AH looks bad.
everything was down ..it will pass . ah means nothing.
any idea about the agreement with Roche re: milestone payments ? recently an announcement was almost a non event. approx 1 month later, a $10M and a nice pop in price.
If you are worried that somebody bought some shares a little lower on a generally down day of an excellent company with a bright future you have not done enough DD...or are in the wrong arena.