After watching this and the DPReview saga, there is only one takeaway:
Don't sell your company unless you are prepared to walk away and do something else - because at some point you're going to be forced to do so whether you want to or not.
Or do exactly what Nate Silver did – negotiate the contract in such a way that you still have control over your IP if they decide to terminate you or sunset your product. Of course chances are that you don't have the kind of leverage that he did, but still...worth a shot.
Don't sell your company unless you are prepared to walk away and do something else - because at some point you're going to be forced to do so whether you want to or not.