Shares of Robinhood Markets (HOOD) and AppLovin (APP) surged on Monday after S&P Dow Jones Indices said the companies will join the S&P 500 index later this month, replacing Caesars Entertainment and MarketAxess Holdings.
Robinhood climbed about 8% and AppLovin rose nearly 9% in early trading. Both stocks have outperformed the broader market in 2025, buoyed by strong earnings and investor demand for high-growth technology and trading platforms.
The additions will take effect prior to the market open on Sept. 22. Inclusion in the S&P 500, tracked by trillions of dollars in passive investment funds, typically drives buying pressure as index funds adjust holdings to match the benchmark.
Caesars Entertainment will be moved to the S&P MidCap 400, while MarketAxess Holdings will drop to the S&P SmallCap 600, according to the index provider.
Robinhood, once known for catering to retail traders during the pandemic-era boom, has broadened its business into wealth management and crypto trading. AppLovin, a software firm focused on mobile app monetization and game development, has seen a sharp rise in revenue from artificial intelligence-powered advertising tools.
The reshuffle underscores how index operators adjust for market capitalization shifts and sector performance. Both Robinhood and AppLovin have more than doubled in value this year, while Caesars and MarketAxess have lagged.