Sandisk's Revenue Tripled and It Still Beat Estimates — Then Fell on Guidance the Same Day Western Digital Did

Sandisk reported fiscal fourth-quarter 2026 results on August 5, 2026 that beat on both headline metrics by a wide margin: revenue of $8.97 billion, up 372% year over year and above the roughly $8.42 billion analysts expected, with a record gross margin, and adjusted earnings per share of $39.25 against a $34.59 consensus estimate — a beat of roughly 14%. The scale of the year-over-year revenue growth reflects the ongoing NAND flash pricing rally that has lifted the whole memory sector through 2026.

The stock still fell, and the reason was forward guidance rather than the results just reported. Sandisk guided fiscal first-quarter 2027 revenue to a range of $10.3 billion to $10.8 billion; the midpoint of that range came in below the roughly $10.82 billion Wall Street had modeled. A guidance midpoint landing under the estimate, even a modest shortfall, is enough to override a large trailing-quarter beat when a stock's valuation already prices in continued acceleration — investors weighed the pace of the NAND rally's next leg more heavily than the record results just delivered.

The context that makes this more than a single-company story: the same day, fellow storage and memory maker Western Digital also beat its Q4 estimates on revenue and EPS by a wide margin, and also fell — roughly 16% between the regular session close and after-hours trading — on its own guidance concerns. Two large-cap storage suppliers beating current-quarter numbers decisively and both selling off on forward guidance, on the same day, is a sector-level read on where the NAND and hard-drive pricing cycle goes next, not a coincidence tied to either company's individual execution.

A beat this large paired with a decline on guidance typically signals the market believes current pricing and demand conditions are close to the cycle's peak — making the growth rate implied by guidance, not the record quarter already reported, the dominant input to how both stocks are being valued from here.