Margin calls, tighter leverage rules, and South Korea's first rate hike in over three years have triggered a sharp selloff in SK Hynix. Yet record ETF inflows suggest global investors are still chasing AI memory exposure—just through different vehicles.

SK Hynix Faces Its Biggest Test Since Its Nasdaq Debut

After becoming one of the world's hottest AI winners, SK hynix Inc. Sponsored ADR(SKHY.US) is suddenly facing its most severe correction.

The company's Korea-listed shares tumbled around 14% in a single session, while its U.S.-listed ADRs fell nearly 14%, erasing part of a rally that had driven the stock almost 600% higher over the past 12 months in the Korean market.

The selloff extends beyond company fundamentals. Instead, it reflects the unwinding of an increasingly leveraged AI trade built on three assumptions:

• AI memory demand would continue accelerating.
• A weak Korean won would keep supporting exports.
• Retail investors would keep buying every dip.

The first two assumptions may still hold. The third is beginning to break.

Margin Calls Are Turning a Correction Into Forced Selling

According to Goldman Sachs Managing Director Ioannis Blekos, more than 1.2 million Korean retail margin accounts had received margin calls as of July 13.

Roughly 320,000–360,000 accounts have already been forcibly liquidated by brokers.

For perspective, that means roughly one out of every 30 working-age Koreans has received a margin call—a remarkable indication of how deeply leveraged retail participation became during the AI rally.

Brokerage margin balances have reportedly fallen by about 30 trillion won, reaching their lowest level since February.

The importance of these figures isn't simply their size.

When forced liquidations begin, valuation often becomes irrelevant. Brokers are not deciding whether SK Hynix remains a long-term AI winner—they are selling whatever can be liquidated to satisfy collateral requirements.

That dynamic can accelerate declines regardless of company fundamentals.

Regulators Slam on the Brakes

Recognizing the risks, South Korea's Financial Services Commission introduced a series of measures aimed at cooling speculation.

The regulator announced it will:

• Suspend new listings of single-stock leveraged ETFs
• Ban marketing of those products
• Triple the minimum cash deposit required for new investors to 30 million won (around $20,000) beginning August 5

Many of these leveraged ETFs—launched only a few months ago—were designed to deliver 2x daily returns or more on individual companies such as SK hynix Inc. Sponsored ADR(SKHY.US) and SAMSUNG ELECTRONICS CO(SSNLF.US).

While these products amplified gains during the rally, they also magnify losses during downturns.

Because leveraged ETFs must rebalance their derivative exposure every trading day, volatility can feed on itself, increasing selling pressure during sharp declines.

The timing, however, may be late.

The market had already entered a deleveraging phase before regulators intervened.

Why the ADR Premium Matters

One of the more unusual developments has been the extraordinary pricing gap between SK Hynix's Nasdaq-listed ADRs and its Korea-listed shares.

The ADR premium recently reached 51%, before narrowing to roughly 27%.

Normally, arbitrage would quickly eliminate such discrepancies.

However, the ADR creation and cancellation process remains temporarily closed, preventing investors from efficiently converting between ADRs and local shares.

Without that arbitrage mechanism, the premium has remained unusually elevated.

That pricing distortion has also changed how global investors are gaining exposure to SK Hynix.

ETFs Have Become the Preferred Alternative

Rather than paying a steep premium for ADRs, many investors are choosing Korean equity ETFs.

The clearest beneficiary has been the iShares MSCI South Korea ETF(EWY.US).

Key figures illustrate the scale of demand:

For many institutional investors, EWY has effectively become a proxy for owning SK Hynix while avoiding the unusually expensive ADR market.

ETF strategists describe funds like EWY as efficient "proxy trades" that provide exposure to Korean technology without the operational complexity of buying local shares.

Is the AI Memory Story Over?

What appears to be changing is where capital is flowing, rather than whether investors still believe in AI infrastructure.

Several global investment managers argue that money leaving Korea is increasingly rotating into Chinese and Taiwanese technology stocks, like Taiwan Semiconductor Manufacturing Co., Ltd. Sponsored ADR(TSM.US), where valuations remain relatively lower and leverage appears less excessive.

The broader AI investment thesis—including demand for high-bandwidth memory (HBM), AI servers and cloud infrastructure—remains largely intact.

The more immediate challenge is market positioning.

When leverage dominates a rally, corrections often become more violent than fundamentals alone would justify.

Stocks and ETFs to Watch

Investors following the next phase of the AI memory trade may want to monitor:

Key Takeaways

The recent decline in SK Hynix is less about deteriorating AI fundamentals than about the unwinding of one of the world's most crowded leveraged trades.

Margin calls, tighter regulation and higher interest rates have exposed how dependent the rally had become on retail leverage.

Yet the record inflows into Korean ETFs—and continued investor interest in AI infrastructure—suggest capital is not abandoning the semiconductor theme altogether.

Instead, investors appear to be becoming more selective, looking for lower-cost and lower-risk ways to participate in the next stage of the AI memory cycle.