There are now more than 1 billion OCLC Control Numbers and today OCLC formally announced they’re now in the public domain.
First, if you’re unaware of what OCLC Control Numbers here are two simple definitions from OCLC.
The OCLC Control Number is a unique, sequentially assigned number associated with a record in WorldCat. The number is included in a WorldCat record when the record is created. The OCLC Control Number enables successful implementation and use of many OCLC products and services, including WorldCat Local and WorldCat Navigator.
The OCN identifies the record, but is not part of the record itself. It is used in a variety of human and machine-readable processes, both on its own and in subsequent manipulations of catalog data.
Now in the Public Domain
Recently we recommended that OCLC declare OCLC Control Numbers (OCN) as dedicated to the public domain. We wanted to make it clear to the community of users that they could share and use the number for any purpose and without any restrictions. Making that declaration would be consistent with our application of an open license for our own releases of data for re-use and would end the needless elimination of the number from bibliographic datasets that are at the foundation of the library and community interactions.
We think this is important to do to counter act some practices based on misunderstandings that emerged from concerns about OCLC having an overly restrictive record use and re-use policy.
In the remainder of Michalko’s blog post, he discusses the misunderstandings and provides six basic examples of how OCNs are used by librarians and publishers.
Learn More About OCLC Control Numbers
- OCLC Control Number Info Page
- Additional Examples of How OCNs are Utilized
- How OCNs are Created
- OCNs in MARC Records
- OCLC WorldCat Data Use and Licensing Info Page
Note section on Use of the OCLC Control Number (OCN)
From the Licensing Info Page
Open Data Commons Attribution License (ODC-BY), which means you should: attribute your use of this database to us and OCLC, and; review the OCLC community norms for how we would like our institutions to be treated.