Reader Extensions is a service of Adobe Experience Manager Forms (previously known as LiveCycle Reader Extensions) that is used to extend the functionality of Adobe Reader with additional usage rights. The service adds usage rights to a PDF document and activates features that are not usually available when a PDF document is opened using Adobe Acrobat Reader DC, such as adding comments to a document, filling forms, and saving the document.
When a PDF is Reader Extended, a digital certificate/credential allows users to interact with a PDF in the free Acrobat Adobe Reader DC as if they have a copy of Acrobat Professional DC. This allows users to perform operations like saving the data entered into a fillable PDF form.
This certificate/credential has an expiry date of January 7, 2023. When a user attempts to open a PDF with an expired certificate/credential, they will receive the following error: