Field definition and scope:

Field 020 contains the International Standard Book Number (ISBN) assigned to a monographic publication by designated agencies in each country participating in the program.  The field may include terms of availability and canceled or invalid ISBNs, such as ISBNs with invalid check digits or that are not applicable to the item being cataloged.  It may be repeated for multiple numbers associated with the item (e.g., ISBNs for the hard bound and paperback manifestations; ISBNs for a set as a whole and for the individual parts in the set).

Each field contains all the information relevant to one ISBN, or if no ISBN exists, relevant to the item being cataloged.

The initialism ISBN, the phrase ISBN (invalid), and the hyphens embedded in the number are not carried in the MARC record.  (The ISBN is an agency-assigned data element.)

The National level record requirement for this field is Mandatory if applicable.

Field 020 is repeatable.

Guidelines for applying content designators:

For indicator and subfield code definitions and examples, National-level (NLR) and Minimal-level (MLR) record requirements, and designator repeatability, see table below:

Position

Description

NLR

MLR

Repeatability

Field 020

International Standard Book Number

A

A

R

Indicator:

 

 

 

 

First

Undefined; contains a blank

M

 

 

Second

Undefined; contains a blank

M

 

 

 

 

 

 

 

Subfield code:

 

 

 

 

$a

International Standard Book Number

A

A

NR

$c

Terms of availability

A

A

NR

$q

Qualifying information

 

 

R

$z

Canceled/Invalid ISBN

A

A

R

$6

Linkage

A

A

NR

$8

Field link and sequence number

O

O

R

Input conventions:

ISBN structure

Classes of ISBNs

Punctuation

Display constants

Content designator history:

Prior to 1977, field 020 was not repeatable and multiple ISBNs and related information were contained in repeatable subfields $a, $b, and $c.

Subfield $b - Binding information  (BK MP MU)  [obsolete, 1978]:  Prior to 1978, binding information was separately subfield coded.  In 1978, binding information became a parenthetical qualifier of the ISBN and subfield $b was made obsolete.

Subfield $c - Terms of availability  [new, 1974]:  Prior to the definition of subfield $c, bibliographic price information was contained in field 350 (Price).

Subfield $q - Qualifying information  [new, 2013]:  Prior to the definition of subfield $q in 2013, qualifying information was contained in subfield $a (International Standard Book Number) and subfield $z (Canceled/invalid ISBN).

Related MARC fields or documents:

880  Alternate Graphic Representation

RDA in MARC Bibliographic Data

Information and Documentation - International Standard Book Numbering (ISBN) (ISO 2108)

Library of Congress Rule Interpretations

See also:

0XX  Numbers and Codes

Variable Data Fields