Related product I-Share

Standards for Bibliographic Records in I-Share

Page updated: June 22, 2023.

NOTE: This document has been superseded by the Cooperative Cataloging Policies for I-Share as of June 16, 2023. The document is presently retained for background only.

This document provides the basic standards required for bibliographic records in our shared I-Share environment. It is intended for those at I-Share libraries who catalog, edit files of bibliographic records, or perform local database maintenance as well as for those libraries beginning the process of joining I-Share.


The I-Share bibliographic environment includes the databases of member libraries and the shared union catalog. Individually, libraries provide descriptions of their resources, holdings, and item details, either creating records for unique objects, or selecting records from a number of sources. Sources range from OCLC’s WorldCat database, to the I-Share Union Catalog or other member libraries’ catalogs, to record sets from content vendors and other metadata providers. Quality of data across all sources may vary, and frequently present more than one record to describe the same resource.

Combined with the union catalog, I-Share member databases enable services for discovery and access to resources, sharing of materials, and cooperative collection development. To provide these services effectively, the shared records should present minimum barriers to identification and use of those records. To this end, CARLI recommends that members follow standards regarding record quality and limited duplication.

Bibliographic standards provide a common, base level of information necessary to help all library users find the resources they need.  Simultaneously, standards provide choices for individual libraries to build upon the base level and improve the quality of the shared data. Members of I-Share strive to maintain a shared bibliographic environment which will benefit all of our users.

This document presents standards that will help achieve this goal. While this document draws on OCLC’s documentation for guidance, the recommendations that follow should apply to the quality of bibliographic data in all I-Share databases, regardless of the source of those records.

Summary of Recommendations

  1. Each library should follow the current OCLC Bibliographic Formats and Standards for input cataloging as nearly as possible in all particulars, namely:

    a.    Input should be encoding level I except in those situations specified for level K.
    b.    Cataloging should be according to RDA (Resource, Description and Access) or the Anglo-American Cataloguing Rules, latest edition, and the Library of Congress's and the National Library of Medicine's interpretations thereof. See OCLC RDA Policy Statement. [Linked page no longer exists].
    c.    Input data should be correctly coded according to OCLC Bibliographic Formats and Standards.
    d.    Authorized access points should be RDA-compliant, as defined by RDA and the Library of Congress Program for Cooperative Cataloging Policy Statements (hereafter LC-PCC PS).  Access points that are listed in the LC authority file should always be used, rather than locally devised variants.
    e.    To avoid duplicate records, new records should be created for the OCLC database in those situations specified by OCLC. See Section 4 of OCLC Bibliographic Formats and Standards: When To Input a New Record.
    f.    Please note that OCLC is in the process of updating its online documents to reflect newly emerging standards. For example, it is incorporating references to RDA and LC-PCC PS. There are also new guidelines on who may replace an OCLC record and how. These and other updates may or may not be reflected in a given section of Bibliographic Formats and Standards at the time it is consulted. For details, see the Revision in progress section of OCLC’s Abstract & Revision Notes. Also see current revisions listed in OCLC’s Technical Bulletins.

  2. Each library should input all current cataloging and add location symbols for all material currently acquired, following the guidelines detailed in OCLC's WorldCat Principles of Cooperation.
  3. Each library should use the current edition of an authorized list of subject headings. For Library of Congress subjects, each library should also follow the instructions in Subject Cataloging Manual, Subject Headings.
  4. Each library should take care to code the call number fields correctly and to use the latest edition of any appropriate classification schedules.
  5. Each library should accept the responsibility to report errors it finds in the OCLC database, especially errors that affect retrieval. See Section 5.6  of OCLC Bibliographic Formats and Standards: Reporting Errors.
  6. Each library should have a program of quality control to ensure that these recommendations are followed.
  7. A library may choose to import catalog record copy from a number of different sources, but the quality of the record chosen should meet the standards as enumerated here.  Libraries importing records from vendors other than OCLC should follow I-Share recommendations regarding system control numbers and restrictions on record use outlined in Best Practices for Bibliographic Records for Non-OCLC Sources.
  8. When creating new catalog records for permanent holdings, each library should first create a master record in OCLC WorldCat.

Bibliographic Standards

Since every I-Share library is a member of OCLC, the basic cataloging standard for I-Share libraries is the Bibliographic Formats and Standards, issued by OCLC.  It prescribes the MARC format as the way to code cataloging for all uses. Further, it identifies those elements of the MARC format which should be present in every record and those which are optional. And, it identifies the source documents to be used in the preparation of data for the record.

The use of Bibliographic Formats and Standards is in fact a multilevel process. It is not only a standard itself, but it also calls for the use of other standards, which in turn call for yet other standards. Fortunately, careful use of Bibliographic Formats and Standards leads one quite clearly and logically to all the other sources one needs to use. The major features of the standard are detailed below.


