The world's memory chip sector is undergoing a transformation with few modern parallels as relentless demand from AI development triggers a historic repricing of the semiconductor industry.
South Korea's SK Hynix shares surged as much as 13% in Seoul trading on Wednesday, reaching a new all-time high and pushing its market capitalisation above $1 trillion (€860bn) for the first time.
SK Hynix is now only the second South Korean company and the third Asian company overall to enter the trillion-dollar club, following rival Samsung Electronics, which crossed the threshold earlier this month, and Taiwan's TSMC before it.
The firm's shares have now risen approximately 250% since the start of the year, while the stock's gain since April 2025 has exceeded 1,200%.
The milestone arrived a day after Micron Technology soared 19% on Wall Street, its biggest single-session gain since 2011, propelling the American chipmaker past the same valuation mark simultaneously.
The company's shares have jumped roughly 190% since the beginning of 2026, while the stock's gain since April 2025 has crossed 1,300%.
Both firms are dominant suppliers of high-bandwidth memory (HBM), the specialised chips at the core of AI accelerators and data centre servers. SK Hynix, a key supplier to Nvidia, has already sold out its entire 2026 HBM production capacity.
May 2026 has, within the space of a few weeks, become a month defined by trillion-dollar breakthroughs for the global memory industry. The semiconductor rally has been a key driver behind one of the most remarkable stock market surges in recent years.
South Korea's KOSPI has also been a major beneficiary of the rally. The index rose as much as 2.9% on Wednesday to a new all-time high of 8,457 points.
The KOSPI is also up over 100% since the start of the year, after falling more than 20% during March when the Iran war broke out.
From its lows in December 2024, the index has more than doubled, one of the fastest re-ratings of any major global benchmark in recent memory.
SK Hynix eyes US listing, but risks remain
The next chapter for SK Hynix may be written in the US markets.
The company has filed with the US Securities and Exchange Commission to list American Depositary Receipts (ADRs) in the United States, with reports suggesting the offering could raise billions of dollars in the second half of 2026.
Proceeds are earmarked for its Yongin HBM production hub in South Korea and its packaging facility in Indiana.
ADRs are negotiable certificates issued by US depositary banks that represent ownership shares in foreign companies. They allow American investors to buy and trade foreign stocks on US stock exchanges without the complexities of cross-border transactions or currency conversions.
SK Hynix is using the instrument to attract American capital for large-scale infrastructure investment projects.
