Leader (NR)
MARC 21 Authority
October 2002
Indicators and Subfield Codes
No indicators or subfield codes; the data elements are positionally defined.
Character Positions
00-04 - Record length
05 - Record status
a - Increase in encoding level
c - Corrected or revised
d - Deleted
n - New
o - Obsolete
s - Deleted; heading split into two or more headings
x - Deleted; heading replaced by another heading
06 - Type of record
z - Authority data
07-08 - Undefined character positions
# - Undefined
09 - Character coding scheme
# - MARC-8
a - UCS/Unicode
10 - Indicator count
2 - Number of character positions used for indicators
11 - Subfield code length
2 - Number of character positions used for a subfield code
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12-16 - Base address of data
[number] - Length of Leader and Directory
17 - Encoding level
n - Complete authority record
o - Incomplete authority record
18-19 - Undefined character positions
# - Undefined
20 - Length of the length-of-field portion
4 - Number of characters in the length-of-field portion of a Directory entry
21 - Length of the starting-character-position portion
5 - Number of characters in the starting-character-position portion of a Directory
entry
22 - Length of the implementation-defined portion
0 - Number of characters in the implementation-defined portion of a Directory entry
23 - Undefined
0 - Undefined
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FIELD DEFINITION AND SCOPE
First field of an authority record. It is fixed in length at 24 character positions
(00-23). The Leader consists of data elements that contain numbers or coded values that
define the parameters for the processing of the record.
Character positions 20-23 comprise the Entry map for the Directory. They contain four
one-character numbers that specify the structure of the entries in the Directory. More
detailed information about the structure of the Leader is contained in MARC 21 Specifications for Record
Structure, Character Sets, and Exchange Media.
GUIDELINES FOR APPLYING CONTENT DESIGNATORS
■ CHARACTER POSITIONS
00-04 - Record length Computer-generated, five-character number equal to the length of the entire
record, including itself and the record terminator. The number is right justified
and unused positions contain zeros.
05 - Record status Relationship of the record to a file.
Used for file maintenance purposes.
a - Increase in encoding level Encoding level (Leader/17) of the record has been changed from o (Incomplete
authority record) to n (Complete authority record).
c - Corrected or revised Addition/change other than in the Encoding level code has been made to the
record.
d - Deleted Used when neither code s nor code x is applicable, or when an organization
chooses not to use code s or x.
Some level of manual intervention may be needed to affect the change in
bibliographic records because the deleted heading may or may not be carried as
a 4XX See From Tracing field in other authority records and a 682 field
explaining the delete may be present in the record marked for deletion.
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| Leader/05 |
d |
| 150 |
##$aFruit processing |
| 682 |
##$iThis heading has been replaced by the heading$aFruit-Processing,$ia heading not distributed because it uses a
freefloating subdivision controlled by a pattern heading.
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n - New Record is a newly input record.
o - Obsolete Record content is obsolete, but the record has not been deleted from a
file.
s - Deleted; heading split into two or more headings Record has been deleted from a file because the heading has been split into two
or more headings, requiring a new authority record for each. The heading from
the deleted record is included in each of the new authority records as a
tracing in a 4XX See From Tracing field. This specialized delete value supports
use of automated systems to carry out any necessary reviews, since when a
heading is split, a computer cannot automatically replace the old heading in
bibliographic records.
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| Leader/05 |
s |
| 150 |
##$aBuddha and Buddhism |
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| Leader/05 |
n |
| 100 |
0#$aGautama Buddha |
| 450 |
##$aBuddha and Buddhism |
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| Leader/05 |
n |
| 150 |
##$aBuddhism |
| 450 |
##$aBuddha and Buddhism |
x - Deleted; heading replaced by another heading Record has been deleted from a file and that a new authority record in which
the heading from the deleted record appears as a 4XX See From Tracing field has
been added to the file. (In a system where authority control is linked to the
bibliographic file, a computer can affect the one-to-one replacement indicated
by code x without manual intervention.)
