ARCA & INET partial/odd lot fills.

Discussion in 'Order Execution' started by mcr, Jun 11, 2007.

  1. mcr


    I'm putting together an order execution system and I'm getting down to a few details.

    I'm sending my listed names to ARCA and otc to INET as round lot limit orders. I should NOT expect to have any partial odd lot fills, correct?

    I.E. I may get 200 of my 300 filled, but never 237. Any help would be greatly appreciated.
  2. B1010


    You will often get odd lot fills on the ecns. Happens to me all the time.
  3. mcr


    thanks for the reply.

    occasionally i'll jump around a bit when sizing my position. so assume I currently want to be 500 long, get filled on 472, change my mind and decide to be 400 long. I'm stuck with an odd lot sell at that point, no way around it, correct?
  4. You could buy 28 shares and then sell a round lot of 100. I don't see how you can be putting together an order execution system until you have greater experience and knowledge with such issues. Just trying to be helpful, not disagreeable.
  5. rayl


    I get small fills on Arca all the time.

    I'm a bit curious as to how they happen bec I thought Arca required a round lot or PRL for all orders but yet I get fills < 100 shares and given how far out of the inside my standing limit orders on these occassions are, I don't think someone else got a part of a PRL cross.
  6. Interactive Brokers will simulate an All-or-None order, which will execute only when there appears to be sufficient contra liquidity to satisfy the entire quantity of your order. This won't solve your particular problem, if you must use resting limit orders to offer liquidity displayed to the market on INET and ARCA.
  7. rayl


    Hmm. I personally rarely use AON but I thought Arca supports AON natively so that your order will be in the book with appropriate priority? I don't know INET as thoroughly.

    Still doesn't give me any clarity on 6 share fills or 17 share fills and the like. Even if someone did a round lot outside the market to test for hidden orders, and I'm getting some residue, these #s seem a bit odd. I don't mind it if not for the $1 min commission on a 4 share fill.
  8. rayl


    Correct that -- Arca supports AON only on options and not equities. My memory was fogged as recently I've been curious about options on Arca and that was the most recent info in my mind.