SK Hynix on Monday overtook Samsung Electronics to become South Korea’s most valuable listed company, marking a dramatic reversal of fortunes for a chip maker that two decades ago nearly collapsed under debt.

The company, now the dominant supplier of high-bandwidth memory (HBM) chips used in AI systems for customers such as Nvidia and Google, has emerged as one of the biggest beneficiaries of the global AI boom, helping propel its shares up more than 340% this year and lifting its market value above both Samsung Electronics and Micron.

Shares of SK Hynix, now the world’s most valuable memory-chip maker, traded up 5.7% to bring the company’s market capitalisation to the equivalent of US$1.35-trillion (R22.2-trillion).

The stock hit the milestone as AI reshapes the global semiconductor industry, elevating specialised memory chips from commonly traded commodities into critical components of the infrastructure powering applications such as ChatGPT and advanced AI models.

SK Hynix focuses primarily on memory chips, versus Samsung Electronics whose business also involves manufacturing logic chips as well as electronics. Samsung Electronics had held the top spot since 2000.

“The emergence of customised AI memory fundamentally changed the industry’s economics and allowed SK Hynix to establish itself as the market leader,” said Kim Sunwoo, a senior analyst at Meritz Securities.

For SK Hynix, the achievement marks the culmination of one of the biggest turnarounds in South Korea’s corporate history.

Crippled

In 2002, then-Hynix Semiconductor was on the verge of being sold to Micron, having been crippled by debt accumulated during an aggressive expansion drive. The deal eventually fell through, leaving the company under creditor control for nearly a decade.

Its shares plunged as low as ₩135 in 2003, leaving it viewed as a penny stock, or “Dongjeon-ju” in Korean, among investors.

Read: Memory makers SK Hynix and Micron join the $1-trillion club

Its fortunes in the years since tracked the global memory industry’s traditional boom-and-bust cycle. In 2023, a severe downturn battered memory prices, pushing SK Hynix to report an annual operating loss of ₩7.73-trillion.

It started recovering a year later as the AI boom gained momentum and the likes of Microsoft, Google and Meta invested heavily, pushing it to report an annual operating profit of ₩23.5-trillion won in 2024, a record at the time. — Heekyong Yang, (c) 2026 Reuters