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| Leader/05 |
x |
| 150 |
##$aOleomargarine |
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| Leader/05 |
n |
| 150 |
##$aMargarine |
| 450 |
##$aOleomargarine |
06 - Type of record Characteristics and definitions of the components of the record.
z - Authority data Content of the record constitutes an authority record. The specific kind of
authority record is identified by the code in 008/09 (Kind of record).
07-08 - Undefined character positions Both are undefined; each contains a blank (#).
09 - Character coding scheme
a - UCS/Unicode Makes use of characters from the Universal Coded Character Set (UCS) (ISO
10646), or Unicode™, an industry subset.
10 - Indicator count Computer-generated number 2 that indicates the number of indicators occurring in
each variable data field.
(An indicator character position contains a code which conveys information that
interprets or supplements the data found in the field.) In MARC 21, two character
positions at the beginning of each variable data field are reserved for
indicators; therefore, the Indicator count is always 2.
2 - Number of character positions used for indicators
11 - Subfield code length Computer-generated number 2 that indicates the number of character positions used
for each subfield code in a variable data field.
(Each data element in a variable data field is identified by a subfield code.) In
MARC 21, a subfield code consists of a delimiter ($) and a lowercase
alphabetic or numeric data element identifier; therefore, the Subfield code count
is always 2.
2 - Number of character positions used for a subfield code
12-16 - Base address of data Computer-generated, five-character numeric string that specifies the first
character position of the first variable control field in a record. The number is
right justified and each unused position contains a zero.
Number is the base from which the starting character position of all the other
fields in the record is addressed in the Directory. (The starting character
position in the Directory entry for each field of the record is relative to the
first character of the first variable control field rather than the beginning of
the record.) The Base address of data is equal to the sum of the lengths of the
Leader and the Directory, including the field terminator character at the end of
the Directory.
[number] - Length of Leader and Directory
17 - Encoding level Whether the authority record is complete.
A record, where complete or incomplete, that is being considered for modification
after its initial creation is identified by code b (Record is being updated) in
field 008/31 (Record update in process).
n - Complete authority record Record meets national-level record requirements for content and content
designation.
o - Incomplete authority record Authority record is incomplete because it does not yet contain all the
information needed for a complete record. The record may or may not meet the
national-level record requirements.
18-19 - Undefined character positions Both are undefined; each contains a blank (#).
20 - Length of the length-of-field portion Always a 4.
4 - Number of characters in the length-of-field portion of a Directory entry
21 - Length of the starting-character-position portion Always a 5.
5 - Number of characters in the starting-character-position portion of a Directory
entry
22 - Length of the implementation-defined portion In MARC 21, a Directory entry does not contain an implementation-defined
portion.
0 - Number of characters in the implementation-defined portion of a Directory entry
23 - Undefined
Undefined; always contains a 0.
INPUT CONVENTIONS
System-Generated Elements - The following Leader elements are usually system generated:
| 00-04 |
Logical record length |
| 07-08 |
Undefined character positions |
| 09 |
Character coding scheme |
| 10 |
Indicator count |
| 11 |
Subfield code count |
| 12-16 |
Base address of data |
| 20-23 |
Entry map |
It is common for default values in other Leader elements to be generated automatically
as well.
Capitalization - Alphabetic codes are input as lower case letters.
CONTENT DESIGNATOR HISTORY
05 - Record status
d - Record deleted because heading is replaced by another heading [REDEFINED, 1983] [USMARC only]
d - Record deleted because heading is replaced by another heading [REDEFINED, 1997] [CAN/MARC only]
o - Obsolete [NEW, 2002]
x - Record deleted for reason not covered by other codes [REDEFINED, 1983] [USMARC only]
x - Record deleted (explanation may be present in field 682) [REDEFINED, 1997] [CAN/MARC only]
17 - Encoding level0 - Full level [OBSOLETE, 1997] [CAN/MARC only]
1 - RECON record [OBSOLETE, 1997] [CAN/MARC only]
3 - Incomplete record [OBSOLETE, 1997] [CAN/MARC only]