The Base address of data contains a five-character numeric string that indicates 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 (0).

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)

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

National and minimal level record requirements for Leader/12-16 for all formats are Mandatory.

For information about Leader/12-16 in a specific MARC format, select:

Leader/12-16 Base address of data  (Authority)

Leader/12-16 Base address of data  (Bibliographic)

Leader/12-16 Base address of data  (Classification)

Leader/12-16 Base address of data  (Community Information)

Leader/12-16 Base address of data  (Holdings)

To return:

Use the key.