On the day when the US stock market falls sharply, will there be an epic collapse in the South Korean stock market? The answer is hidden in Samsung's financial report. On October 8th, Samsung Electronics announced its third quarter operating profit forecast of KRW 107.4 trillion, setting a new quarterly high for global technology companies. On the same day, KOSPI closed down 2.62%, Compared to the historical high of 9114 points, the retracement is about 27.3%, Despite record profits, the index of the South Korean stock market crashed first. Why? Because what determines the short-term trend of KOSPI is not how much money Samsung earns, but who is buying it. Samsung Electronics and SK Hynix together account for over half of KOSPI's weight. The rise and fall of two storage companies is the rise and fall of the South Korean stock market. But the buying spree is disappearing. Foreign investment is running. This year, there has been a net withdrawal of approximately $131 billion from the South Korean stock market, the largest outflow from major Asian markets. In September alone, Samsung and SK Hynix accounted for 76.6% of the net foreign sales. Samsung's foreign ownership ratio has dropped to 46.38%, while SK Hynix's has dropped to 49.59%, approaching its 2008 low. Retail investors are running. In the third quarter, retail investors sold a net of 5.59 trillion Korean won and bought a net of 7.632 billion US dollars in US stocks during the same period. Korean retail investors are voting with their feet. The only stable buyer is repurchase. Samsung launched a buyback of approximately 15 trillion Korean won in August, which was essentially completed in early October. SK Hynix is repurchasing approximately KRW 40 trillion, with a progress rate of about 80%. Goldman Sachs warns: ammunition will run out in mid October. Once the repurchase stops, there will be no net buyers for Korean stocks. What will happen if the US stock market crashes? The transmission path is very clear: US AI stocks fall → Storage chip demand expectations collapse → Samsung/SK Hynix sold off → KOSPI collapse. And Korean stocks will fall even harder than US stocks because: It does not have a 'non AI sector' to buffer it; It has been abandoned by leveraged funds and has extremely low liquidity; Its only buyer has run out of ammunition and supplies. The Korean stock market is not a matter of whether it will collapse or not, When did it collapse, It's a matter of who will take over the stock when it collapses. Will the South Korean government be the last to take over?