Samsung Electronics and SK Hynix are in focus on Monday after closing sharply higher on Friday, as a long-term margin forecast from US flash-memory maker SanDisk gave investors reason to reassess how long the AI-driven memory boom could last.
South Korean markets are closed Monday for the Liberation Day holiday.
On Friday, Samsung rose 2.43% to 274,500 won and SK Hynix climbed 3.26% to 1.645 million won, helping the KOSPI finish 2.41% higher at 6,977.34.
The catalyst was SanDisk’s investor day, where the company laid out a framework that challenged assumptions about memory cyclicality.
SanDisk expects mid- to high-teens revenue growth from fiscal 2028 through 2030, alongside non-GAAP gross margins of about 80% and operating margins near 75%.
SanDisk’s 80% target changes the memory debate
For Samsung and SK Hynix, the significance lies in what those targets imply for the industry.
Memory has historically followed a familiar pattern. Strong pricing boosts profits, encourages investment and eventually brings enough new supply to crush margins.
SanDisk is arguing that AI demand, tight capacity and longer-term customer agreements could keep industry profitability far above historical norms for years.
JPMorgan analyst Harlan Sur said SanDisk was “uniquely positioned to capture the ongoing structural inflection in NAND demand” driven by AI inference.
He also argued that longer customer agreements had improved the company’s margin profile while reducing the boom-and-bust volatility associated with memory.
Morgan Stanley analyst Joseph Moore offered another bullish read.
MarketWatch reported that Moore believes SanDisk could “stay at or above these margin levels for multiple years” while shortages persist, although he questioned whether operating margins around 75% could be sustained indefinitely.
Wall Street sees a shortage that could run for years
That message fits a shift in analyst expectations around the memory cycle.
Macquarie Capital analysts said the industry is facing the “worst memory crunch in history” and see no sign of supply constraints easing within the next three years.
The firm described AI inference-related memory demand as “off the charts” and expects Samsung and SK Hynix to lead the Korean market’s near-term recovery.
Inference matters because running AI models at scale requires vast amounts of memory and storage, not just computing power.
As AI usage expands, data centres need more HBM and DRAM, while NAND demand can rise as operators seek cheaper ways to store and retrieve the vast quantities of data generated by AI workloads.
Bernstein analyst Mark Newman told MarketWatch that SanDisk’s planned high-bandwidth flash could become a “huge new growth driver for NAND demand.”
He added that the technology could consume substantially more wafer capacity, potentially keeping supply conditions tighter for longer.
High margins still carry an old cyclical risk
The bullish case does not mean the memory cycle has disappeared.
Moore’s caution is important. SanDisk’s current profitability reflects an exceptional shortage, and an 80% gross-margin framework leaves little room for disappointment if supply expands faster than expected.
The same risk applies to Samsung and SK Hynix.
Both stand to benefit if AI infrastructure spending continues to absorb new capacity, but high prices also give manufacturers a powerful incentive to invest in additional production capacity.
