
Briefing
The core research problem addresses the economic insecurity of current Transaction Fee Mechanisms (TFMs), specifically EIP-1559, which are susceptible to a miner extracting additional revenue by coercively running a separate, off-chain auction and threatening to censor on-chain transactions. The foundational breakthrough is the introduction of a new, necessary desideratum for TFM design ∞ Off-Chain Influence Proofness , which demands that the block producer cannot increase their revenue by influencing users off-chain. The paper proposes a modified Cryptographic Second-Price Auction that allows the miner to set an on-chain reserve price, a mechanism proven to align the miner’s revenue-maximizing strategy with the transparent, on-chain protocol. This new theory fundamentally redefines the theoretical boundary of incentive-compatible blockchain design, proving that achieving a truly influence-proof TFM requires a shift from simple, non-cryptographic designs to more complex, cryptographically-assisted auction primitives.

Context
The established theory of transaction fee mechanism design centered on achieving simplicity for users and miners, along with resistance to collusion, with EIP-1559 becoming the gold standard for its predictable base fee and burning mechanism. The prevailing theoretical limitation, however, was the failure to account for the miner’s ability to exert influence outside the protocol’s defined boundaries. This created a foundational academic challenge where the on-chain mechanism’s game-theoretic properties were undermined by the reality of off-chain side-contracts and censorship threats, revealing a critical gap in the security model.

Analysis
The core mechanism proposed is a Cryptographic Second-Price Auction (C2PA) augmented with a miner-set reserve price. Conceptually, users submit their true valuations as encrypted bids, ensuring their privacy and preventing front-running. The block proposer’s sole strategic action is to publicly declare a reserve price on-chain, which is the minimum acceptable fee.
The cryptographic protocol then executes the auction ∞ the winning transaction pays the minimum of the second-highest bid and the miner’s reserve price. This design fundamentally differs from previous approaches by transforming the miner’s off-chain influence incentive into an on-chain, transparent, and revenue-maximizing action, thereby cryptographically enforcing the desired economic equilibrium.

Parameters
- Off-Chain Influence Proofness ∞ No known TFM satisfies this new desideratum alongside all previous TFM properties.

Outlook
The immediate next step in this research area is the practical implementation and performance benchmarking of the Cryptographic Second-Price Auction mechanism, likely leveraging existing multi-party computation or zero-knowledge proof primitives to handle the encrypted bids. In the next three to five years, this theory is poised to unlock a new generation of fee mechanisms for Layer 2 rollups and decentralized sequencers, where the primary goal is credibly neutral and fair transaction ordering. The research opens new avenues for formally proving the economic security of decentralized systems against sophisticated, cross-layer attacks that exploit the boundary between on-chain and off-chain influence.

Verdict
This research introduces a critical new security primitive that formally redefines the necessary economic properties for any credibly neutral blockchain transaction fee mechanism.
