Datadog Inc. will be added to the S&P 500 index, replacing Juniper Networks, which is being acquired by Hewlett Packard Enterprise. The change will take effect before the market opens on July 9, 2025. Following the announcement, Datadog's stock surged in after-hours trading, rising more than 10% and reaching prices around $147.95. The inclusion reflects a rebalancing of the index due to Juniper Networks' acquisition by Hewlett Packard Enterprise. Market analysts and investors have noted increased bullish activity in Datadog's shares ahead of the official inclusion date.