Sharepoint is a web-based file management system. For this reason it is best to use web policies based on the server URL, which will tag files coming from the Sharepoint server and allow applying of policies in the same way as when using DLP with standard applications.
Sensitive information is stored on an internal web https://intranet/sales, in the form of contracts in PDF format. We set data tagging, which means that all files downloaded from this URL will be automatically categorized in data category Sales. As a next step, we can apply security policy for working with data belonging to this category.