When you share confidential files with others through your work account, it is important to keep track of who has access to the file. This can be checked at any time by following the instructions bellow.
How to Manage Permissions for Files in OneDrive
Locate the file you would like to manage
Click on the vertical ellipsis to view more information
In the drop down bar, click Manage access
To stop sharing with all users, click Stop sharing at the top
To stop sharing with specific users, click on the down arrow next to the list of users with access
Click the X next to the user to remove access
Click Remove to confirm
To share with additional users, click on the Share button and enter their emails
Click Send to confirm