To check the access history of a file choose Properties from the right-click menu or select Sidebar on the actions bar and choose Properties. When viewing a file, click and then click Properties. Click the Access History tab to see all activity for that file.

The list there shows you when the file was accessed, how the file was accessed (for example, by using a link) and by whom, and what was done, such as download or view. If a public link was used by someone who’s not a member of the folder, the link name is shown.