Crypto community votes to eliminate MEV issues from BNB chain

On Feb. 7, Binance founder Changpeng Zhao posted a poll on X asking if BNB Chain should eliminate/aggressively reduce Maximal Extractable Value (MEV) issues.
It is reported that MEV issues have cost BNB Chain users over $1 billion in the 2020s. As expected, over 80% of users voted in favor of eliminating MEV issues.

Table of Contents

What is MEV?
Why not eliminate MEV issues?
What are the possible solutions?
What is MEV?
Maximal Extractable Value refers to the maximum amount of fees a validator can extract from network transactions by rearranging the order of transactions waiting to be included in a block.
Validators can manipulate market prices by changing the sequence of orders, making MEV similar to an “invisible tax.”
The issue was first brought up in 2014 when an anonymous Reddit user expressed concerns about potential front-running by miners in the Ethereum network. Even before the rise of DeFi, this commentator clearly anticipated the possible abuse of the system:

For example, in an Ethereum decentralized stock exchange, I could run multiple miners to process exchange transactions. When a large buy order comes in, I could delay it on all my miners, place a buy order myself on all my miners simultaneously, and then process the original transaction. I would get the best price and could potentially sell to the originator for an immediate profit.
Although MEV is commonly associated with the Ethereum network, BNB Chain users have also experienced significant problems with it. Their votes demonstrate their dissatisfaction.
Various manipulations occur on Automated Market Making platforms through bots. One particularly damaging MEV attack is known as the “sandwich attack,” where a target order is placed between two orders of a malicious actor to manipulate the price and close the position at a more favorable price.
In 2021, BNB Chain users allegedly lost around $300 million in sandwich attacks. However, the highest reported harm occurred in 2024 when a single bot carried out approximately $40 million worth of sandwich attacks within three months, resulting in a total cost of $1.5 billion from sandwich attacks.
The affected blocks accounted for 35.5% of the total.
Why not eliminate MEV issues?
Should the BNB dev team introduce solutions to limit MEV attackers, or should things remain as they are? There is no definitive answer to this question. The concerns about MEV attacks are easy to understand. These attacks are considered unethical as bad actors exploit vulnerabilities in the network to profit from people exchanging cryptocurrencies.
Bots act quickly, and a well-organized automated trading system can take advantage of MEV opportunities at a speed impossible for a human. Unsuspecting traders end up paying for the profits made by those who exploit them through automated trading.
Front running is a legal issue, and front running in the crypto space remains a gray area. It is not explicitly prohibited as this vulnerability is seen as inherent to decentralized platforms. However, given the scale of the damage, many have praised efforts to reduce MEV attack opportunities through technical advancements, as indicated by Zhao’s poll.
But why do many respondents prefer to keep the MEV issues as they are? Firstly, many believe that MEV opportunities are an integral part of decentralized finance and cannot be eliminated. Others find MEV acceptable because, while it is an exploit, it is not a violation. As long as MEV is simply an opportunity to earn extra profits, they see no reason to oppose it.
Finally, some argue that the opportunity for MEV attacks incentivizes more validators, which in turn increases decentralization and makes the network safer for everyone.
In general, the “MEV issues” are seen as the price users pay for utilizing decentralized finance platforms.
This viewpoint disregards the similarities between an MEV trick like the time bandit attack and the infamous 51% attack, which are contrary to the principles of decentralization and safety for all.
What are the possible solutions?
Zhao himself acknowledges that MEV-related problems cannot be completely eliminated, but there are ways to reduce the harm.
One of the tools to combat MEV attacks is the use of remote procedure calls (RPCs). RPCs direct transactions to a private mempool, making it more difficult for bad actors to execute sandwich attacks.
Another solution that has been in development since 2023 is the Proposer-Builder-Separation (PBS) model. This model outsources block proposals to separate actors who prepare blocks for validators to choose the most lucrative options without being able to exploit them. Increasing the number of relays in the BNB Chain may also be a way to limit the impact of MEV attacks.
Considering the existence of ongoing projects to address the issue and the significant financial losses caused by MEV attacks, it is not surprising that there is strong support for reducing MEV.