In pink sheet land of penny stocks, anything goes, and often does. When you see a big move down on a block or big spike up on a block, watch what happens within minutes of those transactions. What happens soon thereafter will be your clue as to whether the trade was legitimate.
Many times with this equity, and all pink sheeters, what will happen is that the same trader will trade to himself. If I am a buyer, and I am looking to buy a lot of shares, I set up one account with X broker, and another with Y broker. I then sell from X broker and buy through Y broker. Since both accounts belong to me, I retain my shares, and create the appearance of panic, hoping someone sees the block go through at a low price and immediately hits the sell button. Of course, if you do hit the sell button the same old guy looking to pick up all the shares he possibly can, is also trading through Z broker and is right there to take those shares off your hands. And all it cost the manipulator is the price of 2 commission trades to see if a panic can be started. There may also be technical analysis reasons for a trader to want to "paint the tape" for reasons known only by the chartists.
I don't mean to imply that the deception is always on the buy side. It could just as easy be accomplished on the sell side, where a trade goes through a penny above the current price in order to induce a rush of buyers to the benefit of a big seller.
What you look for is what happens quickly after those rogue trades. If after a block is dumped low, the bid stays the same or even rises, that's your sign that monkey business in the wild, wild world of the pink sheets is occurring again.
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