I'm guessing the seller screwed up. They entered a market order to sell a chunk of stock -- 400k, 500k, whatever -- and in the blink of an eye the buy orders at $0.25 filled, then the buy orders at $0.24 filled, then the buy orders at $0.23 filled, and so on until $0.18 or the price where the buyers balanced out the seller(s). Then the stock moved back up to settle where it did. We've seen this several times on the buy side when the price spikes up on a burst of activity only to settle back down. We shake our heads and whisper, "poor bastard entered a market order."
The seller is the one who feels like they got screwed. The left money on the table.
I don't follow what people are saying about being stopped out. It makes no sense to me. Even if you wanted to, who is able to enter those for IPIX? I'm not. I get the following message when I try to enter a hidden or trailing stop:
Non-equity, bulletin board, pink sheet and other specific securities are not eligible for the type of order you have specified.