Why did South Korea’s central bank rate hike first crash storage chip stocks?

What the market should pay the most attention to today is not only South Korea’s central bank rate hike, but the fact that this hike rapidly spread through exchange rates, leveraged funds, and semiconductor valuations—eventually turning into a concentrated sell-off in tech stocks.

On July 16, the Bank of Korea raised the benchmark interest rate by 25 basis points to 2.75%, the first rate hike since January 2023. The reasons behind it are not complicated: energy prices have risen, the Korean won has remained under pressure, inflation has returned to above 3%, and in addition, household debt and real estate prices are heating up—leaving the Bank of Korea with little room to keep easing.

But the rate hike was only the trigger.

The day before, driven by a surge in US-listed storage-chip stocks, South Korea’s KOSPI index rose more than 7% at one point; SK hynix gained over 11%. Just one day later, market sentiment flipped completely: KOSPI fell more than 6%, Samsung Electronics dropped about 6.6%, and SK hynix fell about 9%. This roller-coaster price action shows that in today’s South Korean tech stocks, it’s not just long-term capital that has piled in—there are also large amounts of short-term money, margin positions, and leveraged ETFs.

Especially in the memory sector, the key logic for trading over the past period has been that AI demand drives up the prices of HBM, DRAM, and NAND. But when share prices front-run the earnings outlook and, once the risk-free rate rises, the valuation discount rate also increases, high-valuation assets that originally relied on forward growth to justify their premiums often become the first targets for selling.

SK hynix’s situation is even more special. After its US ADR listing, it drew strong interest from funds, and the ADR traded at a significant premium versus the local Korean shares. As the end-of-month conversion mechanism gradually opens up, arbitrage capital may push the prices in the two markets back closer together. This means that even if the company’s fundamentals do not suddenly deteriorate, the valuation gap could still be closed through ADR declines, local share increases, or adjustments on both sides.

So, this sell-off cannot be simply understood as “the end of the memory cycle.”

More accurately, the rate hike broke the market’s prior liquidity expectations, leveraged ETFs amplified volatility, ADR premiums increased valuation disputes, and ultimately cooled down crowded AI memory trades. South Korea’s regulators have also started studying new measures targeting leveraged ETFs for individual stocks, indicating that regulators are aware of how leveraged products magnify market volatility.

Next, whether memory stocks can stabilize cannot be judged just by day-to-day price moves. Instead, watch three signals: whether the Bank of Korea continues to release rate-hike signals, whether the Korean won can hold steady, and whether the rise in DRAM and HBM prices can truly translate into corporate profits.

Fundamentals haven’t disappeared, but when valuation, leverage, and monetary policy all change at the same time, even the best track needs to be repriced. #韩国KOSPI暴跌5%触发熔断 #盘前合约上线长鑫存储 #夏日创作营 @Gate 广场