Partial Fills in ECNs

Discussion in 'Trading' started by kenstl, Nov 15, 2001.

  1. kenstl



    Does anyone know offhand which ECN's do not permit partial fills (<100 share increments)?

  2. Magna

    Magna Administrator


    Does anyone know offhand which ECN's do not permit partial fills (<100 share increments)?

    I think you might be mixing up two things, partial fills and odd lots. As far as I know all ECN's permit odd lots (<100 share increments), and therefore receiving a partial fill is quite possible. As far as protecting yourself from partial fills, I think only INCA permits AON (All or None) orders, whereas the rest of the ECN's don't accept AON. But I could be wrong on this so I'm interested too.
  3. The best ECN to get odd lot fills is ISLD. The worst ECN for odd lots is INCA. You can initiate odd lots on ISLD and get filled very rapidly, since you can hit a 1000 share order and get your 53 share odd-lot filled. Try using ISLD.

    Gene Weissman
    Lieber & Weissman Sec., L.L.C.
  4. LoneHand


    Your best shot is INCA, I had something like this happened to me before:

    Sell 950 shares on INCA (bid 1000) and got 900 filled... the rest of my order is "live" even inca still have a 100 bid... don't know if the bidder has some kind of "setup" on his software or what...I use inca more now a days even I pay a little more on ECN fees since I trade 1k to 2k most of the times.

    Good Luck
  5. Well Put. INCA is mostly institutional order flow.

    Gene Weissman
  6. kenstl


    yes, i did mean odd lots - i was totally fried after what happened to me this morning when i posted this message. :confused:

    i was doing alot of scalping this morning, and i send most of my limit orders through IB Best Ex. - almost all of these orders are sent to island by IB.

    i was in a scalp, long 200 shares, and selling on the inside offer, and got filled on 108 shares of a $50 stock, leaving me with 92, waving my dick in the wind. as the stock started moving against me and i was no longer on the L2 screen, i put in a Best Ex market order, and watched trades go off for about 90 seconds until i cancelled. i then put in a Best ECN market order, and the same thing happened. finally, i just bought 8 shares at market (which executed right away, in accordance with murphy's law) and was able to dump what was now a 100 share lot.

    i had gotten partial fills on island before, but never in a lot smaller than 25 shares. island is nice, but i'm not risking what happened this morning again.

    what i was getting at was...which ECN wil not accept odd lots, period? INCA accepts FOK orders, but IB does that is not an option.

    after this happened, i programmed an INCA layout into IB for times like this to lower the chances of odd lot fills that i can not get rid of afterward. i mean, who the hell buys 108 shares of a stock??????????????????????????????????????

    i seem to remember reading somewhere that island is the only ECN specifically geared toward odd lots, and that INCA wouldn't take any orders that aren't in 100 share multiples.

    thanks for your help...i'll switch to INCA and see what happens.
  7. INCA is ok, but the ECN is sometimes "slow". ISLD & REDI seem to have the best execution times, with ARCA & INCA somtimes slower. INCA has great order flow in NASDAQ 100 stocks most of the time. I use INCA myself for large cap NASDAQ over 1000 shares like MSFT,DELL CSCO etc..... Good luck.

    Gene Weissman
    Lieber & Weissman Sec., L.L.C.
  8. sallyboy

    sallyboy Guest

    While Island is most often associated with odd lots, Arca is good to use as well because it will execute against odd lots in Arca, Redibook, & Island.
  9. Magna

    Magna Administrator


    Good luck with INCA, but like I said I'm pretty certain that all ECN's accept odd-lot orders. So if someone is buying an odd-lot and you're selling at the inside you always run the risk of a partial fill. Everyone who trades thru ECN's has had partial fills a number of times and, yes, it is unbelievably annoying. I know someone recently who put in a bid for a 500sh lot and was filled with 1 share. Not kidding.
  10. I've actually onces got 2 share fill when shorting RMBS on ISLD.
    Tough to break even with commissions :)
    #10     Nov 15, 2001