Hi @Amty63 ,
You can use $expand
query parameter to get these properties. Please use below Graph API Endpoints:
https://graph.microsoft.com/v1.0/devices?$expand=registeredOwners
https://graph.microsoft.com/v1.0/devices?$expand=registeredUsers
Reference Document:
https://learn.microsoft.com/en-us/graph/api/device-list?view=graph-rest-1.0&tabs=http
Hope this helps.
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