I'm looking for a word that defines that something is out of our control in a business sense. For example, we can't control the postal delivery time, so it is... (out of our control). Needs to be ONE word, please.
EDIT - not uncontrollable. It is also not chaotic, like "the children are out of control".
EDIT2: - to further explain, in my thesis I have a number of dependencies. Most of them our company can control as we manage them. However, a few of these dependencies we are not able to control because they are managed by someone else. So I'm looking to see if there is a word that can explain this other than saying "dependencies that are out of our control".