This paper examines the legal ramifications of Miner / Maximal Extractable Value (MEV), a phenomenon in which some entities (e.g., miners or validators) leverage their positional advantages to generate extra profits on blockchains. In previous work, Barczentewicz et al. argued that some MEV extraction techniques could constitute illegal market manipulation under United States securities law, depending on the publicness of the victim transactions. While their analysis applies to typical Ethereum and Flashbots implementations, we contend that the rapidly evolving blockchain ecosystem and the emergence of new MEV mitigation measures necessitate a revised test for market-manipulation liability. Our proposal focuses on the principle of respecting the initiating user’s intent, rather than simply the network status of the transactions. We also identify new enforcement challenges that arise from the decentralization nature of blockchains. By offering a nuanced understanding of the MEV landscape and exploring the legal implications for manipulation liability, this paper contributes to the ongoing discussion on MEV regulation in blockchain ecosystems.