SK Hynix Stock Surges 20.6% as Memory Rally Lifts Micron and SanDisk

Key Takeaways

• SK Hynix stock gained 20.6% last week, substantially outperforming the broader US equity market.
• SK Hynix retained a 22% share of global NAND shipments as demand from AI servers supported enterprise storage growth.
• Micron moved back towards $1,000, while SanDisk’s ambitious outlook added momentum to the wider memory chip rally.

SK Hynix Stock Gains More Than 20% in One Week

SK Hynix’s 20.6% weekly increase comfortably exceeded the S&P 500’s 1.2% gain and the Nasdaq Composite’s 1.7% advance over the same period. The move represented a sharp recovery from the volatility that followed the company’s US market debut in July.

The stock ended the week at $166.33, placing it above its $149 ADR offering price but still below its 52-week high of $194.80. Its wide $124.80–$194.80 trading range illustrates how quickly sentiment has shifted around AI memory stocks since the listing.

Wednesday produced the largest single-session move, with SK Hynix shares jumping 9%. The rally continued through the remainder of the week as investors responded to both company-specific developments and improving sentiment across South Korea’s semiconductor industry.

Temasek Reports Boost Korean Semiconductor Shares

One catalyst was a report that Singapore’s Temasek could make additional investments in SK Hynix and Samsung Electronics. The prospect of support from a major sovereign wealth fund strengthened market confidence in South Korea’s two largest semiconductor companies.

However, no new investment commitment was formally confirmed. Temasek indicated that it had previously invested in both companies and that its investment decisions were independent of advice from the South Korean government.

The report should therefore be viewed primarily as a sentiment catalyst rather than a confirmed change to SK Hynix’s earnings outlook. Even so, it arrived when Korean semiconductor shares were recovering from a steep July correction, allowing the story to have a larger effect on short-term market momentum.

NAND Market Data Supports the Fundamental Outlook

Fresh NAND shipment data gave the rally a stronger fundamental foundation. SK Hynix retained second place in the global market during the second quarter of 2026, with a 22% shipment share. Samsung remained the largest supplier with 25%.

SK Hynix benefited from a 40% quarter-on-quarter increase in bit shipments from Solidigm, its enterprise storage subsidiary. At the same time, enterprise solid-state drives accounted for 48% of global NAND shipments, almost double their 26% share one year earlier.

This shift reflects the growing storage requirements of AI inference. Large AI systems need rapid access to model data, datasets and key-value caches, increasing demand for high-capacity enterprise SSDs alongside traditional high-bandwidth memory.

Server SSDs could absorb more than half of all NAND bits by the end of 2026, potentially keeping supply tight and supporting average selling prices. The latest NAND market data therefore strengthened the argument that AI demand is benefiting a wider range of memory products rather than HBM alone.

SK Hynix’s recent results reinforce that view. The company reported second-quarter revenue of 79.32 trillion won and operating profit of 60.54 trillion won, supported by high-value DRAM, HBM and NAND products. It also began mass shipments of HBM4 and secured long-term agreements with around 10 major customers. SK Hynix’s Q2 results showed how tight supply and AI-related demand have translated into higher revenue and profitability.

Micron Stock Moves Back Towards $1,000

Micron joined the rally, climbing for a fourth consecutive session on Friday. The stock reached an intraday high of $984 before closing at $971.66, up 2.3%.

The $984 level was Friday’s session high rather than a new 52-week high. Micron’s actual 52-week peak remains $1,255, meaning the stock is still trading more than 20% below its June record despite its recent recovery. Micron’s latest market data confirms the distinction.

The company’s underlying results remain a central part of the bullish memory narrative. Fiscal third-quarter revenue reached $41.46 billion, compared with $23.86 billion in the previous quarter and $9.30 billion one year earlier.

Micron has described AI-driven memory and storage growth as outpacing industry supply. It is investing heavily in new technology and production while using multi-year customer agreements to improve revenue visibility. Micron’s fiscal Q3 results highlighted the sharp improvement in demand, pricing and margins.

SanDisk Outlook Adds Momentum but Yen Risk Remains

SanDisk provided another catalyst through its 2026 investor day. The company expects revenue to grow at a mid-to-high-teens annual rate between fiscal 2028 and fiscal 2030. It also presented targets of approximately 80% non-GAAP gross margins and 75% operating margins.

The outlook is based partly on growing demand for High Bandwidth Flash, which SanDisk is positioning as a storage solution for AI inference. The company also expects to return all excess cash to shareholders after funding business investment. SanDisk’s long-term financial model helped its shares gain around 35% during the week.

Foreign-exchange movements nevertheless remain an important risk. SanDisk sources much of its flash memory through Japanese manufacturing ventures with Kioxia. Its wafer purchases and investments in these ventures are denominated in Japanese yen.

A stronger yen against the US dollar would therefore increase SanDisk’s wafer-purchasing and future capital-funding costs, potentially placing pressure on profitability. This exposure is identified in SanDisk’s regulatory filings.