When files are uploaded and/or shared, their source (“Manual”, “Task”, “Message”, "Request", or “Multiple”) is listed. This allows you to follow the audit trail. In the process, you'll also be able to see who the file is associated with and the date it was uploaded.
To see an audit trail of a file:
Click on the Files page.
Click on the file you would like to audit
Note that you can see the date added, as well as users who are associated with the file.
Click on the source to see where the file was shared. Clicking Multiple will reveal each place it was shared.
Click on any source to follow the trail.