Open Access linking and configuration options

Third Iron is committed to providing the best in class solution for Open Access article discovery for institutionally affiliated researchers via the LibKey and BrowZine suite of products. This article describes precisely where and how Open Access awareness is put to use and what configuration options are available for libraries in regards to Open Access materials.

LibKey Open Access awareness

The LibKey technology underpins all linking interactions within all Third Iron products. Individual products may extend this functionality and provide different options which are detailed below individually.

The basis of the LibKey linking philosophy is to be able to analyze available sources for a particular article within the lens of a particular institution and provide the most expedient and informed link to the user. This is calculated via a sophisticated AI Expert System. Generally, these rules mean that the following waterfall order of preference is applied to all links:

  1. Third Iron curated Gold and Bronze OA link
  2. Unpaywall curated Gold, Bronze or Hybrid OA link
  3. Library Subscription Access from the Publisher link
  4. Library Subscription Access from an aggregator link
  5. ILL / Document Delivery link

For a given article, a library may have available all of these different source types or none of them (if a library doesn’t have an ILL or Document Delivery service). Occasionally, a library have multiple options within each category and there is internal prioritization based on a number of factors that will influence the outcome within LibKey but always with an eye towards link reliability.

The LibKey treatment of Open Access knowledge from Unpaywall is unique in library systems as it smoothly integrates knowledge from the Unpaywall corpus while at all times insisting upon presenting only the Version of Record copy of the article. Unpaywall covers all different versions of the article and attempts via its API to present the best available version.  

However, sometimes that best available version can be an “Accepted Manuscript” meaning it is still perhaps in non-formatted form but has passed peer review as well as a “Submitted Manuscript” which means a version before any peer review/editorial edits were made. LibKey’s philosophy is that because LibKey is being used by institutions, it is preferable to link the user to an ILL/Document delivery form to retrieve the version of record rather than pass along non version of record items which can contain data/figures/conclusions, etc. that will have been altered between that copy and the final version which could result in a disservice to accurate scholarship.

Third Iron curated OA is the first in the waterfall as our team has hand-evaluated and curated this information and so knows it to be accurate. As the approach to retrieving and labeling data is different between Third Iron and Unpaywall, we believe the combination of the datasets in this manner yields the most accurate outcome. Third Iron data also supplements the Unpaywall links as well, sometimes turning an Article Link into a PDF link, for example. 

The benefits to injecting OA data are multiple depending on the context in which LibKey is being used. In open web situations (Nomad, Link, .io) this will enable about 9-10 Million more articles to be surfaced than might otherwise be available in a library’s subscriptions.

Additionally, LibKey greatly prefers to link based on identifiers and not OpenURL whenever possible. Generally, the OpenURL links are needed for aggregators, so by placing an identifier based URL to a publisher that is Hybrid Open Access above an aggregator holding that same article in a library collection, we are able to improve the quality of linking success.

In all cases where an OA article is known, no authentication challenge will be added to the link (proxy, VPN, SAML, etc.) as it is not needed which will accelerate the linking process.

Specific product augmentations

LibKey Nomad, LibKey Link,, LibKey Discovery (Primo and Summon integrations only)

These products have an additional extension of the above source order preference waterfall that looks like this:

  1. Third Iron curated Gold and Bronze OA link
  2. Unpaywall curated Gold, Bronze or Hybrid OA link
  3. Library Subscription Access from the Publisher link
  4. Library Subscription Access from an aggregator link
  5. “Live call” to Unpaywall to check for Green “Accepted Manuscript”
  6. ILL / Document Delivery link

When this occurs the links within these products are clearly labeled as being from Unpaywall and an Accepted Manuscript to alert users that this is not the version of record. This is being done as a “live call” to ensure the most up-to-date response from the Unpaywall data set.

Library available configuration options for LibKey

  1. Libraries can elect to disable the injection of Unpaywall curated Gold, Bronze or Hybrid OA links into the preference waterfall if they would like. Please contact to request this to be done. This might be done if the library is invested in collecting usage data via their proxy and thus wants to proxy as much content as possible. Note that the Third Iron Gold/Bronze OA is not configurable to disable.
  2. LibKey Discovery integrations in Primo and Summon can be configured by the library to disable or re-name the showcasing of the “Accepted Manuscript” links or turn off Unpaywall here altogether. Configurations are within each of the integration instructions: Primo Configuration | Summon Configuration
  3. Libraries can also elect (independently) to turn off the live calls to Unpaywall that will add the Green OA Accepted Manuscript links to Nomad, Link and .io.   This is a forthcoming feature that will be available in Fall 2021.

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