KOSPI Triggered Its Second Circuit Breaker in Three Days

South Korea's AI chip trade just broke its own market — not because memory demand collapsed, but because two stocks, borrowed money, and 2x leveraged ETFs turned a routine selloff into a circuit-breaker crisis.

What happened:

• On June 27, the KOSPI closed down 519 points (5.81%) at 8,411 after falling more than 8% intraday — triggering a 20-minute marketwide circuit breaker, The Korea Herald reported.
• It was the second circuit breaker in three trading days — and the fifth this year.
• Market cap evaporated by 425 trillion won (~$275 billion) in a single session, per Seoul Economic Daily.
• Three days earlier, the index suffered its largest one-day drop on record — down 910 points (9.99%) — erasing 742 trillion won.

Why Korea, not Taiwan or Japan:

• Samsung Electronics and SK Hynix alone account for 58% of KOSPI market cap as of June 27.
• Taiwan and Japan also fell on the global chip selloff. Their losses were a fraction of Seoul's.
• Analysts told The Korea Herald the plunge "could not be explained by the global semiconductor sell-off alone."

The leverage machine:

• On May 27, regulators approved single-stock 2x leveraged ETFs tied to Samsung and SK Hynix — products that seek double the daily return of one underlying share.
• By June 27, those products held 14 trillion won in assets, with 92% retail ownership, per Financial Supervisory Service data cited by The Korea Herald.
• When chip prices fall, the ETFs must cut exposure to maintain target leverage — selling that pushes prices lower, which forces more selling.
• On June 24, the average 2x SK Hynix ETF fell 25.6% while the underlying stock dropped 12.5%, The Chosun Ilbo reported.

Regulators are panicking:

• Financial Supervisory Service Gov. Lee Chan-jin said he "personally regret[s] the timing of the approval" of the leveraged products.
• "We are seeing a situation where the tail is wagging the dog," Lee told reporters Monday. "There is a risk that investors gain little while securities firms and liquidity providers earn most of the profits."
• Margin loan balances hit a record 38.5 trillion won by June 22 — double the level a year earlier, per the Korea Financial Investment Association.

The global AI triggers:

• Friday's selloff followed a U.S. tech rout driven by Apple price hikes, OpenAI IPO delay reports, and fading AI monetization hopes.
• Eugene Investment analyst Heo Jae-hwan cited "weakness in US technology shares" and the New York Times report that OpenAI may delay its IPO until 2027.
• Kiwoom Securities analyst Han Ji-young said memory-demand fears were "excessive" — the real driver was concentration and market flows, not fundamentals.

Retail bought the falling knife:

• Individual investors net-bought 8.17 trillion won on June 27 — the second-largest dip-buying day on record, per Seoul Economic Daily.
• Foreign investors net-sold 4.65 trillion won the same session.
• The VKospi fear gauge hit 97.78 on June 24 — its highest level since the 2008 financial crisis.

Convina's view:

Korea is the canary for the global AI trade — not because its chipmakers are weak, but because its market structure is absurd. When 58% of a G20 benchmark sits in two memory suppliers and regulators green-light 2x single-stock ETFs for retail, every OpenAI IPO rumor and Apple price hike becomes a national emergency. Wall Street is debating whether AI capex earns a return. Seoul is living the answer in real time: the infrastructure bill is real, the leverage is real, and the circuit breakers are the new normal.