I have no idea, but it has been around a long time. I was not familiar w/ the supposed 911 signal (or I had forgot) until I saw it yesterday in the box and read some posts on this board. Trades ending in 911 could be random (though I would think most people round their trades), could be MM's sending signals, could be pumpers/flippers trying to gin up momentum or it could be a combination of all of the above.
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