In a theoretical world and under the efficient market theory today's japan approval only increases the intrinsic value of ARIAD if 1 of 2 things are true. 1. There was uncertainty. If there was a lot of uncertainty then it increases it a lot if there was little then it increases it a little. Obvious when said a loud I know. Said differently if the entire japan market was worth 1 dollar and there was a 90% chance of approval then upon approval the value from the japan market would increase from $.90 to $1. In this case I don't think there was much uncertainty so the increase in value should be nominal. The other reason why it could have increased the value is if it happened a head of schedule. If it was expected to be approved a year from now and was suddenly approved today then that would add value to the asset because you will have a longer period of cash flows. However, that is not the case here either. It was approved, as expected, prior to the end of q3.
All in all, I see no reason why the approval from Japan would be a significant driver in the price of ARIAD based solely off approval. Now maybe people are underestimating the Japan market, who knows, but that would not be cured by approval.
