OCLC Declare OCLC Control Numbers Public Domain by Richard Wallis.
From the post:
I signalled that OCLC were looking at this, in my session (Linked Data Progress), at IFLA in Singapore a few weeks ago. I am now pleased to say that the wording I was hinting at has now appeared on the relevant pages of the OCLC web site:
Use of the OCLC Control Number (OCN)
OCLC considers the OCLC Control Number (OCN) to be an important data element, separate from the rest of the data included in bibliographic records. 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. OCLC makes no copyright claims in individual bibliographic elements nor does it make any intellectual property claims to the OCLC Control Number. Therefore, the OCN can be treated as if it is in the public domain and can be included in any data exposure mechanism or activity as public domain data. OCLC, in fact, encourages these uses as they provide the opportunity for libraries to make useful connections between different bibliographic systems and services, as well as to information in other domains.
The announcement of this confirmation/clarification of the status of OCNs was made yesterday by my colleague Jim Michalko on the Hanging Together blog.
See: OCLC Control Number if you are interested in the details of OCNs (which are interesting in and of themselves).
Unlike the Perma.cc links, OCNs are not tied to any particular network protocol.
However you deliver an OCN, by postcard, phone or network query, an information system can respond with the information that corresponds to that OCN.
No one can promise you “forever,” but not tying identifiers to ephemeral network protocols is one way to get closer to “forever.”