The Safe Documents feature is only available to users with the Microsoft 365 E5 or Microsoft 365 E5 Security licenses (not included in Microsoft Defender for Office 365 plans).To learn more, see Feature availability across Microsoft Defender for Office 365 plans. Microsoft Defender for Office 365 Plan 1 and Microsoft Defender for Office 365 Plan 2 are each available as an add-on for certain subscriptions.Microsoft Defender for Office 365 Plan 1 is included in Microsoft 365 Business Premium.Microsoft Defender for Office 365 Plan 2 is included in Office 365 E5, Office 365 A5, Microsoft 365 E5 Security, and Microsoft 365 E5.I did find that, but nothing is mentioning E3: Exchange and SharePoint are domain versions only. This compatibility with Office does not include the Office 365 F3 plans. Office 365 E3 is a cloud-based suite of productivity apps and services with information protection and compliance capabilities included. Previous versions of Office, such as Office 2010 and Office 2007 may work with Microsoft 365 with reduced functionality. I'm doing some research on MS documentation to find if I have the features of Microsoft Defender for Office 365 Plan 1 in my E3 license (Ex: Safe Links) This plan works with Office 2021, Office 2019, Office 2016, Office 2013, and Office 2011 for Mac.