2022

Transforming Metadata

Library metadata is transforming. Join us as a panel of experts explores the changes taking place in a number of areas, including the transition to linked data and identifiers, the description of inside-out and facilitated collections, the evolution of metadata as a service, as well as resulting staffing requirements.

View more linked data events