SharePoint Online Administrator

Generally speaking, an admin holding this role can override any restrictions you've put in place. Only give that role (or any admin role) to people you fully trust.

If you are interested in protecting specific documents, you can apply a sensitivity label to them and scope the label to exclude the user(s) in question. There are some caveats there too, and you might end up loosing some functionality in your goal to secure access. So it's best to remove the role altogether.

Hi @dasrp,

No, the SharePoint Online Administrators have all access to all contents in your tenant. The SharePoint Online Administrator role has the ability to override any restrictions that have been put in place, so it is important to only assign this role to individuals who are fully trusted.

In your scenario, I suggest you use teams/group admins instead of SharePoint admins. You can create several teams/groups for different companies and add different group/team owners for different companies.

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