In January 2026, our new annual membership fee tier takes effect. The new tier is US$200 for member organisations that operate on publishing revenue or expenses (whichever is higher) of up to US$1,000 annually. We announced the Board’s decision, making it possible in July, and––as you can infer from Amanda’s latest blog––this is the first such change to the annual membership fee tiers in close to 20 years!
The new fee tier resulted from the consultation process and fees review undertaken as part of the Resourcing Crossref for Future Sustainability program, carried out with the help of our Membership and Fees Committee (made up of representatives from member organisations and community partners). The program is ongoing, and the new fee tier, intended to make Crossref membership more accessible, is one of the first changes it helped us determine.
It has been 18 (!) years since Crossref last deprecated a metadata schema. In that time, we’ve released numerous schema versions, some major updates, and some interim releases that never saw wide adoption. Now, with 27 different schemas to support, we believe it’s time to streamline and move forward.
Starting next year, we plan to begin the process of deprecating lightly-used schemas, with the understanding that this will be a multi-year effort involving careful planning and plenty of communication.
Scholarly metadata, deposited by thousands of our members and made openly available can act as “trust signals” for the publications. It provides information that helps others in the community to verify and assess the integrity of the work. Despite having a central responsibility in ensuring the integrity of the work that they publish, editorial teams tend not be fully aware of the value of metadata for integrity of the scholarly record. How can we change that?
Crossref was created back in 2000 by 12 forward-thinking scholarly publishers from North America and Europe, and by 2002, these members had registered 4 million DOI records. At the time of writing, we have over 23,600 members in 164 different countries. Half of our members are based in Asia, and 35% are universities or scholar-led. These members have registered over 176 million open metadata records with DOIs (as of today). What a difference 25 years makes!
In our 25th anniversary year, I thought it would be time to take a look at how we got here. And so—hold tight—we’re going to go on an adventure through space and time1, stopping every 5 years through Crossref history to check in on our members. And we’re going to see some really interesting changes over the years.
Cited-by supports members who display citations, enabling the community to discover connections between research outputs.
Scholars use citations to critique and build on existing research, acknowledging the contributions of others. Members can include references in their metadata deposits which Crossref uses to create links between works that cite each other. The number of citations each work receives is visible to anyone through our public APIs. Through our Cited-by service, members who deposit reference metadata can retrieve everything they need to display citations on their website.
Members who use this service are helping readers to:
easily navigate to related research,
see how the work has been received by the wider community,
explore how ideas evolve over time by highlighting connections between works.
Watch the introductory Cited-by animation in your language:
Cited-by begins with references deposited as part of the metadata records for your content. Learn more about depositing references.
A member registers content for a work, the citing paper. This metadata deposit includes the reference list. Crossref automatically checks these references for matches to other registered content. If this is successful, a relationship between the two works is created. Crossref logs these relationships and updates the citation counts for each work. You can retrieve citation counts through our public APIs.
Members can use the Cited-by service to retrieve the full list of citing works, along with all the bibliographic details needed to display them on their website.
Note that citations from Crossref may differ from those provided by other services because we only look for links between Crossref-registered works and don’t share the same method to find matches.
Obligations and fees for Cited-by
Participation in Cited-by is optional, but encouraged.
There is no charge for Cited-by.
Depositing references is not a requirement, but strongly encouraged if you are using Cited-by.
Best practice for Cited-by
Because citations can happen at any time, Cited-by links must be kept up-to-date. Members should either check regularly for new citations or (if performing XML queries) set the alert attribute to true. This means the search will be saved in the system and you’ll get an alert when there is a new match.
Depositing your own references is strongly encouraged if you use Cited-by. If you don’t, the citations you retrieve will not include those from your own works. This is likely to lead to under-reporting of citations counts by at least 20% and you are missing the opportunity to point readers to other similar works on your platform.
Also in the metadata is the number of citations a work has received, under the tag "is-referenced-by-count".
To retrieve the full list of citations you need be a member using Cited-by. While anyone can use an API query to see the number of citations a work has received, members can retrieve a full list of citing DOIs and callback notifications informing them when one of their works has been cited. Details of the citing works can be displayed on your website alongside the article.
Page maintainer: Martyn Rittman Last updated: 2021-February-09
