What Went into RLG's Proposal to MARBI
On 31 January, 1999, the American Libraries Association's MAchine Readable Bibliographic Information committee, which advises the Library of Congress on extensions of the machine-readable cataloging format, passed RLG's Proposal 99-01, Enhancement of Computer File 007 for Digital Preservation/Reformatting.
Small modifications were made to the proposal immediately prior to approval for incorporation in the next update to the MARC 21 Format for Bibliographic Data publishing the new 007(c) values. Implementation by systems supporting the national databases (Library of Congress, RLG, and OCLC) followed.
The 007c had already existed as a place to encode information about computer files, but in no way addressed the types of information needed for describing digitally reformatted materials. This meant, however, that it was necessary to expand, rather than replace, the existing Computer File 007 values so as not to invalidate hundreds of records employing the current 007 computer file values to describe software, text files, etc.
For this reason the RLG group's recommendations included the original bytes of the field (007/00 - 007/05) with slight modification, and added eight new, optional bytes designed specifically to convey desired preservation and/or reformatting information. The approved proposal allows for an 007—Electronic Resource field of either 6 or 14 bytes, depending on whether information about long-term preservation is needed.
A note on 583: at the time the RLG group began its work, a contender for carrying digital reformatting information was the 583 Action Note field. (Today, the MARC 21 Web site defines this as "A copy-specific field that contains information about processing, reference, and preservation actions. For those using the field to record preservation activities, a list of Standard Terminology for the MARC Actions Note Field is available." This list is recommended but "not currently part of the MARC 21 format documentation.")
The group acknowledged efforts made through 1996 to use the 583 field to convey preservation, conservation, and retention information. Participants knew, however, that consensus on the encoding practice (and level of required coding) would not be reached for some time. They believed the control field 007 for computer files might be more appropriate for some of the information planned to appear in the 583 field, and they concluded that 007 expansion and use could be recommended and achieved more quickly.