Technical Bulletin 253
ISBN and OCLC Number Changes

September 2006

About Technical Bulletin 253

Route to

Route this document to cataloging, acquisitions, reference, and system staff.

Why read this?

To learn about how OCLC is implementing the expansion of the ISBN and OCLC control number.

Installation of changes

November 12, 2006

Questions

Contact your OCLC regional service provider for support. Contact the user training development manager at OCLC if you are an independent institution.

User Support

Customer Support hours at OCLC: 7:00 am—9:00 pm US Eastern time, Monday through Friday; 8:00 am—8:00 pm US Eastern time, Saturday. Saturday support is for telecommunications and hardware only. USA and Canada 1-800-848-5800; Mexico 95-800-848-5800; International and local (Central Ohio) 1-614-793-8682. Contact OCLC support.

Manuals affected

Bibliographic Formats and Standards, Holdings Formats and Standards, OCLC MARC Records

1 ISBN Changes

Expansion of ISBN to 13 digits

The International Standard Book Number (ISBN) is currently ten digits. Starting on January 1, 2007, the ISBN will be thirteen digits. Some publishers have already switched to the new, longer numbers. After January 1, 2007, they all must use them.

Currently, OCLC puts thirteen-digit ISBNs in field 024 (if they are found in field 020, OCLC moves them to field 024).

After November 12, 2006, OCLC will move all existing thirteen-digit ISBNs to field 020. For details, see section 2, OCLC Implementation of ISBN Changes.

Bookland EAN

The thirteen-digit ISBN is identical to the Bookland EAN. The International Article Number (EAN) is a thirteen-digit number assigned to all products. The Bookland EAN is the EAN assigned to books.

(The EAN originally stood for European Article Number. It now stands for International Article Number, but the acronym remains EAN.)

Bookland EAN prefixes

The Bookland EAN currently has a prefix of "978." However, the supply of "978" numbers is running out. When there are none left, the new prefix for Bookland EANs will be "979."

Thirteen-digit ISBN prefixes

Because the thirteen-digit ISBN is identical to the Bookland EAN, it has the "978" prefix. When numbers with "978" prefixes are exhausted, ISBNs will have the "979" prefix.

Converting ISBNs

Because some publishers are switching to thirteen-digit ISBNs before January 2007, there may be the need to convert ISBNs from one format to another. The following conversions are possible:

  • Ten-digit ISBN to thirteen-digit ISBN
  • Thirteen-digit ISBN with the "978" prefix to ten-digit ISBN

Note: Thirteen-digit ISBNs with the "979" prefix cannot be converted to ten-digit ISBNs because they have no ten-digit equivalent.

More information

For more informaton, see the links below.

2 OCLC Implementation of ISBN Changes

Field 020

The new thirteen-digit ISBN goes in subfield ‡a. There is no other change to field 020.

OCLC will store all ISBNs in field 020, as below:

  • Ten-digit ISBNs will be stored as ten-digit and thirteen-digit ISBNs
  • Thirteen-digit ISBNs will be stored as thirteen-digit ISBNs
  • Thirteen-digit ISBNs with the "978" prefix will also be stored as ten-digit ISBNs

Although this implementation may cause redundancy, it ensures that all ISBNs are available for indexing, searching, and linking. For example, a book originally published with a ten-digit ISBN might be reprinted with a thirteen-digit ISBN; searching for either number would retrieve it.

ISBNs in field 024

Requiring that thirteen-digit ISBNs be put in field 024 was a temporary practice until OCLC system changes made possible putting the ISBN in field 020. After November 12, 2006, you must put all ISBNs in field 020. However, if your local practice has been to put Bookland EANs in field 024, you continue to have this option, even though it causes redundancy (same number in fields 020 and 024).

MARC coding practice

The table below summarizes how to code EANs and ISBNs.

Number Field 1st Indicator 2nd Indicator Subfield
EAN 024 3 any ‡a
10-digit ISBN 020 blank blank ‡a
13-digit ISBN 020 blank blank ‡a


image of bar code

Authority and Holdings formats

You can also put both ten- and thirteen-digit ISBNs in field 020 in Authority and Holdings records.

ISBN conversion

OCLC will run a one-time conversion of ISBNs in existing WorldCat records in late 2006, as described below. However, ISBNs in records created after the one-time conversion will not be moved.

