Western Digital Beat on Everything and Still Fell 16%. Its Storage Rival SanDisk Had the Same Day

Western Digital reported fiscal fourth-quarter 2026 results on August 5, 2026 that beat on every headline metric: non-GAAP earnings per share of $3.56 against a $3.35 estimate, up 109% year over year and 31% sequentially, exceeding even the high end of management's own prior guidance range. Revenue of $3.75 billion surged 44% year over year and beat the $3.70 billion consensus estimate. The Cloud segment, which makes up 89% of total revenue, climbed 43% to $3.3 billion, driven by demand for higher-capacity nearline drives and a favorable pricing environment — the core engine behind the beat.

Despite that, shares fell roughly 5.4% in the regular session to close at $519.17, then dropped a further 11.1% in after-hours trading to $461.42 — a total decline of roughly 16% around the print. A stock falling this hard on a clean beat is a guidance story, not a results story: when every reported number is strong but the shares still drop double digits, the market is almost always reacting to what management said about the quarter ahead, not the quarter just delivered.

The context that makes this more than a single-company story: the same day, fellow storage and memory maker Sandisk also beat its own Q4 estimates on revenue and EPS, and also fell on guidance concerns. Two large-cap storage suppliers beating current-quarter numbers and both selling off on forward guidance, on the same day, points to a market-wide read on the storage and memory pricing cycle rather than something specific to either company's execution. When peer companies react the same way to similar news, that is generally a sector-level repricing of expectations, not a coincidence.

A beat this large paired with a drop this large typically signals the market believes current pricing and demand conditions represent the peak, or close to the peak, of the current cycle — making the trajectory implied by guidance, rather than the trailing quarter's record results, the dominant input to how the stock is valued from here.