@ajacobson - are you sure? I think OMM can CXR (at lest off the top of my head I can’t think of a reg that would prevent them from doing so). Truth is, they don’t even have to - since they will fill you on the display size (say a 1-lot) and pull the hidden portion. Even the price- improved fills are going to be negatively selected as you would imagine. Ps. Re-read, seems like we are in agreement regarding the quality of the fills Pps. I recall seeing a form that indicates that they primarily sell to Citadel
Electonic OMM pulls a market after an order hits it immediately notifies market reg. I posted their 606 in stocks - gossip is 2 Sigma - surprised not to see SIG, but to your point Citadel makes sense. No question quality is hurt by payment - also a reason payment is not uniform. First payment deals were a % of b/a.