Some of Wall Street 's biggest banks are executing end - of - day equity trades off - exchange , matching prices in - house and bypassing closing auctions . The number of closing - price trades executed with “ guaranteed close ” by broker - dealers like Goldman Sachs increased from 16 % to 32 % between 2015 and 2017 , according to analysts . The move , fueled by exchange rates increasing fees , has gained popularity as index trackers forecast a surge in end - of - day volumes , but raises concerns over transparency and closing price formation . Last year , closing auctions in S&P 500 stocks accounted for 8 % of total volumes , a near four - fold increase since 2004 , according to Credit Suisse .
Some of Wall Street's biggest banks are executing end-of-day equity trades off-exchange, matching orders in-house and bypassing closing auctions. The number of closing-price trades executed with “guaranteed close” by broker-dealers like Goldman Sachs increased from 16% to 32% between 2015 and 2017, according to Virtu. The move, prompted by exchange operators increasing fees, has gained popularity as index trackers created a surge in end-of-day volumes, but raises questions over transparency and closing price formation. Last year, closing auctions in S&P 500 stocks accounted for 8% of total volumes, a near four-fold increase since 2004, according to Credit Suisse.