There are additional standard special security groups for SharePoint Online:
Company administrators include any user who is a global administrator for Office 365. By default, the Office 365 Company Administrators group is added to the SharePoint Owners group and the list of site collection administrators and thus has Full Control privileges. Be cautious about changing the group membership for company administrators or removing any of these special high-level groups. As an example, if you remove a company administrator from the SharePoint Owners group, you...
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