Character position definition and scope:

The Base address of data character positions contain a five-character numeric string that indicates the first character position of the first variable control field in the record.  The 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 (including the Directory field terminator character)

The number is right justified and each unused position contains a zero (0).

Users typically do not have access to Leader/12-16; the entry is automatically generated by the system.

National Level Requirement for Leader/12-16:  Mandatory.

Related MARC fields or documents:

Variable Control Fields


For information on other Leader positions, select:


See also:

MARC 21 Format for Authority Data:  Contents