Four sources familiar with the plans told CoinDesk that Coinbase is preparing its trading rails for Solana ecosystem tokens. According to the sources, the US-based crypto exchange wants to accept withdrawals of SPL tokens, or "Solana Program Library" tokens — Solana's response to Ethereum's ERC-20. USDC, which is based in Solana and has a circulating supply of $4.8 billion, is one among the assets that will be maintained, according to one source.