According to @StockMKTNewz, the S&P 500 additions since 2023 include Coinbase COIN in May 2025 and Robinhood HOOD in September 2025, alongside Interactive Brokers IBKR and other names through December 2025, source: @StockMKTNewz on X, Dec 6, 2025. For traders, S&P 500 inclusion typically drives mechanical buying from index trackers and benchmarked funds under the S&P U.S. Indices methodology, increasing near-term demand and liquidity around effective dates, source: S&P Dow Jones Indices, S&P U.S. Indices Methodology. Because COIN and HOOD derive meaningful activity from crypto trading per their filings, their inclusion expands index-based ownership of crypto-exposed equities and adjusts the shareholder mix toward passive funds, which is relevant for BTC-linked equity positioning, source: Coinbase 2024 Form 10-K and investor relations overview; Robinhood 2024 Form 10-K.