Who would do dumb computer trading stuff on UOS, of all things?...

Who would do dumb computer trading stuff on UOS, of all things?

I had a sell order in: 10,000 shares at 53. I have a lot of UOS and I'm keeping most of them for the long-term but want a little cash for another purpose. I'm not really keen on selling even a small parcel of this excellent company, so I put them in a fair way above the bid at .53, which would be a new 12-month high. Not fussed if they don't go off.

Anyway, I looked at the depth this morning and saw that there was a second seller, also at .53. Only a very small parcel, $300 worth, and behind me in the queue. So I upped my asking price to .535, which would leave Mr $300 as the lowest ask and the best chance to get a sale (good for him), and make me feel better about selling something I'd really rather keep if mine went off as well.

Well blow me down, the instant I put my amendment in - and I do mean the *instant* - Mr $300 changed his order to come behind mine again at .535 WTF? It was [i]way[/i] too fast for a human reaction, it could only have been a computer. I'm on IRESS, and I'm taking changed order in the time it took IRESS to refresh the market depth (which was already open) after my amendment. How long was that? One second? Around about that.

Weird.