[COVER STORY] Black Thursday: KOSPI plunges 7% amid AI spending fears

On Thursday, the Korean stock market, as measured by the KOSPI index, experienced a significant downturn, plummeting by 7.57 percent. This resulted in an estimated loss of 400 trillion won, or approximately $297.7 billion, in market capitalization. The KOSPI index closed at 5,554.22, reflecting a steep decline of 7.57 percent.

The market's bearish sentiment was triggered by concerns surrounding the sustainability of artificial intelligence (AI) spending and the broader outlook for the semiconductor sector. A sell-side sidecar was activated at 9:07 a.m., marking the 27th occurrence of such a mechanism this year. This was followed by a Level 1 circuit breaker at 12:38 p.m. A sell-side sidecar is triggered when the most actively traded KOSPI 200 future experiences a decline of at least 5 percent from the previous session, while a Level 1 circuit breaker is initiated when the benchmark index declines by at least 8 percent from the prior close within a one-minute timeframe.

Foreign investors played a substantial role in exacerbating the market's decline, offloading 3.6 trillion won worth of shares. This marked their eighth consecutive trading session of net selling. Institutional and retail investors, however, acted as market stabilizers by purchasing 1.69 trillion won and 1.29 trillion won worth of shares, respectively. Their actions allowed them to acquire shares at discounted prices, potentially mitigating the impact of the broader market downturn.

The market's heavy selling was particularly detrimental to market leaders. Samsung Electronics, a prominent player in the semiconductor sector, saw its stock price plummet by 9.48 percent. As of the close of trading, the company's shares were down significantly, reflecting the broader market's concerns over AI spending trends and the semiconductor industry's future prospects.