http://www.reuters.com/article/2015/09/18/convergex-group-darkpool-idUSL1N11O1CY20150918 "Our clients have indicated that ATS platforms that do not offer unique liquidity and functionality are no longer essential in the marketplace," the note said. Dark pools have faced intense scrutiny in recent months over concerns about the lack of transparency in the trading venues, with several regulators probing how they operate. To boost oversight and investor confidence as more trading has moved away from public exchanges, the Financial Regulatory Authority last year began publishing the volumes of all ATSs. Since then, several low-volume dark pools, including one run by Wells Fargo, have closed.