Whenever the system creates a field 020, the indicators are blank and the system-generated ISBNs are put in subfield ‡a.

  • Each ISBN is put in its own field 020
  • Rules for copying non-ISBN data in fields 020:
    • 020: Subfield ‡z is not copied to any other field.
    • 020: All data following the ISBN in subfield ‡a is copied to any new 020 field. Other subfields are not copied.
  • Field 024 is converted only under the following conditions:
    • Only the thirteen-digit ISBN will be moved to field 020. All other data is ignored.
    • The 1st indicator is "3"
    • Subfield ‡a contains a thirteen-digit ISBN with a prefix of "978" or "9791" through "9799"

Summary of OCLC system processing

The two main ISBN conversion actions that OCLC systems will automatically execute are:

  • Store ten-digit ISBNs in field 020 ‡a and generate a thirteen-digit ISBN (if not already in the record).
  • Store thirteen-digit ISBNs in field 020 ‡a and generate a ten-digit ISBN (if not already in the record).

The two sections below describe the complete set of system processes OCLC will perform.

Conversion

The table below describes the conversion process OCLC will run on WorldCat in late 2006.

Number Field System action
10-digit ISBN 020 ‡a Generates 13-digit ISBN (if not already in record).
13-digit ISBN (978) 020 ‡a Generates 10-digit ISBN (if not already in record).
13-digit ISBN (9791-9799) 020 ‡a No system action.
13-digit ISBN (not 978, 9791-9799) 020 ‡a No system action (Invalid ISBN).
13-digit ISBN 020 ‡z If valid, moves to 020 ‡a and generates 10-digit ISBN (if not already in record). If invalid, no system action
13-digit EAN (978) 024 indicator 3 Generates 10- and 13-digit ISBNs (if not already in record). Deletes 024 if it contains only ‡a.
13-digit EAN (9791-9799) 024 indicator 3 Generates 13-digit ISBN (if not already in record).
13-digit EAN (not 978, 9791-9799) 024 indicator 3 No system action (Number is not a Bookland EAN or ISBN).
EAN (not 13 digits) 024 indicator 3 No system action (Number is not a Bookland EAN or ISBN).


After conversion

The table below describes how OCLC systems process ISBNs after the WorldCat conversion in late 2006.

Number Field System action
10-digit ISBN 020 ‡a Generates 13-digit ISBN (if not already in record).
13-digit ISBN (978) 020 ‡a Generates 10-digit ISBN (if not already in record).
13-digit ISBN (9791-9799) 020 ‡a No system action.
13-digit ISBN (not 978, 9791-9799) 020 ‡a No system action (Invalid ISBN).


When Connexion generates ISBNs

In Connexion, the appropriate ISBN (if any, see "After conversion" table above) will be generated when you take the following actions:

  • Replace Record
  • Update Holdings
  • Produce and Update Holdings
  • Validate

    Note: ISBNs will not be generated for Connexion client offline validate commands
  • Export

    Note: In order to export a record with ISBNs in the Connexion client, you must first take the actions listed above before exporting. ISBNs will not be generated if you export a record without taking these actions first.

Deleting ISBNs

If a record contains two ISBNs and you delete one, the system will regenerate the one you deleted and add it to the record. To avoid this situation, delete both ISBNs.

3 OCLC Number Changes in MARC Records

Expansion of OCLC number

Currently, the OCLC control number is a fixed-length, eight-digit number. However, OCLC will soon reach the last eight-digit number. On November 12, 2006, WorldCat records will be able to have nine-digit OCLC numbers. The 100 millionth WorldCat record will be the first nine-digit number.

A sample file of records, some containing nine-digit OCLC numbers, is available on the Product Services Web site:

  Action
1 Go to the Product Services Web: http://psw.oclc.org/
2 Click Download sample records and reports.
3 The Records and reports screen appears.
4 Under Sample Records and Reports, click OCLC Bibliographic records sample file.
5 The log on screen appears. Type your authorization and password. Click Enter.
6 The Records and Reports screen appears. Click Download for the file you want.


Records containing OCLC numbers 1 through 99999999

The table below describes the 001 field in records containing OCLC numbers 1 through 99999999.

