A system failure at Blue Ocean, a U.S. alternative trading system (ATS), disrupted real-time quotes for daytime trading of U.S. stocks at major South Korean brokerages. Orders and executions through other ATS platforms are proceeding normally, but investors face inconvenience because real-time prices are difficult to check.
The system failure occurred at Blue Ocean around noon on the 21st, halting or delaying real-time quotes for daytime trading of U.S. stocks on the mobile trading systems (MTS) and home trading systems (HTS) of a significant number of Korean brokerages, according to the financial investment industry.
The impact spread widely because many Korean brokerages source daytime trading quote data from Blue Ocean alone. Orders, however, can be processed through multiple local ATS platforms besides Blue Ocean, so trading remains possible.
Toss Securities and Meritz Securities, which have diversified their quote supply channels, are providing quote services normally. Since the 30th of last month, Toss Securities has offered combined quotes aggregating bids and offers from two ATS platforms, Blue Ocean and Bruce, across all U.S. stocks available for daytime trading. The brokerage has maintained its quote service after the outage by using bids and offers from Bruce.
Brokerages notified clients of the suspension and delays in quote data and urged them to check their order records. They specifically advised that unfilled orders sent to Blue Ocean may be canceled en masse. Quote services are expected to return to normal from the U.S. pre-market session on the same day.