Subject heading fields 600-651 and genre terms (field 655) are to be used by any institution assigning headings based on the lists and authority files identified through the second indicator or subfield $2 of the field.  Field 653 is defined for headings that are not based on a standard thesaurus.

Prior to July 1985, subject headings input by institutions other than LC, LAC, NLM, or NAL were coded as 69X local subject headings.  The 69X fields were retained on the OCLC data base but were not output by OCLC to LC and were not distributed by the MARC Distribution Service–Serials.  The 69X fields are no longer retained in the master record, although 690 and 691 are still valid local OCLC tags.

First indicator

The first indicator in fields 600-611 signals the form of the heading and is specific to each type (e.g., personal, corporate name, etc.).  For instructions on its use see Headings - General Information.

Second indicator

The second indicator signals the source of the subject heading.  The values are defined as follows:

0    Library of Congress Subject Headings.

For subject headings based on the Library of Congress Subject Headings (LCSH) or its online version, its supplements, or the LC Name Authority File as maintained by OCLC.  Most CONSER records will have subject headings with second indicator value "0".  "Based on LCSH" is defined for use within CONSER as:

a.   Headings (or headings and subdivisions) found in the latest edition of LCSH, including the latest microfiche, printed version and supplements, or the online version.

b.   Headings consisting of a term in LCSH to which is added a subdivision according to the rules stated in the Subject Headings Manual, particularly subdivisions listed in the pattern lists, and place subdivisions formulated and applied according to the rules in the manual.

c.   Headings not printed in LCSH in the past but which have been used on LC copy in the past and which would not have changed under AACR2 (e.g., names of chemical compounds).

d.   Headings based on patterns given in multiples in LCSH or authorized by instruction in LCSH, e.g., Economic assistance, British, [French, etc.].

e.   Headings constructed with free-floating phrases e.g., … in art, etc.

1    LC subject headings for children's literature.

For children's subject headings based on LCSH and its published supplements (including Subject Headings for Children's Literature).

2    Medical Subject Headings.

For subject headings based on the Medical Subject Headings (MeSH) (in field 650 only) or the NLM authority files (in fields 600, 610, 611, 630, and 651).

3    National Agricultural Library subject authority file.

For subject headings based on the National Agricultural Library (NAL) subject authority file.  This indicator is no longer used in CONSER.

4    Source not specified.

For subject headings assigned from a controlled list when the source of the headings cannot be specified by one of the subject heading lists or authority files covered by second indicator values "0-3, 5-6" or by a code for a specific subject heading list in subfield $2 when the second indicator is set to value "7."  Indicator "4" is used in geographic name subject headings if the place name is not established in the authority file.

5    Canadian Subject Headings.

For subject headings based on the Canadian Subject Headings, including its supplements and on the LAC authority field English headings, except those which are valid LC headings and which are coded as "0."

6    Répertoire des vedettes-matière.

For subject headings based on the LAC authority file and on the Répertoire des vedettes-matière, issued twice a year in microfiche format.

7    Source specified in subfield $2.

For subject headings based on lists or authority files other than those listed above and for which identifying codes have been provided in subfield $2.


For a description of subfields $a through $t, see Headings - General Information.

$v  Form subdivision.

Subfield $v contains a form subdivision that designates a specific kind of genre of material as defined by the thesaurus being used.  A form subdivision in subfield $v is generally the last subfield in the field.  The subfield may be repeated if more than one form subdivision is used.  Subfield $v was implemented in LCSH on February 16, 1999.  In LCSH, form subdivisions are added to main headings or main heading/subdivision combinations to indicate what the item being cataloged is rather than what it is about.  Most form subdivisions may also be used as topical subdivisions for works about those specific forms.

650 #2 Medicare $v periodicals.

650 #0 Fisheries $z Alaska $v Statistics $v Databases.

$x  General subject subdivision.

This subfield identifies general subject subdivisions from LCSH.  Form subdivisions from other sources may be input in subfield $v.

650 #0 Medicare $x Statistics $x Periodicals.

The word "States" is treated as a general subdivision.

650 #0 Labor supply $z United States $x States $v Statistics $v Periodicals.

Dates that are used to identify a specific occurrence of an event and that do not qualify the subject in terms of time are treated as general subdivisions.

