Okay, that makes sense. But if there's a buyer for block trades, then there must be a seller, correct? Is this something that shows up on level 2? For a while we have been seeing this big wall appear a few cents above this bid. Because it is usually large, and if someone were to reach up a grab it (providing they aren't playiing games and actually sell it), does this constitue a block trade (i.e. 50,000 shares traded)? Or, are block trades something that the retail investor doesn't even see on the bid/ask and it is traded between the institutions??

Thanks for taking the time to help me understand.