Why Sandisk Stock Skyrocketed 857% In the First Half of 2026

SanDisk (SNDK) surged 857.8% through end-June 2026 as AI-driven data center buildouts lifted NAND flash demand and pricing. In Q3 2026, gross profit margins jumped to 78% from 51% y/y, alongside revenue up 251% to $5.9B and earnings turning to $23.41/share from a $(0.30) loss. The company also secured five multi-year supply agreements totaling $11B in guarantees, supporting continued growth; analysts expect Q4 sales of $8.4B and EPS of $34.12 on Aug. 5.

Analysis

SNDK is benefiting from a classic memory upcycle, but the market is likely extrapolating peak margins as if they are structural. In NAND, pricing power usually arrives with a 2-4 quarter lag after hyperscaler demand spikes, then fades once OEMs and cloud buyers rebuild inventory and foundries redirect capex back into supply. That makes the near-term setup favorable, but the 6-18 month risk is that this becomes a normalization story rather than a secular rerating.

The second-order winner is actually the broader memory complex, with MU the cleaner expression if AI infrastructure spend broadens into DRAM/HBM scarcity. By contrast, SNDK is more exposed to a pure-NAND cycle, where incremental capacity can eventually compress margins faster than investors expect. If memory pricing stays elevated, server BOM inflation could force hyperscalers to ration spend across GPUs, networking, and storage, which would slow the very demand that is driving the thesis.

The key catalyst is the next earnings call: the market will focus less on the trailing margin print and more on whether management can sustain ASPs and backlog into late 2026. What would falsify the bullish case is sequential gross margin compression, softer commentary on customer inventory, or any sign that supply agreements are mostly contractual optics rather than true volume visibility. If spot pricing flattens before the August print, this move is likely overextended and vulnerable to a fast de-rating.

Key Decisions for Investors

• Prefer MU over SNDK on a 1-3 month horizon: long MU / short SNDK as a relative-value memory pair. Rationale: broader product mix and better exposure to durable AI memory content; thesis fails if SNDK keeps >75% gross margins and guides above consensus on Aug. 5.
• Do not chase SNDK outright ahead of earnings. Use a pullback of 10-15% from current levels only if management confirms pricing power and backlog conversion; otherwise the stock is vulnerable to a post-print mean reversion.
• If you want directional exposure to the AI memory theme, own a basket long MU + NVDA versus short SNDK only as a hedge against a NAND-specific reset. This expresses the view that compute and HBM are the more durable AI beneficiaries than commodity storage.
• Set a watch item for NAND spot pricing and hyperscaler capex commentary over the next 4-8 weeks. A rollover in spot prices or softer 2027 capex guidance would be the cleanest early warning to reduce exposure.