files with no copyright holder?

What am I supposed to think of the copyright status of files like
contrib/server-side/obliterate.py? It has no copyright statement nor
license grant. Since it is in contrib, I cannot assume the "default"
copyright holder or license grant used in the rest of the project. Or
can I?

There are quite a few files in contrib like this. In my opinion, you
should adopt a policy of rejecting files from contrib which do not
include a copyright notice and license grant. If these be "CollabNet"
and/or "same license as rest of the Project", fine, but I don't see how
we can assume, at present, that this is what all the authors intended.