Field 001 contains the control number assigned by the organization creating, using, or distributing the record.  In OCLC records, field 001 is system-generated for each record on that system.  It appears in the top left corner of the OCLC display; the tag "001" does not appear.

When a workform is retrieved, the word "NEW" is displayed at the beginning of the fixed field area following the designation "OCLC:".  When the record is added to the database, the control number appears in the same area.  Once a control number has been automatically assigned, it cannot be changed at the terminal.

LC tape processing and distribution

When processing the weekly CONSER tapes from OCLC, LC’s programs copy the contents of 010 subfield $a (Library of Congress Control Number) to the 001 and move the OCLC control number found in field 001 to field 035.

In records distributed by the Library of Congress, the LC control number is carried in both the 001 and 010 (subfield $a) fields.  In addition, the symbol "DLC" appears in field 003 (Control Number Identifier).  For further information see field 010.  For information on the Canadian control number, see field 016.

Related fields, etc.

003, 010, 016, 019, 035

001 Control Number  (MARC 21 Format for Bibliographic Data)

See also:

Variable Control Fields

Section E.  MARC 21 Format for Serials as Applied Within CONSER

CONSER Editing Guide:  Contents