Korea Exchange to launch after-market trading Monday, extending session to 8 p.m.

Korea Exchange will launch an after-market session Monday, allowing investors to trade shares in real time even after the regular trading session ends. The four-hour window, running from 4 p.m. to 8 p.m., will cover most Kospi and Kosdaq issues, replacing the existing after-hours single-price trading system.

Korea Exchange said Wednesday that it had approved amendments to the operating rules for the Kospi and Kosdaq markets. The after-market session will run for four hours, from 4 p.m. to 8 p.m., with orders executed in real time. This differs from the previous after-hours single-price trading system, which ran from 4 p.m. to 6 p.m. As a result, Korea Exchange will discontinue that system.

Most Kospi and Kosdaq shares and depositary receipts will be eligible for after-market trading. Exceptions include stocks under investment warning and those undergoing liquidation trading procedures that require closer market oversight. However, Korea Exchange will exclude ETFs and ETNs from after-market trading due to concerns over market volatility.

Only limit orders, best-priority limit orders and best-price limit orders will be allowed. Market orders, whose prices can fluctuate depending on market conditions, will be restricted to protect investors.

The after-market session will apply the same daily price limit as the regular session — plus or minus 30 percent of the previous day's closing price. It will also trigger the same volatility interruption mechanism used during regular trading hours to curb sudden price swings caused by short-term shifts in supply and demand. Settlement of shares traded during the after-market session will occur two business days after the trade, or T+2, the same as in regular trading.

Even after the after-market session begins, disclosure filing hours will remain unchanged, from 7:30 a.m. to 6 p.m. Korea Exchange said most listed companies file disclosures during business hours, and extending the disclosure window could risk delaying the release of negative news.

However, if media reports or other sources reveal embezzlement, breach of trust or other delisting-related issues after the disclosure deadline has passed, the exchange will act. It will suspend trading of the relevant stock as necessary.

"The launch of this after-market session will be a first step toward elevating South Korea's stock market to a global standard by improving investor accessibility and market competitiveness," Korea Exchange said. "The extended trading hours will allow investors to make quicker investment decisions by immediately reflecting information that emerges after the regular session ends into prices."

Securities firms are also rolling out promotional events tied to the after-market launch. Korea Investment & Securities said Sept. 1 that it would mark the launch of Korea Exchange's after-market trading with a promotional event. The brokerage will give the first 3,000 users of its Bankis app a daily 2,000 won ($1.50) investment credit usable during the after-market session, running through Sept. 30. The credit can be claimed once per day during the promotional period, and any unused credit will be automatically forfeited the following day.