I stopped using Bitcoin7.com when i had a closer look on my fullfilled orders. They don't match you with the best bid/offer but give you worse prices if you didn't specify it accordingly. To explain it a bit better, find attached my mail I wrote on the 24th of July to them. So far I'm still waiting for a knowledgeable reply which is more than "my help manual suggests...". Asked three times about the issue, only got a little reply as quoted below my request. It seems horribly tough for the devs to answer how their algorhithm works. *lol*
Dear Sir or Madam,
I'm trading with Bitcoins on your account. However, I am curently
considering whether I want to continue this. The reason is that I have
trouble with your algorhithm for matching order/deciding on prices.
As I do not want to put in 3 orders when selling 10 BTC, I usually put
in an order at a low price so that it gets completely filled. ALL
professional exchanges (I work as a trader in real life) work that way
that they match you with the best existing bids/offers. For instance,
the order book looks like:
bids: 5@10; 5 @11 asks: 5@12, 5@13
I enter an order to sell 10 BTC @ 9. I would then get 11EUR for 5 BTC
and 10 EUR for 5BTC.
What happened though, is that I sold my BTC at 9 EUR. At that time there
were clearly bids above my order.
I checked another example, today, where I bought 0.1 BTC @ 10 EUR. I got
exactly 10 EUR, even though there were cheaper asks.
Attached the example trades: (I also have screenshots of the buy trade
showing what happened)
Trade Buy 0.09943 1.00 EUR 10.00 EUR 0.00057 BTC 0.57% 2011-07-24 14:44:14
Trade Sell 0.1 0.89 EUR 9.00 EUR 0.01 EUR 0.57% 2011-07-24 11:58:50
Trade Sell 5 44.74 EUR 9.00 EUR 0.26 EUR 0.57% 2011-07-24 10:57:17
Based on this background I would like to understand, how your matching
algorhithm works. As I could see, the best bid/offer got reduced
accordingly, when I hit it.
Does the person that I hit get the amount I pay (e.g. gets better than
what they asked for), i.e. it is more beneficial to put in an order as
you might get executed at a better rate or do you take the money in your
Thanks a lot in advance for your answer,
From their reply it sounds like the money/BTC you pay too much does not end up at your counterparty:
> I have to admit that I still don't have a ready answer for you.
> From my help manual I can confirm that a buying order (money for BTC) can not be executed with a higher price (an offer for 13.00 can not execute for 13.01),
> but I don't have exact information what happens if this offer covers a lower one (an offer for 13.00 matched with 12.99). I know for sure that during our promo period
> we gave back all money + fees back to the users (excluding the BTC fee) as promotion.
> I have to receive feedback from our development and confirm back to you.
So, what happens with the money? It stays directly at Bitcoin7.com? Neat
From my point of view, I would consider that as legal scamming... I guess I'm done wiht Bitcoin7.com