Liquidation Dynamics in DeFi and the Role of Transaction Fees

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Sadeghi, Agathe, Feinstein, Zachary
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866912900724031488
author Sadeghi, Agathe
Feinstein, Zachary
author_facet Sadeghi, Agathe
Feinstein, Zachary
contents Liquidation of collateral are the primary safeguard for solvency of lending protocols in decentralized finance. However, the mechanics of liquidations expose these protocols to predatory price manipulations and other forms of Maximal Extractable Value (MEV). In this paper, we characterize the optimal liquidation strategy, via a dynamic program, from the perspective of a profit-maximizing liquidator when the spot oracle is given by a Constant Product Market Maker (CPMM). We explicitly model Oracle Extractable Value (OEV) where liquidators manipulate the CPMM with sandwich attacks to trigger profitable liquidation events. We derive closed-form liquidation bounds and prove that CPMM transaction fees act as a critical security parameter. Crucially, we demonstrate that fees do not merely reduce attacker profits, but can make such manipulations unprofitable for an attacker. Our findings suggest that CPMM transaction fees serve a dual purpose: compensating liquidity providers and endogenously hardening CPMM oracles against manipulation without the latency of time-weighted averages or medianization.
format Preprint
id arxiv_https___arxiv_org_abs_2602_12104
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Liquidation Dynamics in DeFi and the Role of Transaction Fees
Sadeghi, Agathe
Feinstein, Zachary
Mathematical Finance
Dynamical Systems
Trading and Market Microstructure
91G80, 90C39
G.1.6; I.6.3
Liquidation of collateral are the primary safeguard for solvency of lending protocols in decentralized finance. However, the mechanics of liquidations expose these protocols to predatory price manipulations and other forms of Maximal Extractable Value (MEV). In this paper, we characterize the optimal liquidation strategy, via a dynamic program, from the perspective of a profit-maximizing liquidator when the spot oracle is given by a Constant Product Market Maker (CPMM). We explicitly model Oracle Extractable Value (OEV) where liquidators manipulate the CPMM with sandwich attacks to trigger profitable liquidation events. We derive closed-form liquidation bounds and prove that CPMM transaction fees act as a critical security parameter. Crucially, we demonstrate that fees do not merely reduce attacker profits, but can make such manipulations unprofitable for an attacker. Our findings suggest that CPMM transaction fees serve a dual purpose: compensating liquidity providers and endogenously hardening CPMM oracles against manipulation without the latency of time-weighted averages or medianization.
title Liquidation Dynamics in DeFi and the Role of Transaction Fees
topic Mathematical Finance
Dynamical Systems
Trading and Market Microstructure
91G80, 90C39
G.1.6; I.6.3
url https://arxiv.org/abs/2602.12104