Reasons for KOSPI Circuit Breaker: How Leverage ETF Short Gamma Accelerated the Stock Market Crash
As KOSPI plunged 5.81% triggering the fifth circuit breaker of the year, massive foreign sell-offs and the mechanical selling (short gamma) of leverage ETFs were identified as the main culprits accelerating the crash.
On the 26th, the KOSPI index plummeted by 5.81%, closing at 8,411 and triggering the fifth circuit breaker (temporary trading halt) of the year. A massive net selling of 4.6 trillion won by foreign investors, combined with mechanical selling volume, known as 'short gamma', from single-stock 2x leverage ETFs, are pinpointed as the core factors that drastically amplified the market crash.
The Vicious Cycle of Circuit Breakers and Short Gamma Risks
This market crash initiated in tandem with the weakness in global tech stocks. Growing anxieties over sluggish demand from Apple and fears of a peak-out in the semiconductor sector caused massive large-cap tech stocks like Samsung Electronics and SK Hynix to plunge together by 5 to 8%. As the index slid under intense foreign selling pressure, the real problem erupted in the derivatives market.
The mechanical rebalancing sell-offs from single-stock 2x leverage ETFs, which have recently gained popularity among retail investors, triggered a severe 'Short Gamma' phenomenon. When underlying assets fall, leverage ETFs are forced to mechanically sell more stocks to maintain their target exposure ratios. This created a vicious cycle where a drop in stock prices triggered further sell-offs, eventually fulfilling the conditions for a Phase 1 circuit breaker as KOSPI briefly dropped over 8%. Extreme fear and 'panic selling' completely dominated the market.
Frequently Asked Questions (FAQ)
Q. What are the conditions for triggering a KOSPI circuit breaker?
A. A Phase 1 circuit breaker is activated when the KOSPI index drops by 8% or more from the previous day's closing price and sustains that level for 1 minute. Upon activation, all stock trading in the market is entirely halted for 20 minutes. It can only be triggered once a day.
Q. Why does the short gamma phenomenon in leverage ETFs accelerate a market crash?
A. 2x leverage products are designed to track double the daily return. Therefore, when stock prices plummet significantly, these funds must mechanically sell off their holdings into the market to maintain their target weighting. When such massive sell orders pour into a declining market, it acts as a 'supply-demand black hole,' artificially magnifying the downward spiral.