In the rapidly evolving world of Ethereum, a silent power shift is taking place — and it's happening in the shadows of the blockchain. A new research paper has exposed the rising centralization in Ethereum’s Maximal Extractable Value (MEV) practices, where a handful of players are tightening their grip on how transactions are ordered and profits extracted.
At the center of this issue are so-called “searchers” — specialized arbitrageurs who profit by manipulating the order of transactions within blocks. According to the study, titled “Measuring CEX-DEX Extracted Value and Searcher Profitability: The Darkest of the MEV Dark Forest,” many of these searchers are either in-house operators or work under exclusive contracts with MEV builders, the entities that construct blocks for the Ethereum network.
MEV refers to the extra revenue earned by reordering, inserting, or excluding transactions in a block before finalization. This often includes high-frequency strategies such as arbitrage, front-running, and sandwich attacks — where large traders exploit smaller users’ transactions for quick profits. The study particularly focuses on how these searchers exploit price discrepancies between centralized exchanges (CEXs) and decentralized exchanges (DEXs), profiting at the expense of retail traders.
Alarmingly, the paper identifies three MEV builders — beaverbuild, Titan, and rsync — as dominating Ethereum’s block-building process. Two of these are vertically integrated with their own in-house searchers, giving them an outsized advantage. This consolidation is triggering serious concerns around decentralization, as it strengthens the dominant players' grip on profits and block production. With scale, they can enforce monopoly-like pricing, cause losses for block proposers, and increase the risk of censorship or manipulation.
The researchers argue that this vertical integration not only undermines fairness but also poses threats to Ethereum’s long-term security. They warn that these “centralization pressures” must be addressed when considering the future development of Ethereum as a decentralized layer-1 platform.
Ethereum’s current system — known as Proposer-Builder Separation (PBS) — was designed to enhance censorship resistance by allowing block proposers to outsource block construction. Yet, critics say PBS has unintentionally centralized control in the hands of a few builders and has skewed the playing field against smaller participants.
In fact, a staggering 80% of all Ethereum blocks are now proposed by just two entities. This alarming statistic has prompted calls from within the Ethereum community for change. Pseudonymous researcher Malik672, for example, recently suggested democratizing block building to allow thousands of contributors instead of a select few.
Ethereum co-founder Vitalik Buterin has also weighed in on the MEV debate, advocating for solutions that reduce MEV’s influence altogether. His proposals include rethinking infrastructure such as exchanges and finding ways to limit the access arbitrageurs have to onchain data — cutting off the fuel they use for their advanced strategies.
As Ethereum moves toward scaling and evolving its ecosystem, the centralization of MEV practices represents a serious challenge. Without meaningful intervention, the network risks slipping further from its decentralized ideals — making it imperative to rethink how value is extracted, who holds the power, and how fairness is maintained on the chain.$ETH
