SK Hynix Again Hits Limit Down in NXT Premarket, Reviving Opening-Price Debate

NXT to Introduce Static Volatility Interruption on Sept. 14

SK Hynix reignited controversy over opening-price distortions on Aug. 6 after the stock opened at the daily limit down in the premarket session of alternative trading venue Nextrade, or NXT.

According to the financial investment industry, 11 shares of SK Hynix traded at 1.168 million won immediately after the premarket opened between 8 a.m. and 8:50 a.m. That was 29.97% below the previous session's close of 1.668 million won. A Volatility Interruption, or VI, was triggered immediately, shifting trading to a two-minute call auction. When trading resumed, the decline quickly narrowed to about 3% to 4%.

Unlike the regular session, NXT sets opening prices through continuous matching rather than a call auction. The structure can allow price distortions from small-lot trades alone. A similar case occurred on July 28, when a single share of SK Hynix was executed at the daily lower limit of 1.272 million won immediately after the premarket opened.

The effect on the cash market was limited because only one share was involved. But that trade was reflected in the reference price for an SK Hynix perpetual futures product in the crypto derivatives market, triggering about 83 billion won in forced liquidations.

NXT plans to introduce a static VI on Sept. 14 to reduce abnormal trades. If an order is submitted at a price more than 10% away from the previous day's close or the reference price, it will not be executed immediately. Instead, trading will shift to a two-minute call auction, and orders will be matched at an equilibrium price.

Noh Jeong-dong, Hankyung.com reporter, dong2@hankyung.com