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DATE: May 25, 2018

NAME: Designating Access to Online Resources in Field 856 in the MARC 21 Formats   

SOURCE: OCLC and the German National Library, for the Committee on Data Formats

SUMMARY: This paper proposes adding a new subfield to field 856 (Electronic Location and Access) containing a numeric designator indicating accessibility (restricted, open, or partly restricted) to the online resource linked in the URI in subfield $u. For the purposes of this paper, an “open access” document can be reached without requiring payment or a login.

KEYWORDS: Field 856 (All formats); Electronic location and access (All formats); Subfield $e, in field 856 (All formats); Subfield $7, in field 856 (All formats); Access to online information resources (All formats); URIs

RELATED: 2018-DP11

05/25/18 – Made available to the MARC community for discussion.

06/23/18 – Results of MARC Advisory Committee discussion: The use case for a binary coding between "open access" and "restricted access" (values 1 and 0) was readily acknowledged. Significant discussion occurred around the "mixed access" (value 2) possibility for aggregate resources. There was willingness to defer on development of value 2 in order to expedite implementation of values 1 and 0, which were the vast majority of cases and for which need is most pressing. $7 would be preferable as a destination for the coding, as the DNB was proposing $e for a textual analogue in its complementary paper, 2018-DP11. It was observed that the entire 856 field was developed early in the Internet era and was formulated to encompass a variety of mechanisms, some of which have been superseded, and data elements, later found to be unnecessary with the development of the URI; so it may be appropriate to review and overhaul the field, with even the exceptional practice considered of redeploying some subfields for new uses. The paper will return as a proposal, likely in conjunction with developments from 2018-DP11.

Discussion Paper No. 2018-DP10: Designating Access to Online Resources in Field 856


1.1. Historical background

Field 856 contains information needed to locate and access an electronic resource.

In a bibliographic record, the field may be used for a resource when that resource or a subset of it is available electronically. In addition, it may be used to locate and access an electronic version of a non-electronic resource described in the bibliographic record or a related electronic resource.

In an authority record, the field may be used to provide supplementary information available electronically about the entity for which the record was created.

In a holdings record, the field identifies the electronic location containing the resource or from which it is available. It also contains information needed to retrieve the resource by the access method identified in the first indicator position. The information contained in this field is sufficient to allow for the electronic transfer of a file, subscription to an electronic journal, or logon to an electronic resource. In some cases, only unique data elements are recorded which allow the user to access a locator table on a remote host containing the remaining information needed to access the resource.

In a classification record, the field may be used for a resource when that resource or a subset of it is available electronically. In addition, it may be used to locate and access an electronic version of a non-electronic resource described in the classification record or a related electronic resource. This field may also be used to link to an electronic resource intended to supplement the classification scheme, e.g. an image of a map.

In a community information record, the field contains the information needed to locate and access electronic information pertaining to a community service such as the service or event website or related resources.

Currently, catalogers may use the 856 in conjunction with the 506 MARC field to denote restrictions on access of the URLs contained in the 856. Indicating access using the 506 field applies to an entire record and varies with the content of text strings used, cf. OCLC and The German National Library propose that there is a need to consider the 856 as an individual field to determine access to an item, as a complement to the current use of the 506 field in conjunction with the 856 field for the following reasons:

In provider-neutral cataloging (, there is “a single bibliographic record that describes all manifestations of an online resource regardless of which content publisher or aggregator is making the manifestation available.”  Current P-N guidelines do not specifically provide for any indication of open access or restrictions to access in an easily identifiable machine-readable form. Use of field 506 (Restrictions on Access Note) is restricted “only for records for DLF Registry of Digital Masters, HathiTrust Digital Library, and other digital preservation projects.” But even in these instances, text strings may be misinterpreted or misused in ways that a coded value would not be.

1.2. Current definition of Field 856

Field 856 is structured identically in the MARC Bibliographic, Authority, Holdings, Classification, and Community Information formats, although the definition and scope differ slightly from format to format. The Bibliographic field 856 is currently defined as follows:

Field Definition and Scope
Information needed to locate and access an electronic resource. The field may be used in a bibliographic record for a resource when that resource or a subset of it is available electronically. In addition, it may be used to locate and access an electronic version of a non-electronic resource described in the bibliographic record or a related electronic resource.
See the Guidelines for the Use of Field 856 for a more thorough discussion on the use of field 856.
Field 856 is repeated when the location data elements vary (the URL in subfield $u or subfields $a, $b, $d, when used). It is also repeated when more than one access method is used, different portions of the item are available electronically, mirror sites are recorded, different formats/resolutions with different URLs are indicated, and related items are recorded.


Catalogers deal with open access electronic resources on a regular basis. Typically, an entire record has been marked as open access, if it is marked at all. In provider neutral-cataloging, however, multiple URIs may be attached to a bibliographic record representing different aggregators or publishers that may allow different degrees of access to the same resource for any number of reasons. Defining a new subfield in field 856 containing a numeric, language-neutral designator indicating accessibility as restricted, open, or partly restricted would enable identification of the availability of full-text at the URI-specific field level. The formalization of identifying open access URIs enables library systems and librarians to surface specific URIs that lead their end users to open access content. This proposed change would enable library systems to look for a standardized code, associated with a specific URI, for open access, open access with restrictions, and restricted access rather than attempting to identify truly open access items by vendor or URI structure. The proposed change also harmonizes with existing provider-neutral practices by allowing vendors to indicate access at the URI-specific level.