600 10 Reagan, Ronald $x Assassination attempt, 1981.

Subdivisions that qualify a subject in terms of the time in which works were written are general subdivisions.

650 #0 Art $x Early works to 1800 $v Periodicals.

$y  Chronological subject subdivision.

This subfield is used for dates or phrases that qualify a subject in terms of time.  Chronological subdivisions apply to the subject itself.

651 #0 Soviet Union $x History $y Nicholas I, 1825-1855.

650 #0 Art, Modern $y 17th-18th centuries $x History.

$z  Geographic subject subdivision.

This subfield contains the names of places used as subdivisions.  Treat as place subdivisions the names of jurisdictions qualified by information denoting historical periods or different governments.

650 #0 Women $x Employment $z United States $v Periodicals.

650 #0 Law $z Germany (Middle Ages) $x Sources.

650 #0 Education, Secondary $z France $z Paris $v Directories.

650 #0 Law reports, digests, etc. $z Argentina $z Buenos Aires (Province)

$2  Source of heading or term.

This subfield is used only when the second indicator is set to value "7".  The subfield contains a code identifying the source list from which the subject heading or term was assigned.  For a listing of codes see Source Codes for Vocabularies, Rules, and Schemes (Subject Heading and Term Source Codes).

650 #7 Educational buildings $z Washington (D.C.) $y 1890-1910. $z lctgm

Editing instructions


Spell out in full words occurring in subject added entries except for abbreviations used in established name headings.

651 #0 United States $x Description and travel $v Periodicals.

610 20 Population Research Service (U.S.)

651 #0 Houston (Tex.)


1.   Input a period at the end of each field unless some other form of punctuation is already present.

650 #0 Flour and feed trade $v Periodicals.

651 #0 United States $x Foreign relations $y 1981-

651 #0 Siena (Italy)

2.   Do not input hyphens between each subdivision.  These are provided by a user's print program.

3.   Whenever an open date precedes an additional subdivisions, leave one space between the hyphen of the date and the following subfield code in addition to the space preceding the delimiter.

650 #0 Economic history $y 1990-  $x Statistics $v Periodicals.

Initial articles

LC does not establish topical headings beginning with initial articles.  Initial articles are input in name headings when the subject or subfield begins with a personal or geographic name and the intent is to file on the article.

Heading:   Los Olmos (Tex.)

Input as:  651 #0 Los Olmos (Tex.)

Heading:   La Berthenoux (France)

Input as:  651 #0 La Berthenoux (France)

Heading:   California.  Los Angeles Regional Water Pollution Control Board.

Input as:  610 10 California. $b Los Angeles Regional Water Pollution Control Board.

Additional instructions

1.   LAC.

LAC assigns both English and French subject headings when separate English and French records are not created.  When the English and French subject headings are identical, the subject heading is entered twice.  The second indicator value "0" (if based on LCSH) or "5" (if based on Canadian Subject Headings) is assigned to the English subject heading.  Second indicator value "6" is assigned to the French subject heading.

650 #0 Prime ministers $z Canada $x Public opinion.

650 #6 Premiers ministres $z Canada $x Opinion publique.

650 #5 Prime ministers $z Canada $x Spouses.

650 #6 Premiers ministres $z Canada $x Conjoints.

2.   Newspapers.

CONSER catalogers assign topical and geographic subject headings to newspapers, following Subject Headings Manual (H 1920).  Topical subject headings include those for ethnic newspapers and newspapers that primarily represent a subject focus.

650 #0 French Canadians $z New Hampshire $v Newspapers.

650 #0 Slavery $z United States $x Anti-slavery movements $v Newspapers.

650 #0 Labor movement $z Maryland $z Baltimore $v Newspapers.

Geographic name subject headings are used for newspapers as a means of providing access to the publication's area of coverage.  Authority work for place names in geographic name subject headings is not required.

3.   Choice of tags.

For instructions on the proper tagging of subject headings, consult each field and the special list given in Subject Headings Manual (H 405) or "Appendix E" in MARC 21 Bibliographic.

Related fields, etc.

Headings - General Information, Appendix J

See also:

6XX  Subject Access Fields

Variable Data Fields

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

CONSER Editing Guide:  Contents