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If you want to use the auto-label option to tag documents in your organization, you need to have an active Microsoft 365 license that offers the benefit of automatically applying sensitivity labels. This means that all users who will be working with the auto-labeling feature will need to have the appropriate license.
However, if you only want to use the out-of-the-box sensitivity types to create labels and not use the auto-label option, then you may not need to upgrade all licenses to Enterprise 5. You can create sensitivity labels in the Microsoft 365 compliance portal and apply them manually to your documents.
If your requirement is to use sensitivity labels in the Microsoft Purview Data Map, you'll need at least one Microsoft 365 license/account within the same Azure Active Directory (Azure AD) tenant as your Microsoft Purview account.
If your organization has multiple Microsoft Purview Data Map accounts within an Azure AD tenant, then when you extend sensitivity labels to the Microsoft Purview Data Map, those labels are extended to all the accounts in your tenant.
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