The sellers are in fact hurting themselves. Its better to hold and push it higher especially when there is a short position and there is a target. They can in fact hurt their own support level. Serious minded folks don't sell for a few hundred dollars. Only those with a very huge number of shares would this make sense but it still can be risky. In particular if they didn't buy back at close. A huge gap up and orders not getting filled and the no buy kicks in from every broker. Any number of things. People take their chances with the outcome.
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