Henry,
I looked into the market makers several weeks ago. Here a rundown: Bear Sterns (24%), Merrill (24%), Raymond James (14%), Mayer & Schweitzer (6.6%), Herzog, Heine (5.5%), Tucker Anthony (4.0%), everybody else (13+ firms), the balance. Bear and Merrill were about equally split between block and retail trades. Raymond James did more block whereas Herzog and Tucker did more retail. Data was for July, before big move, so relative positions may have changed, but the primary MM are still dominant, no doubt. I also looked into major institutional holders, but have mis-laid the information. When I find it, I'll put it up.
BTW, Merril turned over slightly more than 1 Million shares in July, so that gives you some idea of their relative dominance in the market.
Ted |