SanDisk to join the S&P 500 as Strategy misses out again

SanDisk Corp. is set to enter the S&P 500 on Friday, capping a remarkable period of rapid growth and surprising some investors who had anticipated a different outcome.

S&P Dow Jones Indices announced the move late Monday, sending SanDisk shares up more than 7% in extended trading and more than 13% during the regular session.

The company will replace Interpublic Group of Companies Inc. in the benchmark index, shifting out of the S&P SmallCap 600, where its $33 billion market capitalization had long made it an outlier.

The timing of the inclusion, taking effect at the open of a Thanksgiving holiday–shortened session, marks an unusual deviation from the index provider’s typical quarterly rebalancing schedule.

Expectations had centered on early December for the next reshuffle, but the committee opted to act sooner, underscoring the strength of SanDisk’s recent momentum.

SanDisk’s meteoric rise amid AI demand

SanDisk’s ascent into the S&P 500 reflects its dramatic surge in valuation, driven by swelling demand for storage solutions tied to artificial intelligence infrastructure.

The stock has gained nearly 400% in the past three months, fueled by optimism around machine learning adoption and the critical role storage hardware plays in supporting increasingly data-hungry AI models.

This explosive growth pushed SanDisk well beyond small-cap status, making its move into the large-cap index a logical progression.

Inclusion in the S&P 500 typically brings a wave of passive inflows from index-tracking funds and heightened interest from institutional investors who benchmark against the index or have mandates restricting holdings to large-cap constituents.

For SanDisk, the shift represents both enhanced visibility and increased liquidity.

The decision to elevate the company ahead of the expected schedule highlights the discretion S&P Dow Jones Indices retains in its methodology.

The committee has demonstrated flexibility in the past, including opting to forgo changes entirely in certain quarters.

In this case, SanDisk’s market performance appears to have prompted a faster-than-anticipated adjustment.

Strategy’s ongoing battle with index standards

While SanDisk celebrates its promotion, Strategy Inc., formerly MicroStrategy, once again fell short of securing a place in the S&P 500 despite meeting several technical criteria.

The enterprise software firm has attracted global attention for holding more than 640,000 Bitcoin, a position valued at more than $72 billion.

Yet the same Bitcoin-heavy strategy that defines the company has become a sticking point for the index committee.

Analysts had estimated a 70% chance for Strategy’s inclusion in December following strong third-quarter earnings.

The company posted $3.8 billion in Q3 profit, but its results remain tethered to Bitcoin price movements, creating significant quarter-to-quarter volatility.

S&P 500 eligibility requires four consecutive quarters of positive earnings, a hurdle that Strategy has not consistently met.

The S&P gave a "B-" credit score for Strategy, showing concerns about its concentrated crypto exposure, limited liquidity in US dollars, and narrow business model.

These issues highlight a deeper philosophical divide between traditional index construction and emerging digital-asset-centric corporate strategies.

While other companies with crypto exposure, such as Robinhood, have earned spots in the index, Strategy’s unprecedented dependence on Bitcoin continues to test the boundaries of existing methodologies.