Blue Ocean expands suspension to 18 securities, disrupting South Korean overnight trading

Aug 31, 2026 06:26 (21d ago)

Blue Ocean suspended trading in 18 securities for South Korean retail investors, mainly leveraged and inverse U.S. products including SOXL, beginning with Monday’s 8 p.m. ET session.
The suspension followed SEC rules limiting an individual ATS to 5% of a security’s average daily trading volume; an earlier report identified four securities subject to overnight quote restrictions.
KRX’s stock after-market remains scheduled from 4 p.m. to 8 p.m. on the 14th, while ETFs and ETNs remain excluded from ordinary connected trading and can use limited block-trading routes.

Blue Ocean, a U.S. alternative trading system, suspended trading in 18 securities used by South Korean retail investors, mainly leveraged and inverse products, beginning with Monday’s 8 p.m. ET session to comply with U.S. Securities and Exchange Commission rules. The newer account expands on an earlier report that Blue Ocean had halted overnight quote dissemination for four securities—SOXL, KORU, SNDU and RAM—after concentrated Korean trading apparently pushed a security’s share of average daily volume above the SEC’s 5% alternative-trading-system limit. Trading through other venues may remain available through limit orders, but without real-time quotes. Separately, South Korea’s Korea Exchange excluded ETFs and ETNs from its planned four-hour weekday stock after-market, creating broker compliance issues and leaving domestic block trading as the principal after-hours alternative.