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Guidelines for experts

Find authorizations, basic principles, and other guidelines for the Expert Community.


OCLC's Expert Community provides Connexion users who have a Full Level authorization or higher more flexibility in making changes to WorldCat bibliographic records. Maintenance of WorldCat will be shared more equally between OCLC staff and member libraries. The additional capabilities provided are a powerful expansion of those that have been available especially through Database Enrichment since 1991.

The Expert Community Experiment resulted in more corrections and additions to WorldCat bibliographic records and more timely actions to correct record problems. The Experiment was inspired by longstanding requests from members of the OCLC cooperative to be able to do more—and more immediate—upgrading of bibliographic records in WorldCat. The Experiment allowed us to test a "social cataloging" model involving the existing community of cataloging experts who have built WorldCat record-by-record over the past nearly four decades. Interest in such a model grew especially with the launch of WorldCat Local and with the popularity of such other socially cooperative ventures as Wikipedia. We hope the continuation of the Expert Community will continue to result in more timely actions to correct records within WorldCat on the part of OCLC members.


Any Full-Level authorization or higher (including CONSER Regular, CONSER National, Regular Enhance, National Level Enhance, NACO Regular, NACO National, and Agent) have the functionality to participate in the Expert Community. There is no need to apply for any special authorizations. All existing Enhance, CONSER, and NACO authorizations will continue to work as they always have but will also have all of the additional capabilities allowed within the Expert Community.

Basic principles of the Expert Community

The overriding principle of the Expert Community is: "First, do no harm." Please use the same care in editing an existing WorldCat record as you would use in creating a new record.

  • NEVER remove correct and accurate information from a WorldCat record (such as classification numbers or subject headings) simply because your institution does not find it useful.
  • NEVER change the basic nature of a WorldCat bibliographic record into something different.
  • AVOID including local data or local practices in WorldCat bibliographic record.
  • Be cautious about changing bibliographic records with a different Language of Cataloging (identified in field 040 subfield ‡b). Bibliographic Formats and Standards, Section 2.6: Language of Cataloging, has details on working with these records.

A second overriding principle is: "If in doubt, DON'T."

  • Do not replace a record solely to change an element that is a matter of cataloger's judgment.
  • Consider data within the context of the whole record, rather than in isolation. If you can reasonably resolve contradictory information within a record, please do so, but try not to jump to conclusions.
  • Please behave responsibly concerning each other's records. Remember that each library that replaces a record input by another library appears, by virtue of the 040 field, to have some responsibility for the content of that record.

Bibliographic records included and excluded

The Expert Community allows members of the OCLC cooperative with Full-Level cataloging authorizations and higher to make additions and changes to almost all fields in almost all records. There are a few relatively limited exceptions and a few additional details:

  • PCC records—both BIBCO and CONSER records—are EXCLUDED. These records are identified by one or more of the following field 042 authentication codes: isds/c, lc, lcd, msc, nlc, nsdp, nst, pcc.
  • LC records that are NOT coded as PCC records are INCLUDED.
  • CIP records (Encoding Level "8") that are coded as PCC can be changed, but the Encoding Level must remain at "8."
  • Institutional Records (IRs) are EXCLUDED.
  • Records in the Hand Press Books database are EXCLUDED.
  • Records with Encoding Level "E" are EXCLUDED.

Bibliographic data that cannot be changed

Most fields within an eligible WorldCat bibliographic record can be changed, with the following EXCEPTIONS:

  • System-supplied data (040 subfield ‡c, Entered).
  • Fields 019, 029, 066, 850, and 938.
  • Field 042 (except that, when upgrading an Encoding Level "3" record, you can remove field 042 with code "dc").

Note also that WorldCat bibliographic records CANNOT be deleted from WorldCat by Expert Community participants.


For users of the Connexion client, you can replace a record without locking it first and you can do replace transactions in batches if you prefer.

Some important points about the lock and replace process:

  • At least one field retained in the WorldCat record MUST be edited before you can do a replace.
  • Your OCLC symbol automatically appears in 040 subfield ‡d after replace.
  • "Replaced" date changes.
  • A Replace transaction DOES NOT set your holdings.
  • OCLC requests that work on locked records be completed as expeditiously as possible. This affords other users access to your improved record right away and allows OCLC automated database quality software to work more effectively. Locked records cannot be processed by Duplicate Detection and Resolution software, automated authority control software, or database scans.
  • Please see Connexion documentation for your WorldCat interface for details of record expiration in the save file.

You may want to re-familiarize yourself with the sorts of local information that can be present in a record at the point of replace but that is not added to the WorldCat record. See the section Replacing Records with Local Information in Bibliographic Formats and Standards.

Share information about the Expert Community

OCLC hopes that members of the cooperative participating in the Expert Community will share their experiences on the OCLC-CAT discussion list (OCLC-CAT@OCLC.ORG). In addition, questions may be addressed to ASKQC@OCLC.ORG.