This change could have significant positive impact on the discovery and access of articles, journals, monographs, etc. This proposed change applies only to access to electronic resources, not to usage rights.

Unlike many MARC subfields, which can take years to populate at any real scale, this newly-defined subfield may be populated in tens of millions of records through OCLC’s use of automated techniques in rapid order, thereby making this information widely available to institutions for use in their discovery systems.


Add a newly-defined subfield to field 856 to enable catalogers to associate a newly-defined numeric code to indicate restricted, open, or partly restricted access to an electronic resource. The two most likely candidates for this new subfield are subfield $e and subfield $7.

Subfield $e is the only remaining alphabetic subfield in field 856 that has never previously been defined. The only other subfield not currently defined is subfield $g, but it has a history, as follows, from the Content Designator History at

$g - Electronic name - End of range [REDEFINED, 1997]

$g - Uniform Resource Name [OBSOLETE, 2000]
Because subfield $g (Electronic name - End of range) was rarely if ever used, it was redefined as Uniform Resource Name in 1997. It was subsequently made obsolete in favor of recording the URN in subfield $u.

Subfield $7 has been defined and used in bibliographic records to indicate special MARC characteristics of the linked entry in fields 76X-78X (Type of Main Entry Heading, Form of Name, Type of Record, and Bibliographic Level) and in fields 800, 810, 811, and 830 (Type of Record and Bibliographic Level).  In the Bibliographic field 533 (Reproduction Note), subfield $7 contains coded information pertaining to the reproduction (Type of date/Publication status; Date 1; Date 2; Place of Publication, Production, or Execution; Frequency; Regularity; and Form of Item). In all instances, the definition of each code is position-dependent.

In the 7XX and 8XX cases, the use of subfield $7 was limited to MARC structural characteristics corresponding to an existing field indicator or MARC Leader value. In the case of field 533, the coded data elements correspond to various existing 008 character positions, which are both MARC structural characteristics and substantively reflective of the resource itself. If subfield $7 is chosen for use in field 856, it may be seen as an extension of the way it has been used in field 533, in the sense of containing coded data substantively reflective of the resource itself.


In field 856 (identical in the MARC Bibliographic, Authority, Holdings, Classification, and Community Information Formats), define new subfield:

Subfield $e – Access to Electronic Resource (R)


Subfield $7 – Control Subfield (R)

Position /0 – Access to Electronic Resource

Because subfield $u is repeatable, subfield $e/$7 must also be repeatable. In all cases, subfield $e/$7 should follow directly the subfield $u to which it applies. Generally, subfields $u and their corresponding subfields $e/$7 may be repeated only when both a Uniform Resource Locator (URL) and a Uniform Resource Name (URN), such as a PURL or a DOI, or multiple URNs are recorded.

0 – Restricted Access
The resource is not freely and openly accessible online.

1 – Open Access
The resource is freely and openly accessible online to everyone, without restriction.

2 – Restrictions Apply in Part, Hybrid Open Access.
Access restrictions apply to some or all of the online resource. These restrictions may include, but are not limited to, temporal restrictions (such as embargoes for a certain length of time), geographical restrictions, audience restrictions (such as availability limited to people with authorization or having a particular membership or affiliation), technical restrictions (requiring specialized software), etc.

In the future, the MARC Advisory Committee may want to consider complete reformulation of the 856, given the outdated nature of some of the contents of this field. However, that is not within the scope of this proposal.


Three examples employing the proposed subfield $e or $7 in bibliographic records

Examples employing a new subfield to indicate access level of the 856 subfield $u URL.  Subfield $7 is used in these examples, but subfield $e could also be used.


245 04 $a The sociological review.
856 40 $3 Full text available: Feb 1975-. (Due to publisher restrictions, the most recent 12 months are not available.). $u
856 40 $3 Google, n.s. v.20 1972 $u
856 40 $3 Google $u
856 40 $3 HathiTrust Digital Library, Full view $u $7 1
856 40 $u


245 00 $a Science & education.
856 40 $3 Google $u
856 40 $u $7 0 $z Full-text available from Springer LINK
856 40 $u $z Science & education -- Springer Online Journal Archives (Through 1996)
856 40 $z Full-text via EUI LINKS $u,guest&db=edspub&type=44&bQuery=AN%2062478&direct=true&site=pfi-live


245 14 $a The 10pm question : $b a novel / $c Kate De Goldi.
264 1# $a [Auckland] : $b [RHNZ Children's Ebooks], $c [2010]
856 42 $3 Publisher's website $u
856 40 $u $7 2 $z Archived copy available within National Library of New Zealand only $x Limited On Site Access


No impact.


7.1. Which subfield is preferred, subfield $e or subfield $7?

7.2. Does placement of the new subfield following the subfield $u seem like the best placement?

7.3. Does making the new subfield repeatable to correspond to the repeatability of the existing subfield $u make sense?

7.4. The structure of field 856 has been kept identical across all five MARC formats.  Are there any objections to defining the new subfield in each of the five formats?

7.5. Are the definitions of the numeric codes distinct and clear?

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