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Appendix F - Format Changes

MARC 21 Authority
December 2025

This section is provided for the lists of format changes that accompany each update to the MARC 21 Format for Authority Data.

MARC 21 FORMAT FOR AUTHORITY DATA

FORMAT CHANGE LIST

Update No. 41, December 2025
This page documents the changes contained in the forty-first update to the 1999 edition of the MARC 21 Format for Authority Data. Update No. 41 (December 2025) includes changes resulting from proposals that were considered by the MARC 21 community since the publication of Update No. 40 (June 2025).

Format changes in previous updates can be found on the MARC Format Overview page.
■ New content designators:
Subfields
$i Relationship information (R) in 368 (Other Attributes of Person or Corporate Body)
$i Relationship information (R) in 376 (Family Information)
$i Relationship information (R) in 381 (Other Distinguishing Characteristics of Work or Expression)
$4 Relationship (R) in 368 (Other Attributes of Person or Corporate Body)
$4 Relationship (R) in 376 (Family Information)
$4 Relationship (R) in 381 (Other Distinguishing Characteristics of Work or Expression)

■ Changes in content designator names and definitions:
Subfield
$2 Source redescribed in 368 (Other Attributes of Person or Corporate Body)
Appendix
HData Provenance Subfields: Data Provenance Code List moved to https://www.loc.gov/standards/valuelist/dataprov.html. New codes bcp47 and dpets added.

■ Fast-track changes:
Subfields
$g Conversion date renamed Conversion date/time and redescribed in 884 (Description Conversion Information)

UPDATE 41 LOCAL PRINT GUIDE

The following sections and fields were created/changed in Update No. 41 and should be printed to keep a print copy of the format up-to-date. Changes appear in red.

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