@Per Johnsen Thanks for using Microsoft Q&A !!
No, registering Apple Business Manager as Enterprise Application in Azure AD doesn't mean an enterprise version of Azure AD. In Azure AD Enterprise applications blade on Azure portal you can view applications available in your Azure AD directory or tenant including any published application by different companies like Salesforce, ServiceNow etc.
Apple Business Manager is also available for automatic user provisioning under this blade. You need to configure your Apple Business Manager application to make Azure AD provisions your users. Please refer to Tutorial: Configure Apple Business Manager for automatic user provisioning documentation which will help you to onboard your Apple Business Manager to Azure AD. Please let me know if you have any other questions.
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