According to @MilkRoadDaily, Robinhood Markets (HOOD) will be added to the S&P 500 effective Sept 22, marking a notable milestone for the brokerage, source: @MilkRoadDaily on X. For trade execution planning, S&P 500 index-tracking funds typically adjust holdings to include new constituents on or around the effective date, which can drive mechanical demand and concentrated closing-auction activity, source: S&P Dow Jones Indices. For crypto-focused market participants, Robinhood also offers crypto trading in assets such as BTC and ETH, making the development relevant when monitoring equity proxies for retail trading engagement, source: Robinhood Crypto.