Tag Byte Value Definition
001     Control Number (NR)
  00-02 ocm OCLC designation
  03-10   Record number

(Right justified with leading zeros)
  11   Blank


Records containing OCLC numbers 100000000 and higher

The table below describes the 001 field in records containing OCLC numbers 100000000 and higher.

Tag Byte Value Definition
001     Control Number (NR)
  00-02 ocn OCLC designation
  03-11   Record number


Field 035

All bibliographic records output from OCLC systems will include the OCLC number from field 001 in field 035:

  • The 035 field will appear immediately before the first field greater or equal to 035, ignoring fields 040 and 066.
  • Both indicators are blank.
  • Subfield ‡a will include the OCLC number as a variable-length numeric string with no leading zeros and preceded by "(OCoLC)". Subfield ‡a will be present in all bibliographic records output from OCLC systems (except Connexion client 1.60).
  • Subfield ‡z will include the OCLC number from field 019 for cross-reference records which have been deleted and merged with the present record. Subfield ‡z is repeatable and will not be present in every record.

Example

035 ‡a(OCoLC)198765401

Exporting field 035

Records exported from Connexion browser and CatExpress will contain an automatically-generated 035 field containing the OCLC number.

Records exported from Connexion client 1.60 will not contain an automatically-generated 035 field containing the OCLC number. Connexion client 1.70 (release date: late 2006) will be able to export records with this kind of 035 field.

4 OCLC-MARC Changes

Field 007 changes

After November 12, 2006, uncoded positions in the 007 field will result in fill characters in OCLC-MARC output (previously, they were hyphens).

Example field Old output New output
c ‡b o ‡d u ‡e g ‡f u co ugu-------- co ugu||||||||
h ‡b d ‡d b ‡e g ‡f c--- ‡g c ‡j u hd bgc---c--u hd bgc---c||u


This change will be present in all bibliographic records output from OCLC systems (except Connexion client 1.60).

Transaction code changes

After November 12, 2006, the following transaction code changes will be implemented:

  • Transaction codes will be stored only in field 994 (previously, they were stored in Leader byte 22 and field 994).
  • Leader byte 22 will always contain value 0 (zero).

This change will be present in all bibliographic records output from OCLC systems (except Connexion client 1.60).

5 Appendix: History of the OCLC Number

Scope

This appendix describes briefly the various forms of OCLC numbers that OCLC has output in OCLC-MARC via subscription and export from various OCLC cataloging services.

OCLC has distributed other records with different kinds of control numbers. The records below are not part of this appendix because they are not WorldCat records.

Code Record type
oca OCLC-MARC authority records
bip (obsolete) Book-in Print database records
ccd (obsolete) CatCD original record (both bibliographic and authority)
har (obsolete) Harvard database record
pct PromptCat data record
pks (obsolete) Prism Keying Service record


Records output prior to June 28, 1981

Prior to June 28, 1981, the OCLC number was distributed in field 001 with the following structure:

Tag Byte Value Definition
001     Control Number (NR)
  00-03 ocl7 OCLC identifier
  11   Blank


Example

001 ocl70012345

Note: transaction date

Between June 30, 1980 and June 25, 1983, all output records included the transaction date following the control number in field 001, separated by a blank. Beginning June 26, 1983, the transaction date was moved to field 005 and no longer put in field 001.

Example

001 ocl70012345 800630

Records output between June 28, 1981 and the 100 millionth record in WorldCat

Includes all records output regardless of when the library updated or added the record. Records produced prior to June 28, 1981 but output after that date have the new structure:

Tag Byte Value Definition
001     Control Number (NR)
  00-02 ocm OCLC identifier
  11   Blank


Note: See Note: transaction date, above.

Date Example field
Prior to June 28, 1981 001 ocm00123456 800630
After June 28, 1981 001 ocm00123456


Records output after 100 millionth record in WorldCat

If the OCLC number is greater than 100000000, the following structure will be present:

Tag Byte Value Definition
001     Control Number (NR)
  00-02 ocn OCLC identifier


Example

001 ocn198765401



Cross reference field

Beginning in December 1979, for every record that is merged to another record, a field 019 (OCLC control number cross-reference) is created. It is added to the retained record and contains the OCLC number of the deleted record. For more information, see Bibliographic Formats and Standards, field 019.

Example

019 ‡a9849497 ‡a10625879


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