The S&P 500 index is a broad-market benchmark that programmatically weights ~500 of the largest publicly traded U.S. companies by market capitalization. It is the basis for trillions of dollars in passive and active investment strategies.

On May 19, Coinbase became the first crypto stock to be included in the index; its addition was estimated to have triggered $15B in inflows for the stock and means that roughly 0.11% of every dollar flowing into S&P 500-linked portfolios is now allocated to the crypto exchange.

While this amount might seem modest, the sheer scale of the index translates that fraction into multi-million dollar buys every month as investors allocate to the passive strategy, a valuable support mechanism for COIN’s price and liquidity that signals crypto’s deepening ties with traditional finance.