Hi bowlegtroy - ICEBERG ORDERS
Iceberg orders are orders Market Makers execute that are hidden from the level 2 data. However, they MUST enter the order into the level 3, which is basically the 'processing center' for all market orders.
So a Market Maker can enter an order for 10,000,000 shares, but only have the order look like 100 shares in the level 2. This is why it is like an iceberg, because only the tip of the order is showing.
However, in the level 3, where the order is processed, you can see the entire order. All 10 million shares.
Why do they do this? They do it to hide strength and weakness in a stock so that they can take a position. It basically makes level 2 useless, because retail orders account for most level 2 data.
Have you ever noticed that a stock will have 400 on the ask, and millions of shares are traded at the ask, but that number '400' remains. That is because it is an iceberg sell-order ... invisible to most market participants.
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