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.
The Frankfurt Book Fair is the largest book fair in the world, and therefore a key event on our calendar. Held annually in Frankfurt, Germany, the 77th Frankfurt Book Fair (October 15–19, 2025) saw 118,000 trade visitors and 120,000 private visitors from 131 countries. The Crossref booth was located, as usual, in Hall 4.0 where all the stands with information about academic publishing can be found. Four Crossref colleagues attended the Book Fair this year, and in this blog post, you can read more about their meetings, experiences, and plans.Â
TL;DR. Metadata Manager will be retired at the end of 2025. Over the past four years, we have been developing a new helper tool to replace it, and that tool has now reached a stage of maturity that means we will be able to switch off Metadata Manager by the end of the year.
TL;DR: We no longer charge fees for members to participate in Crossmark, and we encourage all our members to register metadata about corrections and retractions - even if you can’t yet add the Crossmark button and pop-up box to your landing pages or PDFs.
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Research doesn’t stand still; even after publication, articles can be updated with supplementary data or corrections. When research outputs are is changed in this way the publisher should report and link it, so that those accessing and citing the content know if it’s been updated, corrected or even retracted. This also emphasizes the member’s commitment to the ongoing stewardship of research outputs.
Many people find and store articles to read later, either as PDFs on their laptop or on one of any number of reference management systems - when they come back to read and cite these articles, possibly many months later, they want to know if the version they have is current or not.
Removing Crossmark fees
To encourage even wider adoption of Crossmark, and to promote best practice around better reporting of corrections and retractions, we will no longer be charging additional fees for our Crossmark service. This change applies to all Crossmark metadata registered from 1 January 2020. All members are now encouraged to add Crossmark metadata and add the Crossmark button and pop-up box to their publications - and you can do so as part of your regular content registration.
Richer metadata gives important context
We know that there are many more corrections and retractions that are not yet being registered, and to address this, we are now asking all of our members to start registering metadata for significant updates to your publications, even if you don’t implement the Crossmark button and pop-up box on your content. Remember, anyone can access the Crossmark metadata through our public REST API, and start using it straight away - even if you’re not ready to implement the Crossmark button.
Check out how to get started; if you only want to deposit metadata, follow steps one through four. If you also want to add the Crossmark button and pop-up box to your web pages/PDFs so that readers can easily see when content has changed, then also follow the rest of the steps.
Crossmark
We launched Crossmark in 2012 to raise awareness of these critical changes, by asking Crossref members to:
help readers find out about the changes by placing a Crossmark button and pop-up box (which is consistent across all members making it recognizable to readers) on your landing pages and in PDFs
Members can also use Crossmark to register additional metadata about content, giving further context and background for the reader. These metadata appear in the “More Information” section of the Crossmark box. 7 million DOIs have some additional metadata, the most common being copyright statements, publication history, and peer review methods.
Anyone can access the Crossmark metadata through our public REST API, providing a myriad of opportunities for integration with other systems, and analysis of changes to the scholarly record.
Who has implemented Crossmark?
440 Crossref members have implemented Crossmark to date. 11.4 million DOIs have some Crossmark metadata.
Total DOIs
DOIs with Crossmark metadata
%
Journal articles
80,862,460
10,155,340
12.56%
Book chapters
14,040,646
792,953
5.65%
Conference Papers
6,175,733
457,237
7.40%
Datasets
1,862,852
19,206
1.03%
Books
753,298
239
0.03%
Monographs
469,333
23
0.00%
Of those, about 130,000 contain an update:
You can see which members or journals have implemented Crossmark by viewing the relevant Crossref Participation Report.
