It's a manipulation tactic to scare people into selling, if that same seller is the buyer below probably, think about it, if you sit on the ask with 509k, 50k share holders get nervous and sell, then in a separate account you sit on the bid below for 30k making it look like it's bad, when the reality is if some one who was a whale just rolled up and bought all 509k that person would be pissed and panic and try to take the ask down.
I've seen it before icbu is being accumulated.
Shark.
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