Both groups want it lower - institutions buying in and short funds wanting to cover. Retail is along for the ride.
However, the game is rapidly approaching a conclusion once significant news is released - one group wins and the other suffers some pain. I think VVUS's latest EU rejection has triggered the covering, as this leaves ARNA with the only ball in the game for the next couple of years. Also, VVUS latest downgrade and lower than expected revenue creates doubt and fear that they are going to continue to struggle without a major partner who can help fund the needed research. JMO