Takeover? Bitcoin will always be open source, because it is now licensed using the MIT license. This means you can take the code and do pretty much everything with it. Everyone can therefore grab always use and add to it. It’s something SOME (I am not talking about anyone in this forum) GPL advocates forget sometimes. I did so multiple times 😛 You can’t somehow take it away.
Rearing IP. I don’t know too much about it, but isn’t it somehow free, because there is no patent or something similar yet? As I said I have only minimal knowledge on this topic.