The emergence of 'private rooms' in Wall Street's trading landscape is drawing attention as an even more exclusive method for buying and selling stocks, further darkening the already opaque world of dark pools. Dark pools, which currently handle approximately 60% of U.S. trading volume, are being challenged by new developments in decentralized finance (DeFi) on the Solana blockchain. Companies like Arcium are leading this shift, promising a fundamental change in on-chain trading with fully trusted and encrypted privacy solutions. As the trading environment evolves, the implications for market participants and the future of capital markets are significant.