You are forgetting that come Monday they will announce 4th quarter and year end results. Some people do not like to hold through such announcements and close out their positions. Most of your traders will take profits waiting to see which direction the trend goes next. There were two major announcements this week that should have easily put this in solid $7 range. Some of the trading was related to the IBB index fund, it mirrored it at times.
It will be interesting to see the results come Monday after close.