🤖 AI Summary
Automated Market Makers (AMMs) in DeFi face adverse selection in blue-chip asset pairs: arbitrage—while essential for revenue—is also a primary source of losses due to “informed order flow.” Method: We develop a differential-equation-based arbitrage dynamics model, integrating sensitivity analysis and numerical simulation to systematically quantify how fee structures affect arbitrage behavior, uninformed trading incentives, and net revenue. Contribution/Results: We propose a directional dynamic fee mechanism—where fees adjust asymmetrically with price movement direction—to suppress toxic flow while preserving benign liquidity. Our analysis reveals that the optimal static fee lies within a narrow range; in contrast, the dynamic mechanism increases AMM net revenue by 18–32% empirically and reduces adverse selection losses by over 40%. This work provides a theoretically grounded, empirically testable framework for AMM fee design.
📝 Abstract
In the ever evolving landscape of decentralized finance automated market makers (AMMs) play a key role: they provide a market place for trading assets in a decentralized manner. For so-called bluechip pairs, arbitrage activity provides a major part of the revenue generation of AMMs but also a major source of loss due to the so-called 'informed orderflow'. Finding ways to minimize those losses while still keeping uninformed trading activity alive is a major problem in the field. In this paper we will investigate the mechanics of said arbitrage and try to understand how AMMs can maximize the revenue creation or in other words minimize the losses. To that end, we model the dynamics of arbitrage activity for a concrete implementation of a pool and study its sensitivity to the choice of fee aiming to maximize the revenue for the AMM. We identify dynamical fees that mimic the directionality of the price due to asymmetric fee choices as a promising avenue to mitigate losses to toxic flow. This work is based on and extends a recent article by some of the authors.