The ability to look at comparable but not necessarily identical trades/orders is essential to having any valuable reference source to compare best execution or market manipulation in OTC markets generally. This is hard enough for infrequently traded fixed income instruments, but even more so for commodities trades where location, quality, delivery periods, seasonality and variation in units of measure all complicate the task of identifying and comparing similar trades.
See here for a useful and short video on Tabb Forum on the OTC surveillance capabilities provided by NASDAQ Smarts.
I have spoken with several market participants who are custom-building their surveillance capability because the packaged software vendors have not yet reached a maturity and scope that adds enough value to the specific customer. This missing value can take several forms, e.g. gaps in market/product coverage, gaps in detection algorithms, lack of consistency between voice, trade, email, messaging surveillance solutions.
Nonetheless it is clear that the vendors and venues are not standing still, and there is still a real build/buy choice facing many participants, and plenty of room for innovation in detection approaches.