I have read a bit about Level 2 and the benefits of seeing the market depth to help you gauge the market. I often indulge in L2 watching, waiting for the "perfect" moment to either get in or out of a stock. I also hope that this is a good time to start this since I will be sitting on the little cash I managed to pull out for a while till the turbulance calms a bit; additionally, hope to get some info from other PIs on how to get the best out of L2.
I have noticed quite a few things (minor they may be but thought I'd air them).
1. When a private investor (O trade) makes a transaction, this is not always reflected as the latest price for some stocks. Only AT trades are, why is this the case?
2. The O trades never alter the order-book; I know in my case it may be because my brokers are MMs, and therefore may be buying from them, but should these shares / securities not be up on the order-book too?
3. Not all trades executed (buys or sells) are streamed in the trades window, is this because the service is not DMA?
4.

sned - interested in your comment "these guys monitor traders" (post12). Is it true that MMs monitor individual traders?? Anyone else any comments ???

Further querries

I am afraid - are Limit orders ranked by price and time on the MMs and market orderbook simultaneously?

e.g If I placed a Limit buy (above image) for 617.00 @ 12:43, will this get executed before the trades placed at 12:44, and if not why?

Sned; Price and time priority. So if you placed an order at 617p at 12.43 you would sit at the top of the buy column so would get filled first, however if you entered a buy order now (3.10pm) at 617 you would sit third in the list

thx Bullshare - and that applies to LIMIT orders too ..?

I think the difference between DMA and using a broker is confusing you Sned. Are you using direct access or buying through barclays stockbrokers?

With Direct access to the order book you place an order and wait to be filled on the buy side @ 617p.

If you're buying through a broker then you will get filled instantly on the sell side if you place an order at 618.5, and will probably get filled just under the price, maybe at 618.3.

If, using your broker, you place a limit order at 617p then you have to wait until the sell side comes down to 617p.

Does this help?

Absolutely. I was confused on that bit. I gave up on limit orders because they rarely got executed; the reason being what you just explained above. thx a lot for your input.

I deal through a broker but am interested in dealing DMA - how can I do this???
Thanks.
JJ.

Interesting article here