I sent this question to Mytrack and the following is their reply. Thanks for the information.
"So I wonder what would happen on an OCO order if you had a stop for 1000 shares at 13.75 and a sell for 1000 at $15 at got partial fills on both sides?????"
Thank you for selecting myTrack. You should not get a partial fill on both sides because once you get a fill on either side of the order the other order is cancelled. If you have any question feel free to contact us via email or phone 1800-698-7225. Thanks, Dewayne