While the OCLC number is the Alliance’s primary record identifier, not all other systems use the OCLC number as the primary record identifier. The addition of ISBNs to WorldCat records will help identify and match library resources in other systems.
When Alliance catalogers find Network Zone records that lack ISBNs, the ISBNs should be added to the WorldCat record when feasible.
Only add ISBNs to WorldCat with the piece in hand or from an acceptable surrogate (e.g., a photocopy, preservation scan, or photo of the item; another item in the multipart monograph set). Do not use other sources of information.
Generally, add qualifiers to ISBNs to tell what they are for.
020 $a 0435916602 $q (cased)
020 $a 0435916610 $q (paperback)
Add ISBNs for the individual volumes in a multipart monograph. (You may also need to update other elements in the record, such as contents notes.) Also include the set ISBN if it is on the piece. For examples, see OCLC’s guidelines on the 020 field.
Add ISBNs for hardback or paperback to a WorldCat record for print when the hardback and paperback are cataloged on the same record. Refer to OCLC Bibliographic Formats and Standards “When to input a new record” for guidance on making this determination.
When transcribing ISBNs found on the piece, use 020 $z for e-ISBNs added to a bib record for print, and for print ISBNs added to a bib record for electronic. (This is in accordance with the LC-PCC policy statement for RDA 22.214.171.124. and with the Provider-Neutral E-Resource MARC Record Guide.)
In general, do not delete ISBNs from WorldCat records.
- If an 020 has been canceled, it may be moved to a subfield $z.
- If an 020 is completely incorrect, it may be removed from the record.
- When in doubt, report the incorrect/canceled ISBN to OCLC.
Refer to OCLC Bibliographic Formats and Standards 020 International Standard Book Number for more information.
Written by: Collaborative Technical Services Team, revised by Cataloging Standing Group
Approved by: Shared Content and Technical Services Team on 8/17/21
Last updated: 8/17/2021
Nature of last update: Changed from policy to best practice, revised.