Joss' creative control over the Buffyverse

[AndrewCrossett]

What is Joss Whedon's exact legal status regarding ownership of the Buffyverse and its characters?

According to copyright notices, 20th Century Fox is the sole owner of the property and its copyrights and trademarks.

Does this mean that Fox would be legally able to shut Joss and/or Mutant Enemy out of his own creation if they wanted to (as suicidal as that would be)? Does he have some sort of contractual legal right to creative control over Buffy and Angel projects?

[Saturn 5]

I was wondering that to, there's at least one unauthorised Buffy webcomic on the internet that charges to view it, I'd love to report that to someone but who exactly?