
Briefing
The core research problem centers on designing a transaction fee mechanism that aligns incentives for all strategic actors ∞ users, block producers, and colluding parties. This work formally proves an impossibility theorem, establishing that no non-trivial, finite-block-size mechanism can simultaneously satisfy user incentive compatibility, miner incentive compatibility, and collusion-proofness. The foundational breakthrough is the introduction of a relaxed incentive notion, which circumvents this theoretical barrier, allowing for the design of new protocols, such as the “tipless mechanism,” that prioritize specific security properties by explicitly accepting a known trade-off. This new theory fundamentally shifts the focus of blockchain architecture from seeking an ideal mechanism to optimizing the most critical incentive trade-offs for a given system.

Context
The established theory, exemplified by classical auction theory, assumes a non-strategic auctioneer, a premise that fails in a decentralized blockchain environment where the block producer is an active, profit-maximizing participant. The prevailing challenge was the inability of mechanisms like the first-price auction to prevent user misbidding and the known limitations of EIP-1559 in guaranteeing dominant-strategy truthfulness under all demand conditions. This lack of a fully robust mechanism created a foundational theoretical gap, leaving protocols vulnerable to subtle forms of miner manipulation and economic inefficiency.

Analysis
The paper’s core mechanism is a rigorous game-theoretic model that formalizes the strategic interactions between users and block producers. The impossibility result is derived by showing that the requirements for user truthfulness (DSIC) and miner-collusion resistance (OCA-proofness) impose inherently conflicting constraints when block space is limited. The conceptual breakthrough is the tipless mechanism , which achieves Dominant Strategy Incentive Compatibility for users by mandating a fixed base fee burn and eliminating the discretionary “tip” paid to the block producer. This mechanism fundamentally differs from previous approaches by making the inclusion decision independent of the user’s reported value, thereby aligning the user’s incentive to bid truthfully, a property EIP-1559 only approximates.

Parameters
- Impossibility Condition ∞ Simultaneous achievement of MMIC, DSIC, and OCA-proofness is impossible for non-trivial TFMs.
- Tipless Mechanism User IC ∞ Dominant Strategy Incentive Compatible (DSIC).
- EIP-1559 DSIC Guarantee ∞ Only satisfied outside of periods with sudden demand spikes.

Outlook
Future research will focus on formally quantifying the optimal trade-off point between the three core incentive properties, moving beyond the binary impossibility result. The practical application of this theory will unlock a new generation of fee mechanisms in Layer 2 solutions and rollups, allowing architects to explicitly design for either user truthfulness or strong collusion resistance based on the specific security model. This foundational work opens new avenues for mechanism design that integrate cryptographic primitives, such as encrypted mempools, to circumvent the information asymmetry that enables the impossibility result.

Verdict
This research provides the foundational economic impossibility theorem that rigorously defines the inherent incentive trade-offs for all future decentralized transaction fee mechanism design.
