I'm pretty sure Klingon and most other languages made for fictional universes are copyrighted (or at least many of their creators claim copyright). Let's call these 'fictional languages' in order not to confuse them with languages like Esperanto which were made specifically for people to use them (and not just made to make fictional races seem more real).
These links seem to confirm the copyright situation for Klingon at least:
http://www.corante.com/importance/archives/002300.html
http://higbee.cots.net/~holtej/klingon/faq.htm#2.12
I could not find anything about this on StarTrek.com though and it does seem a bit dubious to copyright fictional words. But then, I'm not sure if we would want to be in a postion to pay legal fees to test Paramount's purported claim (not to mention all the lost effort in a Klingon encyclopedia if we decided to just pull the plug).
Also, the word 'Klingon' is a Paramount trademark.
I'm also uncomfortable with people using Wikimedia resources and the very significant promotional aspects of the Wikipedia name to construct their own languages. Erik's comparison with micronations seems to be an apt one to me (although I don't agree with his specific recommendations since they would exclude dead and many moribund languages).
So, IMO, a language must exist independent of Wikipedia and not be hindered by a claim of copyright before an encyclopedia is started in it.
-- Daniel Mayer (aka mav)
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