Does Nintendo have a strangle hold on the PokeMon Company/IP?
Is there no chance one day someone else could decide they want it?
If so would Nintendo be powerless if the PokeMon Company wanted out?
I suppose technically someone could purchase both GameFreak and Creatures Inc and thus have more control over the Pokemon Company and IP than Nintendo. However as both are privately held companies rather than companies traded on the stock market that makes a buyout of those much more difficult. Nintendo likely own a minority share in Creatures Inc and I've heard the same about them owning a minority in GameFreak before as well. I don't know how private companies operate in Japan but here in the UK private companies can have agreements set up which prevent shares from being sold to 3rd parties without full agreement. I doubt it would be much different and if Nintendo do in fact own minority shares in those companies (even one of them would be enough) then I very much expect they would have made sure such an agreement was in place.
So, in short it's impossible to tell for sure, however it's very likely Nintendo have agreements and contracts in place which prevent a change of ownership or direction in the Pokemon company without their approval.
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