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    OCLC Control Number expansion

    • Article Type: General
    • Product: Aleph
    • Product Version: 20

    Description:
    WorldCat continues to grow! The OCLC Control Number is anticipated to reach one billion after July 1, 2013. At that point, OCLC will increase the length of the OCLC number to accommodate a variable length number string. If you use and/or store OCLC MARC bibliographic records and the OCLC Control Number, you will notice a change after July 1, 2013. You will need to check the systems at your institution that use OCLC MARC bibliographic records and the OCLC number. You may need to implement changes to ensure those systems will be able to successfully handle the longer OCLC number effective July 1, 2013.
    For example, publishers, vendors and others that partner with OCLC may be impacted as follows:
    • Integrated Library Service (ILS) vendors that use OCLC MARC bibliographic records to test compatibility with OCLC
    • Publishers, material suppliers and eContent providers that use OCLC MARC bibliographic records in their systems
    • Developers maintaining services that use OCLC Control Numbers
    Libraries may be impacted in the following areas:
    • Cataloging and IT librarians that download OCLC MARC bibliographic records to the library’s local system
    • Resource sharing librarians using third party ILL management programs that store or use the OCLC number for searching.
    • Reference services librarians using WorldCat Local to help a patron locate an item
    Format of the OCLC Number…
    The OCLC Number resides in the MARC 001 field and may also be stored in other fields. The OCLC Number in the 001 field is formatted as follows, and may appear in one or more of these forms in the record:
    OCLC numbers 1 through 99999999:
    • “ocm” prefix
    • oclc control number, 8 digits, right justified with leading zeros and a blank space as the last character
    Example: ocm00012345
    OCLC numbers 100000000 to 999999999:
    • “ocn” prefix
    • oclc control number, 9 digits
    Example: ocn123456789
    OCLC numbers 1000000000 and higher:
    • “on” prefix
    • oclc control number, 10 or more digits
    Example: on1234567890 or on1234567890123
    When stored in the 035 field, the OCLC number is usually stored with the prefix (OCoLC) and without the “ocm”, “ocn” or “on” prefixes; for example: (OCoLC)1234567890
    When this change takes place… the “on” prefix will be used to identify OCLC Numbers that contain ten or more digits. Nine or eight digit OCLC Numbers will continue to use the “ocn” or “ocm” prefix as described above. The update to the OCLC Number is backwards compatible so that previously defined OCLC Numbers will not be impacted. Previously assigned OCLC Numbers will continue to work as before.
    What action should you take? If you use and/or store OCLC MARC bibliographic records and the OCLC Control Number, you will notice a change after July 1, 2013. You will need to check the systems at your institution that use OCLC MARC bibliographic records and the OCLC number. You may need to implement changes to ensure those systems will be able to successfully handle the longer OCLC number effective July 1, 2013.
    For more information…See more technical information regarding this change here (http://www.oclc.org/us/en/batchprocessing/number-expansion.htm). Also, visit the Web (http://www.oclc.org/batchprocessing/controlnumber.htm) to learn how OCLC Control Numbers are created and how OCLC Batchload services give libraries the ability to match, merge, format and synchronize OCLC Control Numbers between their local systems and WorldCat. To see new OCLC Control Numbers when they are assigned, visit Watch WorldCat Grow (http://www.oclc.org/worldcat/newgrow.htm). Questions? Please contact me at gabell@oclc.org or our Support Desk at support@oclc.org or 1-800-848-5800 (USA) or 1-614-793-8682.
    Sincerely,
    --Linda
    Linda Gabel
    Local System Vendor Access Program Liaison
    WorldCat Quality Management
    OCLC
    6565 Kilgour Place
    Dublin, OH 43017-3395
    800-848-5878, ext. 6374
    Fax: 614-718-7196
    email: gabell@oclc.org

    Resolution:
    Since there is no validation of the OCLC number and since the 035 is a variable-length field, there is nothing special that needs to be done: Aleph will accept such numbers without any problem.

    Also, we have found no problem in the handling of the longer OCLC numbers by the following fix_doc routines:

    fix_doc_create_035
    fix_doc_oclc
    fix_doc_oclc_2

    We suggest loading the test records which OCLC has provided in order to confirm these findings.

    Additional Information

    Expansion of the OCLC Control Number


    • Article last edited: 10/8/2013