Why would the broker themselves even have to know? The point isn't that the shorter and their motives should be disclosed, it's that the long side has plenty o

Why would the broker themselves even have to know? The point isn't that the shorter and their motives should be disclosed, it's that the long side has plenty of explanations for why the short side is short other than simply taking the other side of a risky bet. The Goldman case isn't about whether or not they should have disclosed that the short had speculative motives. It's that they actively lied about who put the reference portfolio together and why.