If you move a shared folder inside of another shared folder—perhaps while organizing your Dropbox—the folder will change locations and break any shared links. Shared folders cannot be "nested" within another folder, and this action will register that you have opted to leave the shared folder. Moving a shared folder into another folder means you will no longer see changes collaborators make to files within that folder. However, this nesting does not affect other users.
https://www.dropbox.com/en/help/64