An Azure service that is used to implement corporate governance and standards at scale for Azure resources.
Azure Policy cannot block the creation of a subscription if mandatory tags are missing. It can only mark the subscription as non-compliant if the required tags are not present, but it does not have the ability to prevent the creation of the subscription.
https://learn.microsoft.com/en-us/azure/azure-resource-manager/management/tag-policies#policy-definitions
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