Library of Congress

Program for Cooperative Cataloging

The Library of Congress > Cataloging, Acquisitions > PCC > BIBCO > Policy on classification numbers in BIBCO records

Rev. Sept. 8, 1998; corrected Jan. 9, 2001

FAQ on LC Classification numbers in BIBCO records

Class numbers in BIBCO records

The Standing Committee on Standards has received a number of questions from BIBCO libraries about how to interpret the provisions of the PCC Core Bibliographic Standards for Books with respect to class numbers. The following guidelines are intended to clarify the provisions of both the core and full record standards with respect to class numbers.

General provision

The books core record standard calls for assigning a class number from an established classification system supported in the MARC 21 format. The provision includes classification systems from any source (1) specifically identified in the format (e.g., fields 050, 060, 070, 080, 082, 084, 086) or (2) included in the code list for relators, sources, description conventions.[1] Purely local call numbers, accession numbers, shelf numbers, etc. may be input in local call number fields.


The purpose of including class numbers in PCC records is to provide classified access and to provide the basis for building a call number through one of the classification systems supported by MARC 21. Any class number provided should aim to be in a form that is most useful to the widest number of potential users of that classification system.

Class number

Some classification systems distinguish between the general and the particular. Data that relate to the general make it possible to group items of similar intellectual content (class number). Data that relate to the particular make it possible to individualize items and subarrange them within a group (e.g., author Cutter, work Cutter, etc.). In applying such systems to PCC records, only a class number is required. PCC libraries always have the option of supplying a full call number, but it is not a Program requirement.

What constitutes a class number is determined by the nature of the classification system and the agency authorized to develop and maintain it. For example, in the Library of Congress Classification system, class numbers sometimes also include topical Cutter numbers.


Individual core standards specify when a class number is required. These requirements apply also at the full level. Optionally, a class number or call number may be supplied in records for materials in which the standard does not require such a number. If a library does not classify materials for which a PCC standard requires a class number, the library may either supply one in particular cases or not label the record a PCC record.

General application

To the extent practicable, supply a class number according to the current practice specified by the authoritative agency responsible for the development and maintenance of the classification system. Apply this guideline also in those cases in which a call number is optionally supplied. If a library employs a variant practice in using a particular classification system, such forms can be recorded in a local field in addition to the standard form recorded in the field appropriate to the classification system.

A PCC library is only responsible for a classification number from the primary scheme in use by the upgrading library. If a classification number from another scheme appears in a record that a PCC institution upgrades as a PCC record, retain that number.

Library of Congress Classification

For BIBCO libraries using LC classification, assign a class number that adheres to LC practice and that includes the data that represent the topic (what the work is about). Depending upon the particular situation in the schedule, include data that would be in the $a subfield if that work were given a complete call number (to the extent that they are available in the classification schedule). Such data may include topical Cutters, work Cutters, artist numbers, geographic Cutters. Input the number in field 050 and use value "4" (Assigned by agency other than LC) in the second indicator position.

If a BIBCO library employs variant practices in assigning non-standard topical Cutter numbers or literary author Cutter numbers, etc., the local number may be input in a local call number field in addition to the LC conformant number in 050.

Dewey Decimal Classification

For BIBCO libraries using Dewey Decimal Classification, assign a class number using the current, full edition of the DDC appropriate to the specificity of the material in hand. Input the number in field 082 and use value "4" (Assigned by agency other than LC) in the second indicator position.

If a BIBCO library employs a variant, local number or a number suggested as an option in the DDC, the local number may be input in a local call number field.


If a PCC library using a PCC standard that calls for a classification number catalogs a work on a topic that is not yet represented in the classification system it uses, e.g., religious law in the case of the Library of Congress Classification, the PCC library may nevertheless designate the record a PCC record even though it necessarily lacks the required classification number. Optionally, the library may input the local number it uses in a local call number field.


  1. MARC Code List for Relators, Sources, Description Conventions, 2000.

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