You are correct. There is no way to know. But these shares are coming from somewhere. The 13F/Gs have started to trickle in. Institutions have sold but many still have significant positions. The beginning-of-the-month spikes suggests leak-out selling, IMO.
The Marley guys are extremely wealthy. They lost a lot of money on Marley but, in the big picture, the loss was peanuts for them. That's why I expected them to wait for the buyout. Plus, it allowed them to keep tabs on the Marley name, which is of substantial value to them. Guess not.
But the sheer size of the selling. It's seems too much for 440K shares per month. I saw a 100K bid put up today. The last 85K or so got eaten late in the day. If it were "only" 440K shares per month, I don't think a MM would want to keep pounding the BID like they are now. They just sold damn near 25% of their monthly allotment in one day. If they had only 440K shares to sell, they're doing a disservice to their client.
The only reason to keep selling like that is because they have so many shares, they don't have much choice if they want to stay on schedule.