Settlement
gas sponsorship
Gas sponsorship means a party other than the token holder pays the blockchain fee for a transaction. In the common x402 pattern the buyer signs an EIP-3009 authorization and the facilitator submits it, so the buyer does not need the chain's native gas token. That is not the same design as a chain that prices gas itself in USDC.
Explanation
On Base, Polygon, and similar EVM chains, the facilitator transaction pays gas in the chain's fee token. The USDC amount of the payment is separate from that fee. A fee the facilitator takes in USDC can appear as its own transfer and is treated as raw volume, not as gas. On Arc, the documented native gas token is 18-decimal USDC. This index does not count those gas movements as payments.
ERC-4337 paymasters are another sponsorship mechanism: a smart wallet submits a UserOperation and a paymaster covers the fee under its own policy. Circle's Gateway nanopayment docs say the buyer signs offchain and Gateway batches settlement, and that this path checks EIP-3009 signatures rather than ERC-1271. Sponsorship removes a fee from the payer. It does not decide whether the payment is in Agent GDP. The settlement rule does.
Live data
Related terms
Sources
- EIP-3009: Transfer With Authorization — Ethereum Improvement Proposals
- How x402 works — Coinbase Developer Platform
- ERC-4337: Account Abstraction Using Alt Mempool — Ethereum Improvement Proposals
- Nanopayments — Circle
- Connect to Arc — Arc