In a historic shift for the South Korean stock market, SK Hynix has overtaken Samsung Electronics to become the largest company on the KOSPI by market capitalization. This development marks the end of an era, as Samsung Electronics had held the top position for over 25 years, serving as the undisputed bellwether for the nation’s economy. The transition highlights a dramatic transformation in the global semiconductor landscape, driven primarily by the explosive demand for artificial intelligence (AI) chips.

According to the Korea Exchange on June 22, 2026, SK Hynix shares saw a significant rally, climbing 3.58% to 2,863,000 won as of 1:38 PM. Meanwhile, Samsung Electronics’ stock experienced a decline of 1.41%, trading at approximately 349,000 won. Consequently, SK Hynix’s market capitalization reached 2,040.47 trillion won, narrowly surpassing Samsung Electronics’ 2,040.35 trillion won. While the difference in market value for common shares is relatively small—approximately 115 billion won—the psychological and industrial impact of this overtake is profound. It is important to note, however, that when including preferred shares, Samsung Electronics still maintains a total market valuation significantly higher than that of SK Hynix.

The dominance of Samsung Electronics had been unchallenged since the company first claimed the top spot on July 29, 1999. After some fluctuations, it solidified its leadership position on November 21, 2000, and maintained its status as the KOSPI’s most valuable firm for roughly 25 years and 7 months. During this quarter-century, Samsung grew from a domestic electronics manufacturer into a global technology powerhouse.

SK Hynix’s rise to the top has been a long-term strategic evolution. The company reached the number two spot in the KOSPI rankings on November 7, 2014, but at that time, its market capitalization was less than one-seventh that of Samsung Electronics. Over the past decade, however, the gap between the two tech giants has steadily narrowed, evolving into a fierce "duopoly" that defines the Korean semiconductor industry.

The catalyst for this recent breakthrough has been the AI revolution. As major global tech firms ramp up investments in AI servers, the demand for High Bandwidth Memory (HBM)—a field where SK Hynix holds a competitive edge—has surged. This strategic focus allowed SK Hynix to capitalize on the market shift more effectively than its rivals. Since the latter half of last year, the stock price gap between the two companies began to shrink rapidly. As recently as June 19, SK Hynix’s market cap had reached 95.17% of Samsung’s, setting the stage for the historic flip observed today.

Industry analysts interpret this change as a testament to the specific technological demands of the current era. While Samsung Electronics maintains a diversified portfolio ranging from smartphones to home appliances and foundry services, SK Hynix has successfully concentrated its resources on the high-growth memory sector critical for AI.

This change in the KOSPI hierarchy does not necessarily signal a decline for Samsung, but it undeniably signals a new chapter for the Korean financial market. As the industry moves further into the AI era, the competition between these two semiconductor giants is expected to intensify, continuing to drive innovation and shaping the future of global technology. For investors and market observers, the shift from a single-leader structure to a highly competitive environment between these two heavyweights marks a new milestone in Korea’s economic history.