S&P announces major changes in S&P 100, S&P 500, S&P 400
S&P Dow Jones Indices announced changes to its major indices. Sandisk (SNDK) will join the S&P 100, replacing Colgate-Palmolive (CL). Other additions to the S&P 100 include Dell (DELL), Palo Alto Networks (PANW), and Arista Networks (ANET). The S&P 500 will add Bloom Energy (BE), Illumina (ILMN), and Everpure (P). Changes are effective before trading on Sept. 21, 2026.
How this was made
The 30-second read
Why it matters
The changes will trigger fund rebalancing, creating short‑term buying pressure for additions and selling pressure for removals.
Market read
Index composition changes affect a wide range of passive funds and can move individual stocks around the rebalance dates.
What to watch
Liquidity of smaller caps and tax considerations for fund managers could moderate price impact.
Background
S&P Dow Jones Indices announced its quarterly rebalance, adding and removing several U.S. stocks across the S&P 100, 500, and MidCap 400.
Ticker impact
Added to the S&P 100, likely increasing demand for the stock in index funds.
Modest upside as ETFs rebalance.
Inclusion in a major index typically lifts price due to fund flows.
Added to the S&P 100, boosting exposure in index-tracking products.
Small upside ahead of rebalance date.
Index inclusion drives buying pressure.
Added to the S&P 100, increasing passive‑investment demand.
Modest upside before Sept 21.
Index addition creates buying pressure.
Added to the S&P 100, attracting index‑fund inflows.
Small upside around rebalance.
Inclusion in a major index typically benefits price.
Removed from the S&P 100, potentially reducing passive‑fund demand.
Modest downside before removal date.
Loss of index status can trigger selling.
Removed from the S&P 100, may see reduced index‑fund buying.
Minor downside near rebalance.
Removal reduces passive demand.
Removed from the S&P 100, could face lower index‑fund inflows.
Small downside before effective date.
Index exclusion typically depresses price.
Added to the S&P 500, increasing exposure in broad market funds.
Modest upside as ETFs rebalance.
S&P 500 addition drives buying.
Market effects
Broad index rebalancing may shift sector weightings, affecting sector ETFs.
U.S. equity markets may see modest volatility around rebalance dates.
International investors tracking S&P indices will adjust holdings accordingly.
Counterpoint
Some investors may short newly added stocks anticipating short‑term profit‑taking.
Key entities
- OrganizationS&P Dow Jones Indices
Index provider announcing the rebalance.
