If you run a business, an employee can easily email your client list to their personal account, whether by accident or on purpose.
Most companies just trust their staff not to do this.
But you need a technical rule that stops sensitive data from leaving your network in the first place.
If you use Microsoft 365, you can use a tool called Microsoft Purview to set up Data Loss Prevention rules.
When you turn this on, the system scans every outgoing email, Teams messages, SharePoint/OneDrive files, endpoint devices, browser activity, and Microsoft 365 Copilot prompts before processing.
If it detects sensitive information like Social Security numbers, credit card details, or specific internal company tags, it physically blocks the email.
You do not have to monitor employees manually.
