Index change event
S&P 500 Additions & Index Changes: DDOG – 2nd July 2025
On 2 July 2025, S&P Dow Jones Indices announced 2 index changes affecting 2 companies in the S&P 500. Datadog replaced Juniper Networks in the S&P 500.
Announced
2025-07-02
Effective
July 8, 2025 at 5:00:00 PM
Indexes Affected
S&P 500
2
Index Changes in Total
1
Additions
1
Deletions
0
Companies that changed index
What happened to the prices
By the next day's close, Datadog, the only addition with price data, had peaked at +15.53%; the deletion, Juniper Networks, has no usable price data for this date. The moves are measured from the first extended-hours price after the 17:15 ET announcement.
Only Datadog has next-day prices, so there is no group to compare it with: it opened the next day at +8.83% from the first price after the announcement.
In Short
2 index changes: 1 addition and 1 deletion.
No company moved from one S&P index to another in this announcement.
Largest peak move: Datadog, +15.53% by the next day's close.
The changes, index by index
An empty cell means the company was not in the S&P family before, or left it.
S&P 500 Additions: Datadog (DDOG)
1 company joined the S&P 500 and 1 left, effective 9 July 2025. Datadog is new to the S&P family and Juniper Networks left the S&P family. Datadog peaked at +15.53% by the next day's close.
Company | Ticker | Source Index | Final Index | Effective Date |
|---|---|---|---|---|
Datadog | DDOG | S&P 500 | 07/09/2025 |
Company | Ticker | Source Index | Final Index | Effective Date |
|---|---|---|---|---|
Company | Ticker | Source Index | Final Index | Effective Date |
|---|---|---|---|---|
Company | Ticker | Source Index | Final Index | Effective Date |
|---|---|---|---|---|
Price reaction
The close price is the last price before the announcement. All percentages are measured from the open price after the announcement.
S&P 500 Additions Changes
Company | Ticker | Source Index | Final Index | Close Price | Open Price at Announcement | % Change +5 min | % Change +30 min | % Change at 20:00 Hrs | % Change by Next Day Open | % Highest Change by Next Day Close |
|---|---|---|---|---|---|---|---|---|---|---|
Datadog | DDOG | S&P 500 | 135.01 | 135.49 | +7.82% | +8.79% | +10.49% | +8.83% | +15.53% |
S&P MidCap 400 Additions Changes
Company | Ticker | Source Index | Final Index | Close Price | Open Price at Announcement | % Change +5 min | % Change +30 min | % Change at 20:00 Hrs | % Change by Next Day Open | % Highest Change by Next Day Close |
|---|---|---|---|---|---|---|---|---|---|---|
S&P SmallCap 600 Additions Changes
Not a Investment Advice
Company | Ticker | Source Index | Final Index | Close Price | Open Price at Announcement | % Change +5 min | % Change +30 min | % Change at 20:00 Hrs | % Change by Next Day Open | % Highest Change by Next Day Close |
|---|---|---|---|---|---|---|---|---|---|---|
Not a Investment Advice
This page is research about past price behaviour. It is not a recommendation to buy or sell.