Crossmark Service: Displaying the Current Status of Content

Crossmark gives readers a cross-platform way to quickly find out the status of a piece of research, along with additional metadata related to the editorial process. Crucially, the Crossmark button can be embedded directly in a PDF, giving members a way to inform readers of changes even months or years after the file has been downloaded.

Benefits of Crossmark

• Members can report updates to readers and display additional metadata.
• Researchers and librarians can easily see changes to content, which license applies, related clinical trials, and more.
• Anyone can access Crossmark metadata through the Crossref REST API (https://api.crossref.org/), enabling integration with other systems and analysis of changes to scholarly records.

How Crossmark Works

Members place the Crossmark button near the title of an item, both on their web pages and within PDF files, and commit to reporting any updates — such as corrections or retractions — to Crossref, while optionally adding metadata about their editorial procedures and practices.

Image Source: https://www.crossref.org/documentation/crossmark/

Obligations for Members Implementing Crossmark

If you implement the Crossmark button, you must:

• Manage your content and promptly register any updates.
• Include the Crossmark button on all digital formats (HTML, PDF, ePub).
• Implement Crossmark using the official script provided.
• Not alter the Crossmark button in any way other than resizing it.

Crossmark should be applied to all new content, not just updated content, since selective application means readers who downloaded an older version will not know that the content has since been updated. Applying Crossmark to previous years' records is optional but still encouraged — particularly for records that have since been updated.

Steps to Participate in Crossmark

• Draft an update policy, assign it a DOI, and register it with Crossref.
• Add the update policy and any other relevant metadata to your metadata records.
• Publish corrections, retractions, or other updates for works that require them, and register the corresponding metadata.
• Implement the Crossmark button both online and in PDF files.

Important note: The presence of a Crossmark button is not an absolute guarantee that a piece of content is always up to date, but it makes it easier for the community to verify how members update their content. There is no additional fee to participate in Crossmark. Organizations that are not responsible for the content can also implement the button, except for the update-reporting obligation.