Thank you for reaching out to us. As I understand you are looking for conditions/scenarios for device to be Azure AD Registered.
The goal of Azure AD registered devices is to provide your users with support for the bring your own device (BYOD) or mobile device scenarios. In these scenarios, user can access your organization's resources using a personal device.
Provisioning
Windows 10 or newer – Settings
iOS/Android – Company Portal or Microsoft Authenticator app
macOS – Company Portal
Key Capabilities of Azure AD registered devices:
SSO to cloud resources.
Conditional Access when enrolled into Intune
Conditional Access via App protection policy
Enables Phone sign in with Microsoft Authenticator app
Reference: https://learn.microsoft.com/en-us/azure/active-directory/devices/concept-azure-ad-register
Let me know if you have any questions.
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