Yes, final sign-off on these deals can be a slow and tortuous process. But it still seems impetuous and somewhat risky to make announcements based on a final sign-of that has not yet happened, no matter how secure your feel in the likely hood of that final sign-off happening. Unless, of course a separate agreement was made that if the deal did fall through at that late stage the halting party would compensate the other in some meaningful way.

I think that kind of multi-stage deal is common in large corporate transactions.