80-100K and up, IMO-it doesn't matter..i believe that real purpose is to drive me(the retail guy) out of business.
it's obvious that low volume stocks can be manipulated, but dude, if you don't change the price, you wont be charged extra commission, keep your order sitting where it is... just find a systematical way on how to get rid of these 1 shares for a profit...
Back when I used Datek, I'd sometimes get odd-lot fills for my round-lot orders. My theory was that the other side was trading either a basket of stocks or some round dollar amount (e.g. $10K worth of CSCO).
it's everywhere. specially on low volume,low priced stocks. i doubt that they can be part of someone's basket. specially when you see those executions all day long.
A number of answers for this. Some already stated. 1) If you get filled on 1 share on a hidden order, it is usually an HFT program pinging the various exchanges, or dark pools to map the hidden liquidity. 2) Its also a way for HFT to gauge which orders are real and which orders are other HFT programs. When your 500 share order becomes a 499 share order and stays on the book, it is mapped. 95% of orders, especially on big caps are just fleeting HFT liquidity, so knowing which orders are real and which orders are not is a huge edge. That 1 share tells a big story in the mapping of real liquidity.