With 50% institutional sponsorship at this point (and about 40% of those holders having acquired their stakes - like FMR - in the low single digits) there is no, absolutely NO, possible scenario I could see in which shareholders would reject a $15/offer (assuming it's made below $10). If, say, for instance, ARIA is trading at $12, and someone offered $15/share, there would be a battle for sure (I would imagine).
At this point, the vast majority of shares accumulated at much higher levels, are retail, and shareholders who are in painful losing positions. If there is anyone who bought this stock at $30 +, and are hoping for a buyout or to be made "whole" on their investment - GOOD LUCK!! It's not going to happen. For anyone who bought at $30 +, at that time, this company was entirely capitalized much differently, to the tune of about roughly 100 million shares less than there are today (ie. at $65 per share, the company was probably valued somewhere around it's valuation today at $4.25)....
Hope those people have averaged down in immensely.