September 28, 2012
First, I would like to applaud the far more proactive actions recently undertaken by the SEC to address illegal manipulative high frequency trading tactics in the US stock market.
The introduction of Reg NMS into stock market governance has been an unfortunate wrong-turn because of the highly complex unintended consequences of imposing restrictions that only work properly and fairly in a theoretical world without latencies. Futures markets around the world, including in the US, are remarkably simple relative to our equity markets.
We should look to the futures market template for guidance as we strive for simplicity, transparency, and above all, fairness, in our stock markets. There are approximately 1000 different order types in the US equity markets. That number should be dramatically reduced, and the remaining orders should be described as clearly as possible, complete with well-vetted examples.
In addition, limit orders that are cancelled virtually immediately are more manipulative than liquidity-providing. I (along with many others) suggest that a minimum limit order lifetime of 50 milliseconds be very seriously considered.