I agree, nothing is announced until either it must be announced because a shareholder vote is required, or it's completely finalized, doesn't require a vote, and the finalized terms are being announced.
It's very possible for such an agreement to be created with a triggering event, it could be a specific milestone occurring, like FDA approval, or a financial goal being achieved, say a share price of $15 or more, but nothing is said before it occurs, then suddenly it is announced. That agreement may have occurred months, or even years before the triggering event occurs.
I really don't know if all such agreements require shareholder concurrence. In a BP like Merck I would suspect that they can go to the major Institutions and get such concurrence without a public vote of shareholders, I'm uncertain if L.P. can do the same with major shareholders, though clearly she and others do hold substantial shares.
Gary
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