Personally, if I was a JPM shareholder, I would be more inclined to buy more shares after all the rulings related to WMI just because litigation is becoming a huge expense for them. Getting rid of this case would be a sigh of relief to me even if it meant a one-tiime write-off of a couple billion.
Edit: just looking at the volume, it looks like a hedge fund or some other big institution is dumping shares. I don't have real-time on it but I would assume the stock would close higher from here (@ 43.06/share).