Mantle Staked Ether

Mantle Staked Ether (METH, commonly styled as mETH) is a non-custodial liquid staking receipt token launched in December 2023. Deployed on the Ethereum mainnet and integrated across the Mantle Layer 2 network, the token represents staked ETH. It operates under a mint-and-burn mechanism where METH is minted when users deposit ETH and burned upon redemption. Rather than rebasing, METH functions as a value-accruing receipt token whose exchange rate relative to ETH increases as staking rewards—derived from execution layer priority fees, consensus rewards, and MEV—accumulate within the protocol.

The underlying mETH Protocol was developed within the Mantle ecosystem and supported by Mantle Treasury incentive initiatives, reaching a peak total value locked of approximately $2.19 billion. Protocol governance was initially coordinated via Mantle DAO and expanded in October 2024 with the introduction of the dedicated COOK governance token. The protocol's codebase has been audited by multiple independent security firms, including MixBytes, Hexens, Secure3, and Verilog, and the protocol maintains an active bug bounty program on Immunefi.

In February 2025, the protocol was involved in a security incident when 15,000 cmETH (a restaking receipt token in the mETH Protocol product line, valued at roughly $43 million) was compromised during the Bybit exploit attributed to the Lazarus Group. The protocol utilized its built-in eight-hour withdrawal delay and emergency pause mechanisms to fully recover the compromised assets within hours, resulting in zero net financial loss. Other risks highlighted in protocol evaluations include concentrated token holder distribution, thin secondary market trading liquidity, and administrative reliance on a 6-of-12 Mantle Security Council multisig for contract upgrades.