This price action reflects the well-documented "index effect,†where trillions of dollars in passive index funds and ETFs must purchase shares of newly added companies to maintain accurate tracking of the benchmark. For fund managers overseeing S&P 500-indexed portfolios, purchasing Sandisk stock is not discretionary but mandatory, creating a massive and predictable wave of institutional demand. The market has quickly priced in this expected buying pressure from some of the world's largest institutional inve ...

Companies usually see a bump in their share price when included on a stock index. That didn't happen this time.According to data compiled by S&P Global Market Intelligence, Nano Nuclear Energy's (NNE -2.79%) share price had eroded by almost 11% week to date as of Thursday night. This, despite the fact that the company was included on several stock indexes managed by a well-known indexer.Come and joinBefore market open that day, Nano announced that its stock is now a component of not one, not two, but three ...

Core Viewpoint - Datadog's stock surged significantly after the announcement that it will be added to the S&P 500 index, replacing Juniper Networks, which was acquired by Hewlett Packard Enterprise [1][3]. Group 1: Index Inclusion - Datadog will join the S&P 500 index before trading starts on July 9, marking a significant milestone for the company [3]. - The inclusion in the S&P 500 is seen as a validation of Datadog's market position, especially as it was chosen over other popular stocks like AppLovin and Robinhood Markets [3][4]. - The S&P 500 is regarded as the most reliable benchmark for stock market performance in the U.S., and companies must meet stringent criteria to be included [4]. Group 2: Market Reaction - Following the announcement, Datadog's stock rose by 13.1% within the first hours of trading [1]. - Stocks that join indices like the S&P 500 often experience a short-term price increase due to the "index effect," where index funds and ETFs buy shares to adjust their portfolios [5]. - Historical data indicates that while the initial price bump is common, long-term performance will depend on factors such as revenue growth and profitability [5]. Group 3: Company Performance and Future Outlook - Datadog has been recognized as a Leader in the "2024 Magic Quadrant" by Gartner for observability platforms, indicating strong market positioning [6]. - The company has adapted its offerings to include tools for monitoring large language models (LLMs) and AI systems, which currently contribute approximately 9% to its annual recurring revenue [6]. - Given the company's growth trajectory and the favorable trends in AI, there is potential for continued investor interest in Datadog [7].