Block Integrates Bitcoin Lightning into x402 Payment Standard

The integration, visible in a September 23 repository commit titled "exact Lightning on lnbtc," allows developers to use Bitcoin's Layer 2 network as an alternative to existing payment rails. While the x402 protocol has historically relied on stablecoins—with Circle reporting that USDC accounted for 99.3% of volume in the second quarter—the addition of Lightning provides a settlement option native to the Bitcoin network. Steve Lee, head of Block’s Bitcoin development initiative Spiral, noted that the infrastructure is being prepared for a future where autonomous agents perform billions of small, frequent payments.

Expanding the x402 Ecosystem

Originally developed by Coinbase before moving to the Linux Foundation in April, x402 uses the HTTP 402 "Payment Required" response to negotiate transactions between servers and software agents. The protocol currently reports significant activity, with 75.41 million transactions and $24.24 million in volume recorded over the previous 30 days. Block’s involvement aligns with its broader focus on "agentic commerce," which includes its open-source AI agent, Goose, and participation in the Universal Commerce Protocol. Although Block has not provided a specific timeline for deploying Lightning-based x402 payments into its consumer-facing products like Cash App or Square, the company confirmed it will continue contributing to the Foundation’s working groups to refine the standard for large-scale machine-to-machine commerce.