Shares of Sandisk surged past $1,800 on September 21, building on a blistering 17%+ run in just four trading sessions, as the memory-chip maker officially joined the S&P 100 index before Monday's open. The inclusion crowns a remarkable stretch for a company that was spun off from Western Digital only last year — but investors now face the question of how much of the good news is already priced in. Sandisk Enters the S&P 100 Blue-Chip Club on a Monster Rally — But at 24 Times Earnings, How Much Upside Is Left?
Shares of Sandisk climbed to $1,803.38 Monday morning, extending a jaw-dropping 17%-plus surge over four trading days, as the memory-chip maker officially took its seat in the S&P 100 index before the opening bell. SNDK joined alongside Dell Technologies, Palo Alto Networks, and Arista Networks, replacing legacy blue chips including Nike, Honeywell Aerospace, and Colgate-Palmolive. For shareholders, the question now is whether the forced buying that comes with index membership can sustain a stock that has already priced in a lot of good news.
Index Funds Now Must Own Sandisk — And That Creates a Built-In Buyer
S&P 100 inclusion forces passive funds and index products that track the benchmark to buy SNDK, often over multiple days around the rebalance date. That mechanical demand matters: the steady bid can narrow trading spreads, deepen liquidity, and support the stock even on choppy sessions.
Institutional investors were already piling in — 128 hedge funds held positions in Q2, up from 114 in Q1 — and BlackRock alone built a roughly $23.4 billion new position in the second quarter. The S&P 100 stamp will only accelerate that flow.
AI-Driven NAND Scarcity Is the Real Profit Engine
Index inclusion is a visibility event; the earnings story is what matters long-term. AI data centers require enormous amounts of NAND flash storage, and SanDisk is a primary supplier of enterprise solid-state drives feeding that buildout.
TrendForce says enterprise SSD orders show no sign of slowing and meaningful NAND capacity expansion is unlikely until late 2027 or 2028. That supply squeeze is showing up in the numbers: fiscal 2026 revenue hit $20.25 billion , and non-GAAP gross margins reached 84.6% in the fiscal fourth quarter.
The Valuation Is Getting Crowded
At ~24 times earnings, the stock is not cheap for a cyclical memory company. Analysts' average 12-month target sits near $2,125 — roughly 18% above today's price — but that assumes the current supercycle holds. SNDK trades at premium multiples and is tied to broader AI and data-center sentiment , meaning any slowdown in AI spending or a shift in memory pricing could cut the stock hard.
Insider Sales Add a Footnote of Caution
SEC filings show Sandisk's chief technology officer sold shares in early September under a pre-arranged trading plan, disposing of blocks at prices around $1,513–$1,538. Pre-planned sales aren't necessarily bearish, but they remind investors that executives are locking in gains while the market is hot.
Bottom line: The S&P 100 promotion is a structural positive for demand, but at these multiples, Sandisk's price already reflects a best-case NAND cycle. The next catalyst will be whether margins hold — not whether index funds keep buying.