Reference distribution policy

All metadata that members register with us is made available through our various metadata search and API services. However, references have always been treated differently than all other metadata.

In July 2017 the Crossref board voted unanimously to remove the ability for members to make case-by-case opt-out choices, and the membership agreement was updated accordingly.

At the same time, the board also adopted a new policy for members to set a global account preference for treatment of references.

Table of contents

Reference distribution options

Around a third of our members include reference lists when they deposit metadata to register their content, usually in order to participate in our Cited-by service.

Members depositing references should contact our support team if they would like to change their setting to one of the following options:

Reference setting Description
Closed Your references are only used for the Crossref Cited-by service and are not distributed via any of the other Crossref interfaces.
Limited In addition, organizations that sign an agreement for our Metadata APIs ‘Plus’ service can access your references. (This is the default)
Open Everyone can access your references through our open APIs.

If your references are already set to ‘open’, or you are happy with ‘limited’ there is no need to contact us.

This policy comes into effect from January 1st 2018, when the default setting will be ‘limited’.

Background & rationale

Over the last ten years we have developed five machine interfaces and three human interfaces for accessing Crossref metadata. The organizations using Crossref metadata include publishers as well as third parties. For example—American Chemical Society, ORCID, Jisc, CHORUS, Elsevier, Altmetric, CCC, NASA, National Science Foundation, EBSCO, Springer Nature, Ex-Libris—and many hundreds of other publishers, platforms, researchers, and libraries.

The interfaces each offered slightly different metadata and features which was an inconsistent offering, and was confusing for both members and users. One of the features that was inconsistent is the case-by-case metadata opt-out we had been running for just one of the services, known as Enhanced CMS, which is for obtaining metadata specifically via the OAI-PMH interface.

Crossref was founded to enable a shared reciprocal linking and metadata exchange, removing the need for bilateral agreements between publishers and other service providers.

The best way to opt out of certain metadata sharing, is to not put it into Crossref. But there are a number of benefits to distributing references through Crossref, chiefly amoung them increased usage of your content—members benefit from increased usage when Crossref DOIs, metadata and references are propagated throughout the numerous scholarly communications systems that drive discoverability.


1) How do I know if I or my service provider includes references with our metadata deposits?

Please check with your production department or service provider; they should know. You can also query using our REST API with the has-references filter, using this query:*&rows=0 (your browser will need a json viewer plugin).

2) How do I find out whether our references are currently open or not?

An output from our REST API is in this table showing a list of the currently 362 members with some references Open. If you are not on this list then you likely have your references set to ‘limited’ right now unless you’ve specifically asked them to be set to ‘closed’.

Please contact our support team if you have any questions and click here to let us know if you’d like to change your setting. Please include your organization’s name and the relevant DOI prefix(es) (starting 10.nnnn).

Last Updated: 2018 March 19 by Ginny Hendricks