The Document Viewer uses a special web-friendly format which is also encrypted so your documents are copy-protected out of the box. However there are some options in the UI which allows your users to download the original document or replicate it via printing and copying text but you can always disable them when required.
For additional security (DRM) purpose;

- You can disable the "Download" button which allows the user to download the original document. For example, consider you have a DOCX file (e.g. a design template) and you want the user to view this file but you do not want him to download and edit this file.
- You can disable "Download as PDF" button.
- You can disable printing of the displayed document.
- You can disable selecting and copying text in the displayed document.