Encoding level “blank” is used by authorized national bibliographic agencies and PCC libraries.  OCLC's Bibliographic Formats and Standards specifies two levels of cataloging for member libraries to use: level I (full-level cataloging), and level K (minimal level cataloging). In general, level I meets the requirements of second-level description in AACR2, and level K meets the requirements of first-level description in AACR2. The core elements for RDA records are similar to AARC2 first-level description, with additional elements required if data for certain core elements cannot be found in the resource ("core if" elements).

OCLC's Bibliographic Formats and Standards recommends that level I be used whenever possible. This should be the normal level of cataloging for all I-Share libraries. Level K is used when it is not possible or desirable to use level I. For I-Share libraries, specific categories of materials, as determined by local policy, may be entered at level K. One common misunderstanding is that level K permits complete freedom in the input of data. This is most definitely not the case; the standards for level K are just as rigorous as for level I.  The level I and level K standards detail, tag by tag, indicator by indicator, and subfield by subfield, if an element must be present in a record, if it is optional, or if it is not to be used (See Bibliographic Formats and Standards, chapter 2.4)


OCLC's RDA policy statement of March 31, 2013 indicates that libraries may add new unique records to the WorldCat database using any cataloging code that they wish.  Libraries may move to using RDA on their own timetable.  Libraries may upgrade AACR2 records to RDA, but may not change RDA records to AACR2 or add new AACR2 records if a matching RDA record already exists.  The ICAT Recommendations for Managing RDA Data in I-Share document of 2010, revised March 4, 2013 states that I-Share libraries are to follow the OCLC policy, but also encourages I-Share libraries to transition to cataloging in RDA.

I-Share libraries that choose to add AACR2 records should use the Anglo-American Cataloguing Rules, second edition, 2002 revision (AACR2 2002 rev.) and its amendments, in conjunction with a wide array of supporting documents and systems to determine appropriate practice in MARC records. Libraries that choose to add RDA records should use RDA in its online version (RDA Toolkit) or its print version (RDA: Resource Description & Access), in conjunction with related RDA policy statements and best practices documents issued by Library of Congress and other library organizations.


Bibliographic Formats and Standards is based on MARC21. It includes instructions for books, serials, and a variety of non-book media. It specifies exactly how the data for each field should be encoded. It describes the field, its indicators, its subfields, and the format(s) for which its use is appropriate. It shows, by many examples, precisely how data should appear in each field. This document also lists additional OCLC documentation needed by users of the OCLC system, such as MARC Code Lists, Cataloging: User Manual, Searching the Online Union Catalog, and various OCLC Technical Bulletins. (The Technical Bulletin series is issued by OCLC to give more explanation about the application of certain rules, to explain how OCLC works, or to describe changes in documentation.)


For original cataloging, use the Library of Congress (LC) Authorities for authorized access points (name and subject headings). Search the LC or OCLC Authority File or ClassificationWeb to verify forms of entry. If a desired access point is not in the Authority File, construct it according to RDA or AACR2 standards. The Library of Congress-Program for Cooperative Cataloging Policy Statements (LC-PCC PS) should also be followed. These policies can be found in the RDA Toolkit and in Cataloger’s Desktop. The OCLC document Authorities: Search Authority Files tells how to search the Authority File in OCLC and how to interpret the information in the records.


New bibliographic records should first be created in OCLC to ensure holdings are accurately represented. Then, they can be imported into local Voyager databases.  Bibliographic Formats and Standards specifies when new records are to be created and when they are not to be created (see When to Input a New Record). It emphasizes that OCLC WorldCat is to be searched thoroughly, using all relevant search strategies, before a new record is created.  The document Quality Assurance provides detailed instructions on enriching existing records, replacing them, and reporting errors.


Many records in the OCLC database are outdated, incomplete, incorrect, or substandard. Bibliographic Formats and Standards places no restrictions on how those records are used for card production or updates. But, every time an I-Share library uses one of those records, it becomes part of our consortial database, with all its flaws. If we are to have a proper database to use and to build on, then all records contained therein need to conform to a standard. The most reasonable standard is the same one as for original input records as detailed above.

In 2009, OCLC created the Expert Community. Members with full-level cataloging authorizations now have the ability to improve, upgrade, and make changes to the majority of WorldCat Master records. This has greatly simplified the error reporting process. Now, instead of submitting error change requests, members can correct errors and enhance many records themselves. For information on the Expert Community see Expert Community: Guidelines for Experts.  For records that fall outside of the Expert Community, errors should still be reported. 

Although no library can afford to spend the time it takes to report all the errors found in the OCLC database, each library should accept a commitment to participate in the Expert Community and/or submit change requests on a regular basis for errors found. When selecting errors to report, catalogers should concentrate on those that affect retrieval (e.g., errors in authorized access points, in the title field indicators, missing or incorrect ISBNs or ISSNs, missing or incorrect dates in the fixed field).   When selecting bibliographic records to enhance, catalogers should concentrate on enhancements that improve keyword and subject access (contents and summary notes, additional subject or genre headings).  Because some I-Share libraries have made these kinds of corrections and enhancements only in the I-Share database, catalogers should remember to check the I-Share Universal Catalog record for a resource to see if that record contains improvements that could be added to the OCLC master record.

Other Standards

Although Bibliographic Formats and Standards is the standard for coding cataloging data for AACR2 and RDA, it does not address, nor is it meant to address, certain other aspects of the record, such as subject headings, classification, or holdings and other local data. But standards are needed for some of these areas not covered by Bibliographic Formats and Standards. As stated before, all records created or used by every I-Share library will appear in the I-Share catalog, unless a library has chosen to suppress selected records following consortial guidelines for such suppression. To ensure that the necessary information is present in records in I-Share, additional standards are needed. Also take care when using the OCLC workforms as they have been adjusted according to the new requirements of RDA. Individual libraries/catalogers must adjust their preference of workform if AACR2 is desired.


Subject headings should conform to a nationally accepted standard, such as Sears, Library of Congress, or National Library of Medicine Subject Headings. The latest form of a subject heading should be used. When Library of Congress subject headings are used, they should be formulated according to the instructions in LC's Subject Cataloging Manual, Subject Headings.

When other thesauri or controlled vocabulary sources are used, they should be given MARC tags 6XX with a second indicator of 7 (6XX #7)  with the source specified in subfield 2 as prescribed by the MARC standard. Headings without a specified source (6XX #4) should not be created in the original cataloging process, but may remain in bibliographic copy if they provide a unique access point. 6XX #4 headings that duplicate LC Subject Headings in the same bibliographic record are candidates for deletion.

If locally devised subject headings are used, they should be given MARC tags 690 or 691. Geographic entities that are already established in the LC Authority File should be used (651 #0) in lieu of local name variations (691).


Classification is the area left most open to local practice. However, for that very reason, there need to be some standards so the validity of a classification number input on new records will be apparent to other users. For libraries using the Dewey Decimal Classification (DDC), subfield 2 of the 092 field should be filled in for new cataloging to show the edition of DDC used. For libraries using the Library of Congress or the National Library of Medicine classification schedules, the latest edition of each schedule, with its additions and changes, should be used. Also, for a library using either the DDC, LC, or NLM classification, any local adaptation of the schedules should be shown by coding the adopted number in field 099 (or in field 098, if applicable). Fields 090, 092, and 096 should be used only when the number is used with the same meaning it has in the schedules.


All I-Share libraries are OCLC participants and as such make commitments to contribute all current metadata and holdings information to WorldCat, as indicated in the WorldCat Principles of Cooperation and WorldCat Rights and Responsibilities for the OCLC Cooperative.

Each library’s holdings should be accurately represented in OCLC. This means that a library's OCLC holdings symbol should be added to all materials currently acquired and should be removed from those records no longer retained. Accurate holdings are important because OCLC’s shared catalog is used for resource sharing through WorldShare ILL. Holdings may be manually added or removed in OCLC. They may also be added by CARLI through ongoing backloading projects.
Backloading only sets a library’s holdings symbol on corresponding bibliographic records already present in WorldCat. The process will not remove a library’s holdings when records are deleted, nor will it add new bibliographic records. New bibliographic records should first be created in OCLC Connexion to ensure holdings are accurately represented. Then, they can be imported into local Voyager databases.  
OCLC provides training opportunities for using OCLC Connexion browser, OCLC Connexion client, and other services through their online OCLC Training portal. Instructor-led online courses, pre-recorded courses, and online tutorials are available for basic and advanced topics. Additional Connexion documentation is available at

History of this document

  • Superseded by Cooperative Cataloging Policies for I-Share, June 16, 2023.
  • Endorsed by the CARLI Board of Directors March 13, 2015. 
  • Updated December 2014 by the CARLI Technical Services Committee to incorporate RDA and other new protocols.
  • Updated October 2006 by the I-Share Cataloging and Authority Control Team to incorporate consortial and system name changes.
  • Approved by the ILCSO Board of Directors December 5, 2003
  • Approved by the ILCSO Users’ Advisory Group (IUAG) September 5, 2003
  • Proposed by the IUAG Consortial Cataloging and Authority Control Committee August 2003
    • As revised by Arnold Wajenberg, University of Illinois at Urbana-Champaign and Don E. Wood, Southern Illinois University at Carbondale (October 1989)
    • *Originally Based upon Illinois OCLC Users' Group STANDARDS FOR (OCLC) INPUT CATALOGING (October 1983)