Prevent creation of personal (unshared) files/folders

I'm intending on using Owncloud as a shared folder tool.

As the admin I have created some root-level folders and then shared each to various read/write or read/only groups.

Is there any way I can prevent users creating their own (unshared) files and folders - so they can just manipulate the shared folders according to the permission their group allows?


Hmm, thinking about it - what if I set each user (except me) a really small quota?

Could they still add/manipulate files in the shared folder. I assume as I'm the folder owner that comes from -my- quota?