The x402 Foundation — formed by Coinbase, Cloudflare, and Stripe to govern an open standard for AI-native payments — announced Thursday it is joining the Linux Foundation, the nonprofit hub for open-source software development. The move brings a wide coalition of major companies into the fold, with early participants including Adyen, Amazon Web Services, American Express, Google, Mastercard, Microsoft, Shopify, Visa, Circle, and the Solana Foundation, among others.

x402 is built for agentic commerce: high-frequency microtransactions executed autonomously by AI agents that legacy payment networks aren’t designed to handle. The protocol revives the long-dormant HTTP 402 “Payment Required” status code, allowing servers to respond with payment terms, clients to settle in stablecoins like USDC, and the request to automatically retry once payment is confirmed — all without accounts, subscriptions, or manual invoicing.

This story is an excerpt from the Unchained Daily newsletter.

By joining the Linux Foundation, the x402 Foundation is positioning the protocol as a vendor-neutral open standard, licensed under Apache 2.0 with no protocol fees and no vendor lock-in. Linux Foundation CEO Jim Zemlin framed the goal as building a payments layer as open as the internet’s foundational protocols.

The announcement places x402 in direct competition with the Machine Payments Protocol, a rival standard co-created by Stripe and crypto venture firm Paradigm and backed by OpenAI, Anthropic, Visa, and Deutsche Bank. Stripe is hedging by participating in both consortia. x402 has processed roughly 97 million transactions through Coinbase’s Base blockchain to date, though daily transaction volumes remain modest — around 54,900 per day earlier this week.