I'm no level 2 expert, but something I see constantly in less liquid naz stocks (under 300k per day) is agressive selling by a MM selling essentially an infinite number of shares hidden behind a lower size offer (100 or 1000sh). This aggressive seller keeps offering lower and lower, selling thousands of shares at lower prices, despite there being a good demand for the stock, and lots of buyers taking shares from the MM even as he offers lower prices. Finally the MM "settles" at a price that is very near (or at) an impt support level, and from there continues to sell thousands of shares to eager buyers who [apparently] want to buy at support. Quite often this is followed by a good-sized block on the tape (5,000-20,000 shares - remember the stocks I'm referring to only do a couple hundred thou per day). Today I noticed this scenario play out, and during the selling period, some blocks traded during and shortly after at about a nickel below where the MM was selling. All along, the MM was selling stock from the open until the price started to drop, and then moved lower and kept selling, often at a psychologically important level, such as a whole number. It will often also occur right around an impt support level. Also, there's been no news on the stock, so there's no panic selling or anything like that. So taking these things into consideration, what's the real story? Here's a more detailed scenario - ABC has important support at 20. It's been trading around 21-22 the past couple days, and today it opened at 20.75. As usual, ABC started moving up to 21, where it met a MM selling alot of stock at 21.00, and then the MM moved down and finally got down to 20.05, where he was showing 100sh offered at 20.05, but was hiding size behind it, actually selling thousands of shares. 20 is a very important support level for the stock, and at 20, there are many buyers - ECNs and MMs - lined up to buy. During this time, a few blocks appear on the tape at 20.00. When the MM is done selling, the stock, of course, skyrockets back up to it's normal 21-22 range and it's then business as usual. I'm hoping there is a simple answer for this, but any insight would be huge. Thanks!