On 17 March 2026, we experienced an outage that affected DOI resolution for Crossref DOIs and the deposit of metadata records by Crossref members. In this summary, we outline what happened, the impact on our community, and the steps we are taking to strengthen our systems and processes as a result.
We’re excited to announce a new data citation API endpoint and are seeking your feedback. The new service makes existing data citation relationships in our metadata available, thereby surfacing this part of the research nexus. At the same time, we’ve decided that it’s time to move on from Event Data.
Metadata is communication; it can tell a story about research and paint a picture for others to respond to and learn from, across the world and throughout the forthcoming generations. Metadata can feel technical with words like ‘infrastructure’ and ‘schema’, and sometimes, like tech in general, it comes with hyperbole. But metadata really is part art (storytelling and pictures) and part science (structured models and standards) with both aspects being equally important, and requiring people as well as systems. That necessary combination of human and machine involvement also makes metadata challenging.
Once a year we release all metadata records for content registered with Crossref in a public data file. This year’s version, containing nearly 180 million records, is now available. It includes metadata associated with all Crossref-registered DOIs in JSON-lines format.
On September 1st we completed the final stage of the Crossmark v2.0 release and sent an email to all participating publishers containing instructions for upgrading. The first phase of v2.0 happened when we changed the design and layout of the Crossmark box back in May of this year. That allowed us to better display the growing set of additional metadata that our members are depositing, and saw the introduction of the Linked Clinical Trials feature.
Now all publishers have the opportunity to complete the upgrade by simply replacing the Crossmark button and the piece of code that calls the box. The new button designs are, we think, a much better fit for most websites, and are designed to look more like a button than a flat logo. The new buttons are also available as .eps files for placement in PDFs.
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Crossmark box on a mobile phone
Most importantly, switching to 2.0 makes the Crossmark box responsive for better display on mobile devices.
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Just two weeks after the code release a number of publishers have already upgraded and are running Crossmark 2.0 on their content. Congrats to the Pan African Medical Journal who were the first member to upgrade just a couple of days after the release. Â Of course we realise that many members will need time to schedule the upgrade, and while we are keen to see as many early adopters as possible, we will support version 1.5 of Crossmark through to the end of March 2017.
If your content is running Crossmark 2.0 we would love to see it. Drop us a line or put a link in the comments below.