As we finish celebrating our 25th anniversary, we can look back on a truly transformational year, defined by the successful delivery of several long-planned, foundational projects—as well as updates to our teams, services, and fees—that position Crossref for success over the next quarter century as essential open scholarly infrastructure. In our update at the end of 2024, we highlighted that we had restructured our leadership team and paused some projects. The changes made in 2024 positioned us for a year of getting things done in 2025. We launched cross-functional programs, modernised our systems, strengthened connections with our growing global community, and streamlined a bunch of technical and business operations while continuing to grow our staff, members, content, relationships, and community connections.
Crossref turned twenty-five this year, and our 2025 Annual Meeting became more than a celebration—it was a shared moment to reflect on how far open scholarly infrastructure has come and where we, as a community, are heading next.
Over two days in October, hundreds of participants joined online and in local satellite meetings in Madrid, Nairobi, Medan, Bogotá, Washington D.C., and London––a reminder that our community spans the globe. The meetings offered updates, community highlights, and a look at what’s ahead for our shared metadata network––including plans to connect funders, platforms, and AI tools across the global research ecosystem.
In my latest conversations with research funders, I talked with Hannah Hope, Open Research Lead at Wellcome, and Melissa Harrison, Team Leader of Literature Services at Europe PMC. Wellcome and Europe PMC are working together to realise the potential of funding metadata and the Crossref Grant Linking System for, among other things, programmatic grantee reporting. In this blog, we explore how this partnership works and how the Crossref Grant Linking System is supporting Wellcome in realising their Open Science vision.
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.
Typically, when an editorially significant update is made to a document, the publisher will not modify the original document, but will instead issue a separate document (such as a correction or retraction notice) which explains the change. This separate document will have a different DOI from the document that it corrects and will therefore have different metadata. This process is complementary to versioning.
In this example, article A (with the DOI 10.5555/12345678) is eventually retracted by a retraction notice RN (with the DOI 10.5555/24242424x). Each document has Crossmark metadata, but the fact that RN updates article A is only recorded in the RN’s Crossmark deposit. The Crossmark internal API has to tie the two documents together and indicate in metadata of the original document (A), that it has been updated_by the second document (RN).
The Crossmark part of the metadata schema is used to register updates, but this doesn’t mean that you need to have implemented other parts of Crossmark to deposit updates. In the examples below, in the <crossmark> section you can use only the <update> field in the deposit XML if you don’t usually deposit other Crossmark metadata.
Example 1: simple retraction
This is a simple example of article A being retracted by a retraction notice RN where both A and RN have Crossmark metadata deposited.
First, the PDF is produced and the XML deposited to Crossref.
This is a simple example of article B being corrected by a correction notice CN where both B and CN have Crossmark metadata deposited. The only real difference between this and the previous example is that we are creating a different kind of update.
When a member does not issue a separate update/correction/retraction notice and instead just makes the change to the document (without changing its DOI either), this is called an in-situ update. In-situ updates or corrections are not recommended because they tend to obscure the scholarly record. How do you tell what the differences are between what you downloaded and the update? How do you differentiate them when citing them (remember, we are only talking about “significant updates” here)? However, some members need to support in-situ updates, and this is how they can be supported.
Example 4: correction of article that has no Crossmark metadata deposited
If you deposit Crossmark metadata for a retraction or and update notice which, in turn, points at an article that does not have Crossmark metadata assigned to it, we will generate a “stub” Crossmark for the item being updated. The stub metadata will simply copy essential Crossmark metadata. This metadata can be queried via our API, but won’t activate anything on your site unless you add the Crossmark widget to the corresponding page of the item being updated.
Example 5: correction notice that corrected multiple documents
Sometimes members issue correction or clarification notices which provide corrections for multiple documents. This too can be supported by Crossmark. In the following example, one correction/clarification document provides updates to two documents (F and G)