Hi Aaron

Thanks for your post. If you share a sub-folder or folder with an external user that user will have access to all of that folder's contents as you specified. That user will not by default have access to the parent folder and/or other non-child folders. If you want to share those other non-child folders with the external user you will need to do that separately. 

Thanks. One further question. Can we provide access to the subfolder in that example and then remove access to child folders? I assume not based on your previous answer but it's worth asking

Hi there

Thanks for your response. When you share a folder the user receiving the shared permissions will be able to access all folders/documents contained within that folder. There is not a way to remove the access of child folders when the entire parent folder is shared.