Files, data, and even information about your files, is encrypted with your password before it leaves your computer. It is protected over SSL in-transit, and stored on our servers in its encrypted state.
Your password is never transmitted to or stored on our servers. Without your password, our system's design makes it impossible for us or any third party to decrypt anything you store on our servers.
Filenames, size, and file creation dates are examples of meta-data – information about information. In our design we have access to none of it. To us, your files are simply containers of encrypted data.