First indicator - Level of index term

#  No information provided

0  No level specified

1  Primary

2  Secondary

Second indicator - Type of term or name

#  No information provided

0  Topical term

1  Personal name

2  Corporate name

3  Meeting name

4  Chronological term

5  Geographic name

6  Genre/form term


a  Uncontrolled term (R)

6  Linkage (NR)

8  Field link and sequence number (R)

NOTE:  See MARC 21 Format for Bibliographic Data (653 Index Term - Uncontrolled) for code definitions not given below.


Field 653 contains terms that are not derived from a controlled heading system/thesaurus.  While CONSER participants may add subject terms in field 653, they are encouraged to supply headings from a controlled thesaurus (e.g., LCSH), whenever possible.

The use of this field provides an alternative to controlled vocabulary for titles receiving minimal level cataloging and other records that would otherwise go without subject index terms.  In the case of foreign publications, substantive nouns and adjectives can be translated into English.  This field can also be useful for current terminology that has not settled down sufficiently to permit establishing the concept in a subject authority record.

Editing instructions

1.   Capitalization is not standardized.

2.   Do not add ending punctuation unless it is part of the data.

653 ## Stamp collecting (United States)

3.   Do not add punctuation preceding an additional subfield $a unless the preceding term ends with punctuation as part of the data.

653 1# Ice, Sculpture, mounds, etc. $a Children's games

4.   Do not add spaces in initialisms, acronyms, or abbreviations.

653 ## S.C.U.B.A.

5.   Leave one space following a data element that contains an open-ended date when the date is followed by a subject subdivision.

653 ## Counter culture, 1950- $a Literary collections

First indicator - Level of index term

The first indicator specifies the level of the index term, distinguishing primary and secondary descriptors.

#    No information provided.

A blank indicates that no information as to the level of the index term is provided.

0    No level specified.

Value "0" means that no level is specified and is used when no decision is made whether the term is primary or secondary.

1    Primary.

An index term is considered primary (value "1") if it covers the main focus or subject content of the material.

2    Secondary.

A term is secondary (value "2") if it represents a less important aspect of the content of the material.


$a  Uncontrolled term.

Subfield $a contains the uncontrolled vocabulary index term.  The subfield is repeatable when more than one term at the level designated in the first indicator is assigned.

653 1# fuel cells $a molten carbonate $a power generation

653 ## Man $a Eyes $a Diseases

Related fields, etc.

Subject Headings - General Information

653 Index Term - Uncontrolled  (MARC 21 Format for Bibliographic Data)

See also:

6XX  Subject Access Fields

Variable Data Fields

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

CONSER Editing Guide:  Contents