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About OCLC-MARC records

Find out more about OCLC-MARC records.

OCLC-MARC records describes records produced since November 1993. It also lists documentation that describes records produced before November 1993.


OCLC-MARC Records describes the record structure, character sets, and exchange media formatting for OCLC-MARC records via electronic file transfer, and via export. This manual also provides a list of content designators and their names.

Audience for this manual

OCLC-MARC Records assumes familiarity with ANSI (American National Standards Institute) standards associated with MARC record processing. It assumes a general knowledge of computerized data processing and data processing in libraries.

Type of records

OCLC-MARC records can be bibliographic records or authority records. An OCLC-MARC record is composed of three elements:

  • The record structure
  • The content designation
  • The data content of the record

OCLC-MARC record structure

OCLC-MARC record structure is an implementation of the ANSI Information Interchange Format (ANSI Z39.2). This manual describes OCLC-MARC record structure following the outline of ANSI Z39.2 and indicates the specific choices made for OCLC’s implementation of the standard.

OCLC-MARC record content designation

This document lists tags, fields, indicators, and data elements for OCLC’s implementation of ANSI Z39.2. Much of the information in this document is based on information distributed by the Library of Congress in the following publications: MARC 21 Format for Bibliographic Data, MARC 21 Format for Authority Data, and MARC 21 Format for Holdings Data.

OCLC-MARC record content

For OCLC standards for record content, see Bibliographic Formats and Standards and Authorities: Format and indexes.

Typographical conventions

Throughout this document, the following typographical conventions are used:

Typographical conventions - Table
Convention Description
0 The graphic 0 represents the digit zero. This character must be distinguished from the uppercase alphabet letter O.
Blank The graphic symbol Blank is used for blank.
The graphic symbol ‡ is used for the delimiter portion of a subfield code.
/ The graphic / is used to specify character positions of the leader, directory, and fields 007 and 008, e.g., leader/06, 007/00, and 008/12.
1 The graphic 1 represents the digit one. This character must be distinguished from the lowercase alphabet letter l (el) and uppercase alphabet letter I (eye).
The graphic ■ represents a fill character.

Previous editions of documentation

Since record processing specifications change, OCLC makes the following documents available if you need to process OCLC-MARC records produced during the periods listed:

Previous editions of documentation - Table
Records produced Document
November 1993–December 2000 Tape and Export Record Formats Change Notices 1–9 and Technical Bulletins 221, 228, 231, 232, and 236–241
November 1990–November 1993 OCLC-MARC Tape and Export Record Formats
July 1989–November 1990 OCLC-MARC Tape Format, Second edition
September 1984–July 1989 OCLC-MARC Tape Format, First edition
January 1981–September 1984 OCLC-MARC Subscription Service Documentation, Fourth edition
April 1978–January 1981 OCLC-MARC Subscription Service Documentation, Third edition
December 1976–April 1978 OCLC-MARC Subscription Service Documentation, Second edition
May 1974–December 1976 OCLC-MARC Distribution Service Specifications for Magnetic Tapes containing Catalog Records for Monographs and Serials, First edition


Each document covers different time periods. New editions do not supersede previous editions. Do not discard previous editions.

Use of the word obsolete

In OCLC-MARC Records, any element, value, field, subfield, etc., marked obsolete is no longer valid. Current records will not contain these invalid codes. However, records supplied from archives (e.g., OCLC Bibliographic Snapshot service records) may contain obsolete MARC coding.

OCLC services

In addition to export from OCLC Connexion™, the following OCLC services provide OCLC-MARC records:

OCLC services - Table
OCLC service Description
OCLC Contract Cataloging services Provides customized solutions to help libraries eliminate cataloging backlogs, manage current cataloging, or handle special formats. Libraries receive full OCLC-MARC bibliographic records.
WorldShare Collection Manager Helps you manage your library’s metadata for electronic and print resources on a collection level. Five collection types (knowledge base, query, cataloging partner, data sync, and WorldCat updates) allow you to receive and edit the information you need to save your staff time and help your users find and access resources through your catalog. Plus, with Collection Manager, you can set and delete WorldCat holdings.
WorldShare Record Manager Allows you to create new and enrich existing items in WorldCat with efficient, record-at-a-time metadata management for your physical and electronic materials using either a MARC 21 editor or a Text View editor. Plus, with Record Manager, you can set and delete WorldCat holdings and export bibliographic records.