Ethereum's draft PR 12664 would let block builders include selected sponsored transactions under one shared proof, a proposed change to how the network checks payment claims.
Marchhill filed the proposal on Nov. 13. Each transaction would retain its nonce and receipt, with payment matching checked during finalization. Builders could choose any valid subset of the covered transactions for a block without asking users for new signatures.
PR 12664 would enable the LEANSTARK_SCHEME identifier reserved by EIP-8288. The draft relates to a broader EIP-8288 proof-aggregation proposal, which describes combining declared proof or signature dependencies into a recursive STARK. PR 12664 focuses on payment claims from sponsored transactions.
The PR summary lists provisional charges of 3,000 gas for native signature checks, 30,000 gas for generic proof checks and 2,700 gas in intrinsic proof share per declaration. The filing says those values still need calibration.
In a Nov. 14 comment, Marchhill said sponsors already fund leaf-proof generation off-chain. Builders can account for their proving work through priority fees, the comment said.
Testing across machines and under full inclusion-list workloads remains outstanding, according to the filing. The draft remains unassigned an EIP number and discussion thread, and has not been adopted as an Ethereum upgrade. It gives no mainnet activation date or scheduled decision.
