Sandisk Shares Surge 26% as Microsoft Earnings Revive AI Memory Trade

Key Takeaways

• Sandisk shares closed 25.99% higher at $1,279.96 before extending their total gain from the previous close to nearly 34% in after-hours trading.
• Microsoft’s strong cloud results revived confidence in AI infrastructure demand, helping Micron gain 18.4% and AMD rise 13%.
• Sandisk’s August 5 earnings and August 13 Investor Day could provide important updates on NAND pricing, enterprise SSD demand and supply agreements.

Sandisk Shares Lead the Semiconductor Rebound

source:tradingview

Sandisk shares surged 25.99% on Thursday, July 30, closing at $1,279.96 and ranking among the strongest performers in the S&P 500.

The rally continued after the closing bell. Sandisk traded at approximately $1,359 by 5:45 p.m. EDT, representing an additional after-hours gain of 6.18% and placing the stock nearly 34% above Wednesday’s closing price of $1,015.89.

The advance marked a sharp reversal following a multi-day decline across AI, semiconductor and memory-related stocks. Despite Thursday’s rebound, Sandisk remained approximately 46% below its June record high, underlining the scale of the recent volatility.

The wider technology sector also recovered. The Nasdaq Composite rose 2.8%, while the S&P 500 advanced 1.7% after recording its worst daily decline in seven weeks during the previous session.

Microsoft Earnings Restore Confidence in AI Spending

Microsoft’s fiscal fourth-quarter results provided the main catalyst for the technology rebound.

The company reported quarterly revenue of $90 billion, up 18% year over year. Microsoft Cloud revenue increased 27% to $59.3 billion, while Azure and other cloud-services revenue climbed 43%, according to the company’s official earnings release.

The results offered evidence that substantial investments in artificial intelligence and data-centre infrastructure were contributing to cloud growth and profitability. Microsoft shares consequently jumped 15.5%, recording their strongest session in nearly 18 years.

That performance helped restore confidence in companies supplying the processors, memory products and storage systems required for AI infrastructure. Micron Technology gained 18.4%, while Advanced Micro Devices rose 13%. The Philadelphia Semiconductor Index climbed by approximately 8%.

For Sandisk, the market response reflected renewed expectations that expanding AI workloads could support demand for enterprise solid-state drives and other products based on NAND flash memory.

Hedge Fund Transaction May Have Reduced Selling Pressure

The rebound also followed reports that Citadel had acquired a substantial part of the publicly traded stock portfolio held by Situational Awareness, the AI-focused investment fund founded by former OpenAI researcher Leopold Aschenbrenner.

The fund reportedly suffered significant losses after leveraged positions in AI-related companies declined and triggered margin calls. Its public-equity holdings were reported to include Sandisk and other AI infrastructure stocks.

The transaction was interpreted by some market participants as reducing the risk of further forced selling.

However, the removal of a potential technical seller does not change Sandisk’s underlying operating performance. The sustainability of the share-price recovery will still depend on NAND demand, pricing, margins and management’s outlook.

CXMT IPO Adds to Memory-Sector Uncertainty

Sandisk’s earlier decline occurred alongside concerns surrounding the stock-market debut of Chinese memory-chip producer ChangXin Memory Technologies, or CXMT.

CXMT shares rose 466% during their first session in Shanghai following an $8.6 billion IPO. The listing highlighted China’s growing ambitions in semiconductor manufacturing and contributed to selling across global memory stocks.

The competitive connection with Sandisk is not direct, however. CXMT primarily produces DRAM, which provides temporary working memory for processors, while Sandisk specialises in NAND flash, which provides persistent data storage.

Nevertheless, CXMT’s listing raised broader concerns about future Chinese semiconductor capacity, potential supply growth and competitive pressure across the memory industry. It also arrived as investors were already questioning whether valuations attached to AI hardware companies had risen faster than their near-term earnings potential.

Sandisk’s sharp decline and subsequent rebound may therefore reflect several overlapping factors, including sector contagion, leveraged selling, profit-taking and uncertainty over the durability of AI infrastructure spending.

Sandisk Earnings and Investor Day Move Into Focus

Investors will next turn to Sandisk’s fiscal fourth-quarter and full-year results, scheduled for August 5 after the US market closes.

The company will hold its earnings call at 1:30 p.m. Pacific Time. Sandisk has also scheduled an Investor Day for August 13, when senior management is expected to discuss the state of the business and its longer-term outlook, according to the company’s official announcement.

Key areas investors may monitor include:

• NAND flash pricing and supply conditions
• Enterprise SSD demand from cloud and AI customers
• Gross-margin sustainability
• Production and capacity plans
• Existing or potential long-term customer supply agreements
• Management’s fiscal 2027 revenue and earnings outlook

The results could help determine whether Sandisk’s recent decline represented an overreaction to market-wide selling or a more durable reassessment of AI-related memory demand. Thursday’s rebound improved short-term sentiment, but the stock’s wide price swings suggest that uncertainty remains elevated.