With the transition of the Ethereum cryptocurrency to POS mining, a real threat arose of centralization of the entire network, when most validators could simply not process transactions from some addresses. Thus blocking the assets on this wallet. Moreover, this method is achieved not only by launching controlled servers with validators, which is extremely expensive, but also by launching special services that increase the income of validators, the so-called MEV BOOST relays. And also with the help of liquid staking (Lido, rocket pool), which also adhere to the AML policy and OFAC sanctions lists (US Office of Foreign Assets Control)
MEV BOOST is special software that selects transactions with the highest commission from the mempool and offers them to validators for signing and recording in the blockchain. At the same time, the validator receives increased profitability from POS mining. It seems that this is a profitable cooperation, but the owners of MEV BOOST Reley began to implement in their algorithms the exclusion of transactions from addresses that OFAC considers unreliable or simply comply with US sanctions.
To make it clearer to you how the MEV BOOST mechanism works, read the article: What is MEV-boost in mining
The first and most popular in 2022 MEV BOOST Reley - FlashBots was the first to adhere to OFAC sanctions and AML lists. Because of this, already in the fall of 2022, 80% of all validators complied with AML and OFAC requirements without knowing it.
The problem became so obvious that the creators of Ethereum began to discuss this problem at all conferences and urge the crypto community not to use MEV BOOST services and liquid staking services that support OFAC sanctions.
And the crypto community heeded this call, creating many other MEV BOOST services, and validator owners began switching from Flashbots to alternative solutions that do not support AML and OFAC lists. Thanks to this, sanctions support is now provided by 30% to 40% of all validators, which is also quite a lot, but not as critical as it was at the end of 2022.
The list of Mev Boost Releys can be found at this link
It is convenient to monitor the number of validators that support AML and OFAC on the mevwatch.info service
