{"id":89606,"date":"2023-08-04T12:59:45","date_gmt":"2023-08-04T12:59:45","guid":{"rendered":"https:\/\/www.techopedia.com\/?post_type=definition&p=89606"},"modified":"2023-08-04T12:59:45","modified_gmt":"2023-08-04T12:59:45","slug":"maximal-extractable-value-mev","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/maximal-extractable-value-mev","title":{"rendered":"Maximal Extractable Value (MEV)"},"content":{"rendered":"
Maximal extractable value (MEV) is the maximum profit that blockchain<\/a> miners and validators can make by including, excluding, and changing the order of transactions in a block.<\/p>\n MEV was initially an abbreviation for \u2018miner extractable value\u2019 when the two biggest public blockchains in the world \u2013 Bitcoin<\/a> and Ethereum<\/a> \u2013 relied on proof-of-work<\/a> (PoW) miners<\/a> to validate transactions and create new blocks. It changed to \u2018maximal extractable value\u2019 after Ethereum\u2019s move to proof-of-stake<\/a> (PoS) as mining is no longer part of the protocol.<\/p>\n Though it is important to note that MEV practices are not exclusive to Bitcoin and Ethereum \u2013 they are practiced in alternative blockchains, too, such as Binance Smart Chain<\/a> (BSC) and Solana.<\/p>\n MEV is a controversial subject that has both positive and negative effects on the blockchain network. MEV practices can fix economic inefficiencies in decentralized applications<\/a> (dApps) but can also lead to high gas fees<\/a> and poor user experience.<\/p>\n To understand the definition of maximal extractable value (MEV), you need to know how miners and validators perform their basic functions on a blockchain.<\/p>\n Miners and validators are block producers who are responsible for batching pending transactions to a block. Each time a user transacts on the blockchain, they pay a transaction fee called a gas fee to the block producer.<\/p>\n Each block can only fit in a limited number of transactions. Typically, block producers prioritize transactions with the highest gas price in order to maximize their profits. Users can choose to pay higher gas fees to ensure that their transactions are included in the upcoming block.<\/p>\n It should be noted that block producers have full autonomy on the transactions to include in the upcoming block. As the pending transactions are visible to everyone in the mempool, block producers can pick and choose from thousands of pending transactions to extract the maximum value from a block.<\/p>\n There are players other than validators and miners in the MEV game. According to Ethereum.org<\/a>, a large portion of MEV is extracted by independent network participants referred to as “searchers.”<\/p>\n Searchers implement elaborate algorithms to detect MEV opportunities and use bots to automatically submit those transactions to the network. These MEV opportunities can range from decentralized exchange<\/a> (DEX) arbitrage to loan liquidations.<\/p>\n The competition can be very high for certain lucrative MEV opportunities. During such a time, a searcher may pay gas fees as high as 90% of the MEV revenue to ensure that their transaction is executed before the competition. Validators and miners will always get a portion of the MEV as searchers pay high gas fees to ensure transaction finality.<\/p>\n In the table below, we review a few examples of MEV opportunities.<\/p>\nHow Does MEV Work?<\/span><\/h2>\n
MEV Examples<\/span><\/h2>\n