It is kind of odd that the approval news was not well received but an upgrade from an anal-lyst is.
It's all about momentum plays for WS nowadays. If Monday's run up wasn't due to short covering then yes the MM's may decide to punish the shorts if this reverses from this point on.
approval news was well rec'd; ;that's why the stock was raped; caught everyone by surprise with the approval, big boys wanted in at the ground floor so they literally raped the stock to bring it down to exactly where it was pre-approval
your smoking gun is a 661k block at $6.61 that i saw cross the tape on wed and there was another 250k block in the low 6.60's that crossed yesterday
once the boys got in, zacks very conveniently upgraded