Block has joined the Linux Foundation-governed x402 Foundation and said it will add Bitcoin Lightning Network support to x402, an open payment protocol for AI agents, web services and applications. Cointelegraph reported the development on September 25, following Block's September 24 announcement of its participation and a September 23 repository commit documenting Lightning support through the lnbtc network identifier. Block says Lightning is suited to fast, low-cost and repeated small payments, a model it views as relevant to AI-agent commerce. Steve Lee, head of Spiral, Block's Bitcoin development initiative, described the integration as a step toward using Bitcoin for everyday payments by people and AI agents. x402 lets software autonomously pay for API access, data and digital services through HTTP 402 Payment Required responses. The x402 Foundation was launched under the Linux Foundation in April, and its participants include Google, Microsoft, Amazon Web Services, Coinbase and the Solana Foundation. Block also participates in the Universal Commerce Protocol project, which supports AI-driven commerce for small businesses.