ICE US just fined a company $37.5K for having an ATS that violated Rule 4.02 and required them to cease violating Rule 4.02 and also Rule 401. What is an ATS? It is any system that can enter or cancel an order on an exchange without human intervention based on programmed logic. What is rule 402 you ask? It is the disruptive trading practices section. The Rule 401 violation came because of the wording of 4.01:
"Every Person shall diligently supervise the Exchange-related activities of such Person's employees and agents. For purposes of this Rule, the term “agent” includes any Exchange-related activities associated with automated trading systems that generate, submit and/or cancel messages without human intervention. Every Person shall also be responsible for the acts and omissions of such employees and agents." (my emphasis).
Therefore, if a trader builds a model that automatically triggers trade orders, there is strict liability for supervision of the algorithm's logic. This means that you have an obligation to test the logic of your algorithms to make sure they don't violate disruptive trading rules. For example, if you have an algo that has logic cancelling bids anytime the market offer gets within a certain value of that bid or when the bid stack between that bid and the market bid, you may have an issue with potential disruptive trading - read spoofing.
DCM staff have observed that major firms have adopted an internal compliance structure for annual review of all automated trading systems -have you done something like that?