One would assume that among the 7 million +shares short that a significant portion were hedged with long call positions. The July series have already expired. That's when the stock started to move up. The next expiration is in October. At this point it's almost impossible for shorts to hedge, unless they trade the stock (far more difficult to do than with options) because the options exchange only permits closing trades. So with each advancing month that Takeda works on Omontys, the options series begin to evaporate. If we are at the same standstill on the third Friday of October, I would expect the share price to move up smartly (unless there's substantive news on Omontys). The longer the ordeal, the better it is for the longs.