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Maximal Extractable Value

Extra value a block producer can capture by choosing how to order or include transactions.

Maximal Extractable Value (MEV) refers to additional value a block producer can capture by strategically choosing which transactions to include, exclude, or reorder within a block, beyond standard fees and rewards.

Common examples include front-running a profitable trade or inserting transactions around a large trade to profit from its price impact (see Kaavon's "Front-Running" and "Sandwich Attack" glossary definitions for these two specific, named techniques) — practices that can affect ordinary users' transaction outcomes.

Examples

A large decentralized exchange trade can attract MEV activity from parties trying to profit off its price impact.
Some infrastructure has been built specifically to reduce or redistribute MEV more fairly.