Provisional Policy for 13-Digit ISBNs
Background: In Jan. 2005, the ISO standard was revised to change the ISBN structure from a 10 digit to a 13 digit number to increase numbering capacity. There was a transitional period between Oct. 2004 and Jan. 2007 when both 10 and 13 digit ISBNs may be assigned. If a publisher includes a 13 digit ISBN on an item, it must be paired with a 10 digit ISBN. The 13-digit ISBN is created by adding 978 to existing 10-digit ISBNs and recalculating the check digit. (See the LC example following.)
LC practice is described in LCRI 1.8.
"For CIP and other bibliographic records created after October 1, 2004 and before January 1, 2007, that contain pairs of ISBN 13 and ISBN 10, group them by manifestation in repeated MARC 21 020 fields, with the ISBN 13 input preceding the ISBN 10, each number qualified as appropriate.
020 ## ‡a 9781873671000 (hardbound)
020 ## ‡a 1873671008 (hardbound)
Continue to follow the guidelines stated above for ISBN 10 except to insure clarity, qualify each ISBN 13/ISBN 10 pair by the manifestation to which it relates. Prefer the term used in the source when it is judged to convey a condition intelligibly. For a hardbound resource, there is no attempt to use a consistent term other than to use one that conveys the condition intelligibly. Continue the practice of giving the ISBN, now a pair, related to the manifestation represented by the bibliographic record first. Note : If only an ISBN 13 is provided without an ISBN 10, do not input the ISBN 13; during the period January 1, 2005-January 1, 2007 when ISBN 13 is provided it is always to be paired with ISBN 10."
1. In general, for preliminary record creation by acquisitions staff handling orders, follow LC practice when creating the bibliographic order record from a citation if both 10- and 13-digit ISBNs are given, i.e., paired 020s, first 020 has the 13-digit number. If the citation only provides an unpaired 13-digit ISBN at the point of ordering, then staff may ignore the LC practice and enter the 13-digit ISBN in 020, with the understanding that if the record only has a 13-digit ISBN in 020, the chances of duplication may be increased.
2. Copy cataloging and acquisitions (order/in-process) records exported from OCLC:
- If the record has paired 020s, leave as is.
- If the record has a 024/020 pair, leave as is.
- If the record has only a 024, leave as is.
Note that 024 may include numbers other than the 13 digit ISBN. These numbers are intended to be entered in 024 according to the ISO standard. The YUL policy aims to avoid retagging these numbers by mistake, and also to avoid time spent retagging even when the number is a valid 13-digit ISBN, since there is no apparent benefit to doing so. Our batchmatching source, should we run it during the 2005-2007 period, will be OCLC, and the in-process record may have to match on source copy with 024 in any case. Voyager is expected to have an index that will search both 020 and 024 by 2007.
3. Original Cataloging. Follow LC practice described in LCRI 1.8.
4. Until the Voyager composite index is available, users are encouraged to search by 10-digit ISBN rather than 13-digit ISBN in Voyager.