Sounds like exactly what's happening over here at NK. They lost their sweetheart of a merger and rather than accept the new reality and regroup, they're taking their ball and going home.
If anything, I read the stock sell as a sign of the NK-B6 merger eventually succeeding. CEO's know more than we do and there's no way anyone would sell all that stock if they thought NK-B6 would fail and NK-F9 merger would be back on.
Just my $.02. Of course I know nothing.