Everybody that is new to trading sees or hears in a chat or discussion thread about MM's and how they are killing or holding a stock from running etc. Anybody that has spent time in front of a screen with Level 2 trading viewing sees the names of the MM's and is familiar with most of the names. Well, market makers are supposed to facilitate a smooth flow of trading for us traders so that when we want to buy Stock XYZ-they supply us the shares and make the trade happen so we don't have to wait for Joe Schmoe to show up and decide to sell his shares to us. These MM's for short, make their money on the fractional difference per share that we pay and the seller gets or vice versa. They are licensed to do this and for the most part are honest in their efforts.

i found this list in my browsing of the stock info available on the net and thought it would be good for everyone to be familiar with who they are dealing with when trying to buy a stock.
Hope the info helps you somewhat. Some of the info may be a bit dated but is overall pretty accurate. Again, I did not draw up this list-only snagged it for personal use and to share with everyone here. My thanks to whoever put it together originally.
If you learn how to read into Level 2 on the OTCBB & PINK SHEETS it will really enhance your trading. Let's break down the Market Markets.
There are 4 categories of Market Makers let's start by talking about the first one.
Retail Market Makers:
These are the market makers from very popular brokerage firms. They handle a lot of the order flow for small retail investors.
NITE: NITE
UBSS: Schwab
SBSH: Citibank
ETRD: ETRADE
BOFA: Bank of America
Second Category: This is the list that you really have to master because these are the MARKET MAKERS that can kill a stock in a hurry when they are the sitting on right side of the box on Level 2.
HDSN: killed CKYS single-handedly
VFIN:
CGFL: new kid on the block for sub dilution
RBCM: Old CLYP. Has killed many sub penny stocks in the past to no-bid.
FANC: used to be a heavy S-8 seller. May show up once in a great while.
SSGI: aggressive on sub penny stocks
Third category: There are lot market makers in this category so I will break it down to who are the most important: These are some of the more friendlier market makers on the street.
DOMS: one of my favorites
MAXM:
VERT:
HILL:
SALI: can be a seller at times
JEFF:
FRAN: very friendly
ABLE:
QUIN: haven't seen him around much lately
VNDM:
SEAB:
MURF: getting active lately
STGI: getting active lately
VERT:
WDCO: can be a seller at times
PERT:
NIII:
BEST:
GNLN: nice to see him back again
EFGI: can be a seller at times
Category 4: ECN MARKET MAKERS: Electronic Routes
these market makers are only used on OTC BB stocks. They do not work for pink sheet market.
ARCA: used a lot by promoters to sell stock
TRAC: rarely used any more taken over by EDGX
EDGX: new kid on the block
There are probably a few market makers that I left out or there will a few new market makers that show but for the most part these are the major players. Good luck hopes this helps.