The "Shared With" column displays users who no longer have access to a document in SharePoint Online
Consider the following scenario.
In a SharePoint Online library, you add the Shared With column to the view for the library.
You share a document with a user or group, and the user or group is then displayed in the Shared With column.
You remove the permissions for the user or group with whom you previously shared the document. However, the user or group is still displayed in the Shared With column.
This is a known issue. The Shared with column may display any accounts with whom the document was previously shared before automatic updating of this column was disabled. However, the contents of the column will not be automatically added to nor cleaned up in future versions of the software.
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