There is such a thing as over-sharing and Delve appears to be doing just that. Random cross-checks at a very large client revealed very sensitive documents being shared in Delve that really should not have been, like payslips, performance reviews and bank transfers from people’s emails and C-drives. (For the benefit of SharePoint on-premise clients, Delve is the Office 365 version of My Sites).
The good news is that you can hide your documents from being displayed. Go to the Settings button on the top right, and click on Feature Settings.
Then turn the Documents to “Off”.
Problem solved until you can lock down your content properly on Outlook, SharePoint and OneDrive. With this setting active, you won’t be able to see other people’s documents either, but that’s what SharePoint is for. Right tool for the right job and all.