It obviously depends on how much the ruling is for. But I'd be glad to pay a couple more billion plus the 1.8BB for the entire WMI portfolio. If we're talking in the 6-10BB range-then yes, the stock will take a dip IMO.
But it could still be a good thing for JPM if they have to pay 10BB more if the portfolio is actually worth 20BB. In that case JPM would have to do a "write-up" of their assets and consequently post a one-time gain.
Too many scenarios to discuss but Wall Street loves and rewards clarity and certainty.