MARC 21 defined:

#    Full level

1    Full level, material not examined

2    Less-than-full level, material not examined  [Not used]

3    Abbreviated level  [Not used]

4    Core  [Not used by CONSER]

5    Partial (preliminary) level

7    Minimal level

8    Prepublication level  [NSDP use only]

u    Unknown  [Not used]

z    Not applicable  [Not used]

OCLC defined:

I     Full level cataloging input by OCLC participating library

K    Less-than-full cataloging input by OCLC participating library

L    Non-LC and non-NLM cataloging added from tape

M    Less-than-full cataloging added from tapeloading


The encoding level indicates the degree of completeness of the machine record.  Five numeric values are defined in MARC 21 that are used in CONSER records (#, 1, 5, 7, and 8).  Four alphabetic encoding levels are defined for use in the OCLC online union catalog.

MARC 21 codes are used by Library of Congress (LC), Library and Archives Canada (LAC), and all CONSER members.  The order of codes is hierarchical, such that a lower level code may only be replaced with a higher level code or an OCLC code may be replaced by a MARC 21 code of the same level.  For instance, code "I" may be replaced with code "#".  However, a higher level code may not be replaced with a lower level code; e.g., code "I" could not be replaced with code "K".

MARC 21-defined codes

The codes described below are used by LC, LAC, and CONSER members when inputting new records or adapting existing records.

Level #  Full level (= CONSER standard record since 2007).

This level indicates that all of the elements specified as mandatory by the CONSER standard record guidelines ( are provided.  It also signifies that the cataloging is based on the examination of at least one issue of the serial.

MARC 21 Format for Bibliographic Data defines code "#" as "full level."  In 2007 CONSER began applying encoding level "#" to records that meet CONSER standard record guidelines, including records previously coded "#" (full level) and "4" (core level).  For CONSER records created after 1994, encoding level code "#" should generally be accompanied by one of the following 042 field codes:  lc, nlc, lcd, pcc.

Level 1  Full level, material not examined.

This level is used when the cataloging is taken from existing records (catalog cards, online records, etc.) without consulting an issue of the serial.  These records are generally incomplete in that certain fixed and variable field information cannot be known without the serial in hand.  This level is used primarily for retrospective conversion projects.  Level "1" may be upgraded to level "#" by verifying and completing the record after examination of an issue of the serial.

Level 2  Less-than-full level, material not examined.

This level indicates a less-than-full level record (i.e., a record that falls between minimal level and full) created from an extant description of the material (e.g., a printed catalog card) without reinspection of the physical item.  All the descriptive access points as found on the extant description have been transcribed; the authoritative headings, however, may not necessarily be current.  Level "2" would be used, for example, when only a subset of data elements is transcribed from a catalog card during retrospective conversion to the MARC 21 format.  Level "2" is not used in CONSER records.

Level 3  Abbreviated level.

This level is used for brief records that do not meet the National Level Bibliographic Record minimal level cataloging specifications.  Headings in the records may reflect established forms to the extent that such forms were available at the time the record was created.  Beginning in mid-2000, records from the CORC database created according to the Dublin Core metadata standard enter OCLC Worldcat as level "3" records.  The encoding level must be changed to the appropriate value in any records authenticated for CONSER.  In the past, level "3" was used on some minimal level records authenticated by LAC.  LAC minimal level records should be coded "7" when authenticated by LAC.  If a LAC minimal level record with the value "3" in the encoding level is found, change the encoding level to the appropriate code, but do not change the authentication code; leave nlc in the 042.

Level 4  Core.

This level indicates a less-than-full but greater-than-minimal level cataloging record that meets core record standards for completeness (see B6).  Level 4 became valid for input in OCLC in May 2000.  Prior to that time CONSER catalogers added the word "core" in field 039, which later became obsolete.  CONSER stopped using level 4 in 2007 after implementing CONSER standard record guidelines.

