When symbol expansion is implemented, 4-character holding library codes will no longer be unique across the entire system. They will be unique only in relation to the OCLC institution symbol in tag 994. Currently, most libraries and systems can safely ignore or delete tag 994 during processing. It has no meaning until symbol expansion is implemented with the exception of Z39.50 Cataloging. An announcement to Z39.50 Cataloging users is forthcoming.
Implementation is planned for the distant future.
They do not appear in records viewed in the OCLC Cataloging service online. This is not as simple as it seems. Tag 994 cannot be entered into a record and displayed.