South Korea’s benchmark KOSPI index extended its historic selloff, plunging as much as 9.8% on Wednesday and triggering a market-wide circuit breaker for a second consecutive session. The sharp decline followed SK Hynix Inc.’s failure to meet profit expectations despite record revenue, exacerbating fears over competition from China’s memory chip sector. The index briefly fell below the 6,000 mark, its lowest level since early April, putting U.S.-listed South Korea exchange-traded funds (ETFs) under intense pressure as their fortunes remain tightly linked to the artificial intelligence trade.

The rout was driven by SK Hynix’s second-quarter results, which showed record revenue of 79.32 trillion KRW ($54.53 billion), up 257% year-over-year. However, operating profit of 60.54 trillion KRW ($41.62 billion) missed the LSEG SmartEstimate forecast of 64 trillion KRW ($43.99 billion). Although operating margins hit an all-time high of 76%, investors aggressively dumped the stock, with shares falling 9.61%. Samsung Electronics also slid 5.23%. Together, these two heavyweight chipmakers account for more than half of the KOSPI’s total weighting, making the index a direct proxy for global AI hardware sentiment.

ETF Volatility and Concentration Risk

The synchronized selloff severely impacted memory-focused and broad-market ETFs. The iShares MSCI South Korea ETF (EWY), which manages more than $23 billion in assets, dipped 6.1% on Tuesday and was down 3.1% Wednesday pre-market. Despite tracking 78 stocks, EWY is heavily concentrated in Samsung Electronics and SK Hynix, meaning the fortunes of two semiconductor companies largely determine the fund’s performance. The Franklin FTSE South Korea ETF (FLKR), a lower-cost alternative charging 0.09%, fell 5.2% on Tuesday and was down almost 4% in pre-market trading Wednesday.

Leveraged products faced steeper losses. The Direxion Daily MSCI South Korea Bull 3X Shares (KORU), which seeks three times the daily performance of South Korean equities, saw an 18% erosion of its price on Tuesday before sliding almost 20% overnight. KORU is now headed for its worst monthly decline on record, down nearly 64% in July, although it remains up about 35% for 2026. This extreme volatility underscores the risks for tactical traders using leveraged instruments during periods of high market stress.

Retail Investor Impact and Market Structure

The pain has been especially acute for retail investors, who helped fuel South Korea’s AI rally through margin loans and leveraged ETFs. Finance Minister Koo Yun-cheol apologized this week after recent rule changes sparked a surge in speculative trading. Since the launch of single-stock leveraged ETFs in late May, Korean retail investors have bought about 14 trillion won of the products, compared with roughly 2 trillion won by foreign investors, according to KB Financial Group. On Wednesday alone, retail investors sold about 1.7 trillion won ($1.2 billion) of Korean equities as forced liquidations accelerated.

"There have been a lot of forced liquidations today," said Jung In Yun, CEO of Fibonacci Asset Management Global. "We need to wait out until selling from retail investors ease." The Kosdaq Index also fell more than 8%, triggering its own 20-minute trading halt. Remarkably, nine of the KOSPI’s 15 circuit breakers since 2000 have occurred this year, highlighting the structural fragility introduced by high leverage and concentrated ownership.

What the Numbers Show

The divergence between recent AI-driven valuations and current price action highlights the fragility of momentum-led rallies. Analysts warn that the market has been oblivious to Chinese competition until now, leading to an overreaction driven by retail traders rather than fundamental shifts in near-term supply. Kim Seok-hwan, a Seoul-based market analyst at Mirae Asset Securities, noted that concerns lie less in ChangXin Memory Technologies’ current earnings and more in its potential for accelerated capacity expansion. With the Federal Open Market Committee meeting underway, investors face additional uncertainty; while consensus expected rates to remain unchanged, macroeconomic pressures suggest a potential surprise decision. The crash underscores a critical inflection point where geopolitical technological risks are re-pricing global semiconductor assets.

SK hynix Inc. (NASDAQ: SKHY) delivered a decisive rebuttal to Wall Street’s bearish thesis on artificial intelligence memory demand, announcing record-breaking second-quarter financial results on July 28, 2026. The South Korean semiconductor giant reported revenues of 79.3187 trillion won and an operating profit of 60.5426 trillion won, marking a historic peak in profitability that invalidates recent market concerns about a structural slowdown in AI infrastructure spending. With shares having plunged nearly 47% since mid-July highs amid fears of Chinese competition and fading demand, the earnings data confirms that high-bandwidth memory (HBM) contracts remain robust and pricing power is intact.

The financial performance represents a dramatic acceleration from the prior period. Revenue surged 257% year-over-year from 22.232 trillion won in Q225 and grew 51% quarter-over-quarter from 52.5763 trillion won in Q126. Operating profit expanded even more sharply, rising 557% year-over-year and 61% quarter-over-quarter. The company achieved an unprecedented operating margin of 76%, up 35 percentage points from the same quarter last year. Net income reached 93.9226 trillion won, a 1,242% increase year-over-year, driven by strong sales of high-value-added products including HBM, DRAM for AI servers, and eSSD. Cumulative revenue for the first half of FY26 surpassed 100 trillion won for the first time in the company’s history.

Financial Performance And Balance Sheet Strength

SK hynix’s balance sheet strengthened significantly alongside its operational gains. Cash and cash equivalents rose to 88 trillion won at the end of the second quarter, an increase of 33.6 trillion won from the previous quarter. Total debt decreased by 0.7 trillion won to 18.6 trillion won, expanding the net cash position to 69.4 trillion won. Management stated that this liquidity provides significant financial flexibility to support mid-to-long-term growth opportunities while adhering to capital expenditure discipline.

Product Strategy And Long-Term Contracts

The record results were underpinned by sustained demand for advanced memory technologies. SK hynix began mass shipments of HBM4 in the second quarter, noting that the product achieved customer-required operating speeds with industry-leading power efficiency and cost competitiveness. The company plans to ramp up HBM4 production in the second half of the year. Additionally, sample shipments of HBM4E were completed in the first half, utilizing optimal processes focused on technology maturity and mass-production stability.

To secure supply stability, SK hynix finalized Long-Term Agreements (LTAs) with around 10 key customers, including major strategic partners. These multi-year contracts address structural demand growth as AI evolves into agentic forms performing complex tasks. In NAND flash, the company is accelerating its transition to advanced nodes, with 321-layer products now representing the largest share of total production. SK hynix aims to expand this capacity to approximately 50% of domestic production by year-end.

What The Numbers Show

The divergence between SK hynix’s stock performance and its operational reality highlights a severe mispricing by investors. While the share price declined nearly 47% on fears of demand destruction, physical export data and these earnings results confirm exceptional strength. The 76% operating margin demonstrates that SK hynix retains significant pricing power despite competitive pressures from Chinese manufacturers like ChangXin Memory Technologies. The surge in net cash to 69.4 trillion won further insulates the company from cyclical volatility, allowing it to fund upcoming investments such as the Yongin Phase 1 cleanroom opening in early 2027 and the P&T7 advanced packaging facility without compromising financial health.