Samsung Electronics (005930) · SK Hynix (000660)
AI Memory Leadership: The HBM4 Battleground Between Samsung and SK Hynix
The South Korean stock market opened with a sharp focus on the semiconductor sector this morning, as the race for High Bandwidth Memory (HBM) supremacy enters a critical new phase. As of March 23, 2026, the AI Memory Leadership transition is becoming the primary driver for KOSPI movements, with both Samsung Electronics and SK Hynix positioning themselves for NVIDIA’s next-generation “Rubin” architecture.
According to the latest data from Naver Finance and the Korea Exchange (KRX), the KOSPI index stands at 5,781.20, up 0.31%, while the KOSDAQ has surged by 1.58% to 1,161.52. This divergence highlights a rotation into high-growth tech and secondary battery stocks, but the underlying narrative remains tethered to the AI Memory Leadership held by the giants of Suwon and Icheon.
The HBM4 Supply Chain Realignment
Korea Exchange (KRX) filings and company earnings guidance confirm that Samsung Electronics (005930) and SK Hynix have both transitioned from prototype testing to delivering “paid final samples” of HBM4 to NVIDIA. This milestone marks the end of the free evaluation period and the beginning of a commercially driven supply phase. For Samsung, this is a pivotal moment to regain market share after the protracted certification cycles seen with HBM3E during late 2024 and 2025.
SK Hynix (000660), the incumbent leader in HBM3E, is not resting on its laurels. The company has reportedly secured a unique competitive position by maintaining its leadership in current-generation supply while simultaneously establishing a robust mass-production system for HBM4. The market anticipates that HBM4 shipments will commence in earnest within the next few months, fueling a “memory supercycle” that could carry the KOSPI toward the 6,000-point psychological barrier.
Market Sentiments and Sector Performance
The AI Memory Leadership theme has also influenced the broader technology ecosystem. While the internet and platform giants like NAVER (035420) and Kakao (035720) have seen relatively stable trading at 221,500 KRW and 50,000 KRW respectively, the capital expenditure (CAPEX) flows are overwhelmingly favoring hardware. Foreign institutional investors remain net buyers in the semiconductor space, drawn by the 20% price hike for 2026 HBM3E orders, which suggests that demand continues to outstrip supply despite capacity expansions.
Investment Strategy for Kstocks.net
Investors tracking the Korean market on kstocks.net should monitor the upcoming first-quarter earnings guidance from Samsung Electronics, expected in late April. The key metric will not just be the bottom-line profit, but the percentage of revenue derived from HBM4 and advanced packaging services. As the AI memory landscape shifts from “performance at any cost” to “efficiency and integration,” the battle for AI Memory Leadership will determine the KOSPI’s trajectory for the remainder of the year.
Data Source: Naver Finance, KRX, Industry Reports.
Disclaimer: The information provided in this article is for informational purposes only and does not constitute investment advice. Investing in the stock market involves risks, including the loss of principal. Always consult with a qualified financial advisor before making any investment decisions.
About the Author
Johnny Lee
Seoul-based full-time professional and individual investor with 5 years of active experience in the Korean stock market. My approach combines value investing with medium-term swing trading across a diversified portfolio. In 2025, my personal account delivered a 72.9% return, significantly outperforming the KOSPI benchmark. I started KStocks to bring the Korean investor perspective directly to a global English-speaking audience.
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