Level 5  Partial (preliminary) level.

On LC records, this level identifies a record containing full LC descriptive cataloging information but lacking an LC call number ("IN PROCESS" appears in the 050), LC subject headings, and other subject-related fields (e.g., 043).  LC changes code "5" to code "#" when it supplies these fields to the record.

LAC partial records contain all information normally provided in a full catalog record, including LC class numbers and full Dewey class numbers, but excluding subject headings.  Call numbers are assigned to non-government serials other than periodicals.  Use of code "5" on LAC records was discontinued after 1996.

Level 7  Minimal level.

This level indicates a record containing all elements specified as mandatory for minimal level cataloging in the MARC 21 Format for Bibliographic Data.  The salient feature of records with encoding level "7" is that subject headings are not likely to be present.  Three categories of records that carry this encoding level are listed below.

1.   Records based on the elements prescribed for minimal level cataloging as defined in Appendix C of the MARC 21 Format for Bibliographic Data.

2.   Records created by NSDP and ISSN Canada.  (Records created by NSDP prior to March 1, 1982 carry encoding level "I", which is machine converted to "#" prior to distribution of the record.)

3.   Records created by LAC.  Starting in March 1991, LAC creates minimal level records for certain categories of Canadian serials.  Data elements correspond to the 1st-2nd level of description as specified in AACR2.  Class numbers are assigned to non- government serials.  Call numbers are assigned to non-government serials other than periodicals.

NOTE:  When updating records in categories 1 or 2 to full level, a CONSER member should change encoding level "7" to "#".

Level 8  Prepublication level.

U.S. ISSN center supplies cataloging data based on information provided by the publishers in advance of publication.  The prepublication records contain the basic elements of description as well as the projected publication date (field 263).  The key title (field 222) is considered provisional until U.S. ISSN center receives a published issue or surrogate, at which time the record is updated for necessary revisions and the record is redistributed with an encoding level of "7".

Level u  Unknown.

Level "u" is used when an institution receiving or sending data having a local code in Leader/17 cannot adequately determine the appropriate encoding level of the record.  Code "u" replaces the local code.  This code is used primarily by utilities for the tape-loading of records.  The code is not to be used in records newly input or updated.  Level "u" is not used in CONSER records and, if found, must be replaced before the record is authenticated.

Level z  Not applicable.

Level "z" indicates that the concept of encoding level does not apply to the record.  Level "z" is not used in CONSER records.

OCLC-defined codes

OCLC encoding level codes "I" and "K" are input by OCLC members.  Codes "L" and "M" identify records tape-loaded into the OCLC online union catalog.  If any such records are subsequently authenticated and the encoding level is not changed, the alphabetic code is converted to the equivalent numeric code or "#" upon output to LC.

Level I  Full-level cataloging input by OCLC participating library.

Identifies a full level record input according to OCLC's Bibliographic Input Standards.  OCLC members use this code to input a new full level record or to upgrade an OCLC level "K" record to full level.  CONSER members change the code to "#".

Level K  Less-than-full cataloging input by OCLC participating library.

Identifies a record input online that does not fulfill OCLC specifications for a full level record.  OCLC members may upgrade level "K" records to level "I".  CONSER members change the code to a MARC 21-defined code, i.e., "7" or "#".

Level L  Non-LC and non-NLM cataloging added from tape.

Identifies records tape loaded into OCLC Online Union Catalog.  CONSER members change the code to a MARC 21-defined code.

Level M  Less-than-full cataloging added from tape-loading.

Identifies a less-than-full cataloging record tape-loaded from an institution other than the Library of Congress, the National Library of Medicine, the Library and Archives Canada, or the British Library.  CONSER members change level M to a MARC 21-defined code.

Related fields, etc.

C1, C2, Leader/05

Leader/17 Encoding level  (MARC 21 Format for Bibliographic Data)

See also:


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

CONSER Editing Guide:  Contents