These are highly tradeable events.
I wish I saw this.
Personally, I think these types of scenarios happen when someone is getting their a$$ handed to them in a lower short position, so they start accumulating a sizeable long position which they can set off, at market, and set off a huge limit order sell flurry.
They lose slightly on the long position (possibly, depending on where they started buying), but their short position is the larger of the two, where they can average into, and close out that position when they raid the stock.
The most obvious display of this crap was with DNDN an hour before they released Provenge data. I am so pissed off about it too, I literally (no pun intended) when to take a bathroom break, came back 5 minutes later, and the stock had moved from 20ish, to 8ish, and back to 18 or so within 5 minutes.
S.E.C. look into it? Nah. They're too busy watching porn on their computers.
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