Data Loss Prevention works to identify sensitive information held within OneDrive, SharePoint and other O365 applications such as OneNote.

When attempting to share files and information within these applications through the native O365 functionality, DLP will check and flag if sensitive information is identified. The classifications are listed below

• Credit Card Number
• SWIFT Code
• US/UK Passport Number
• UK National Insurance Number
• UK National Health Service Number
• UK Electoral Roll Number
• UK Driver’s License Number

When you save files to OneDrive or SharePoint with sensitive information you will get an email with the following information as an example:

This item is protected by a policy in your organisation.  Detected issues from data loss prevention:

Item is shared with people in your organisation

Item contains the following information: UK National Health Service Number

These prompts are genuine and due to the Data Loss Prevention Policy, please see the Data Loss Prevention Guidance – NHSmail Support for more information.