It's taken quite a bit of thought on my side to
think of a response for everything. I never like
stepping on toes, so I try to be careful of how
I word things. But I'm kinda... perturbed by the
fact that Yann (who is usually very quiet) has
been the most outspoken on this subject
(admittedly, I don't know quite why I'm
perturbed. Maybe that disturbs me even more).
Yes, reproducing ANY artwork (be it cels,
Superman or Tony the Tiger) that is
copyrighted/trademarked is quite illegal. I
don't know squat about photographs, so I'm
staying FAR away from that (*tips hat to Yann*)
But also reproducing any character that is
copyrighted to someone else is also quite
illegal, even IF you drew it. This is why you
don't find many pictures containing Goofy,
Donald, Mickey, etc. if you try to look for
Kingdom Hearts fanart. Disney is notorious for
clamping down on such things, as is Warner Bros.
(yes, I speak from experience on this part).
You can argue out the ying yang over how it
could only help companies with free promotion,
but y'know... some companies are just like that.
As for the original question: Do you mind if
your cel was copied?
Personally, no. I'd probably email them and
gently tell them that you'd appreciate them
asking next time. Ultimately, what can you do?
Nothing. You don't hold the copyright. You could
write to the copyright holders, but given their
stance on "fanart"/doujinshi items in Japan (I'm
assuming it was an anime cel that was copied),
they probably won't give a rat's patootie.
The real question is: Do you really care? Does
it bother you THAT much? If it does, why not be
honest to the seller and express your concerns?
Nothing ventured, nothing gained.
Oh! To Yann (or anyone really), feel free to rip
my response apart to shreds. I'm no expert on
such things, and you being a business man,
probably have a much better grasp on the law
than I ever will. ~_^ Most likely, I'll just
say "Hm... I didn't know that. Learn something
new every day." and leave it at that. ^_^