Frankly most of it was pulled from my...need I say more? No, I've picked up bits and pieces and some has assembled into reasonable seeming explanations which may or may not be correct. I also rely on the board to correct me if I'm wrong. Do wish we had a MM experienced poster who could clarify a lot of this stuff for us.
Some of the stuff is obvious, like any MM can jump in and buy at the ask, or for that matter sell at the bid even though they are on the board at a different amount and far back in the pack. Don't know if it's 1st come 1st served in that regard because you have bid/ask coming in from all over the world. The morning lineup? I don't know if they draw straws or what? The other stuff pretty well shows on the Level II screen, time when they came on or changed their bid/ask. etc. Others have discussed MMs have Level III themselves which gives all the details of how many they have to sell, want to buy, who made the trades, etc.
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