CCIE is trademarked in the US. Given it's popularity in India, I wouldn't be surprised if it's trademarked there as well.
That being said, it looks to me like there are lots of websites using this as part of their domain and Cisco must well be aware of them and isn't doing anything.
Still, people will be hesitant to pay much for a domain that there is always going to be a risk of losing, so I don't think that you'd get more than low $xx for it at the wholesale level.