Zev Maybe Frost sells the shares to keep PLX price low so his company Teva can make an offer to buy PLX at a lower price. Pfizer owns Uplyso 60 percent outside Israel but PLX partners with Teva for the platform and future drugs.
I think that the decline in PLX PPS has a lot to do with Dr. Frost continued massive sale of his PLX shares. What worries me is that, out of revenge, he may continue to sell into and even after the FDA ruling regardless of whether it is good or bad just to keep the price down.