Google aquires duck.com and points at own search site
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I first inquired about it on 11/4/09. After several attempts, I got back a response "from management" on 3/25/10 that they didn't want to sell it. Understandable.
Now http://www.on2.com/ points to a Google explanation page about the On2 acquisition, yet http://duck.com/ points directly to Google search.
It looks like duck.com changed nameservers from ns1.on2.com to ns1.google.com about a month ago; my guess is that duck.com started pointing to Google as part of the switchover of nameservers from On2 to Google.
I don't know what Google's policy on selling domains is. I don't remember Google ever sell any domains offhand, but I dropped an email to one of our domain people to ask about that.
buying the corporation that owns duck.com for 100+M == classy