MEV Bots Consume Over Half of Ethereum L2 Gas Fees
Maximal Extractable Value (MEV) bots are now burning more than 50% of all gas fees on Ethereum Layer 2 networks, siphoning millions and creating an economic bottleneck. This activity highlights how a lack of transactional privacy is evolving from a philosophical concern into a direct threat to scaling and fair market access for users.
- Much of the high gas consumption is driven by "optimistic MEV," where bots engage in speculative on-chain probing for arbitrage opportunities. This activity, mainly consisting of "interaction probes," keeps blocks on networks like Base and Optimism persistently full. - In the first quarter of 2025, cyclic arbitrage bots accounted for 55% of gas usage on Optimism, 51% on Base, and 7% on Arbitrum. However, despite consuming over half the gas on Base and Optimism, these bots paid less than a quarter of the total gas fees. - This MEV activity is highly concentrated, with two searcher bots being responsible for over 80% of the "spam" on Base. The dominant strategy involves submitting many small transactions to probe for opportunities, accepting a high failure rate in exchange for occasional profits. - The low-fee environment on L2s, particularly after the Dencun upgrade, has intensified this behavior, leading to a spike in reverted swap transactions and an increase in duplicated spam transactions by bots. - To combat harmful MEV like front-running and sandwich attacks, L2s are exploring solutions such as encrypted mempools, which hide transaction contents until they are finalized. Other strategies include private order flow, fair sequencing services (FSS), and commit-reveal schemes. - The centralized nature of sequencers on many L2s is a key factor, as a single entity has the power to order transactions, which can be exploited for MEV. Decentralizing sequencers through mechanisms like MEV-Auctions (MEVA) or shared sequencer networks is a proposed long-term solution. - R&D organization Flashbots is developing SUAVE (Single Unifying Auction for Value Expression), a project aimed at decentralizing the block builder role and creating a universal, privacy-focused mempool that can serve multiple blockchains. - The total value extracted by MEV remains significant; on Ethereum mainnet, nearly $24 million in MEV profit was extracted in the 30-day period from December 8, 2025, to January 6, 2026.
