Mantle

Mantle Staked Ether (mETH) is a non-rebasing liquid staking token that is the staking backbone of the Mantle ecosystem, accruing ETH staking rewards.

Backed by the Mantle treasury and tightly integrated with the Mantle L2 ecosystem and its DeFi venues.

- mETH (Mantle Staked Ether): A value-accumulating (reward-bearing) ETH liquid staking receipt token issued by mETH Protocol on Ethereum L1. Balance stays fixed while its ETH exchange rate rises with consensus- and execution-layer staking rewards. Permissionless and non-custodial. - cmETH (Mantle Restaked Ether): A composable liquid restaking token minted 1:1 when users deposit mETH via the Teller contract. Represents a portfolio of underlying restaking positions across EigenLayer, Symbiotic and Karak plus their AVSs, earning restaking rewards on top of base staking yield. - COOK: Governance token of mETH Protocol (genesis supply 5 billion). Holders vote on protocol direction including staking parameters, reward structures and strategic initiatives. TGE around late October 2024. - BoringVault / PositionManagers: cmETH principal mETH is custodied in BoringVault and can move only to approved addresses/positions. PositionManagers are simple, non-upgradable contracts controlled by BoringVault that constrain permitted calls and integrate third-party restaking protocols; StrategistNodes rebalance the portfolio verified against a MerkleRoot.

- Smart Contract: mETH, cmETH, BoringVault, PositionManagers and oracle are on-chain contracts. Audits across releases surfaced HIGH/MEDIUM/LOW findings (e.g. the MixBytes review reported 3 HIGH, 4 MEDIUM, 7 LOW, all acknowledged or fixed); residual bug/exploit risk remains. - Reserve / Depeg: mETH is a reward-bearing claim on staked ETH whose secondary-market price can trade below its intrinsic ETH exchange rate during stress or thin liquidity; cmETH adds a second wrapping layer that can decouple from mETH. - Counterparty: cmETH routes principal into third-party restaking protocols (EigenLayer, Symbiotic, Karak) and their AVSs, exposing holders to those external protocols' operator, slashing and contract failures beyond Mantle's control. - Network: Underlying yield depends on Ethereum PoS validator performance; validator downtime or slashing reduces mETH's exchange rate, and unstaking is subject to Ethereum's exit queue plus protocol withdrawal delays. - Governance: mETH Protocol is governed by Mantle with COOK as its governance token and a large treasury/contributor allocation; concentrated voting power and treasury control could steer parameters against some stakeholders. - Oracle: The mETH exchange rate relies on an oracle (separately audited); faulty or manipulated oracle updates could misprice mETH for mint/redeem and downstream DeFi integrations.

- Repo / cash-management sweep on a Treasury position: similar — Like sweeping idle cash into an interest-bearing, redeemable instrument, staking ETH into mETH turns idle ETH into a yield-accruing, transferable claim whose value grows over time.; differs — mETH yield comes from Ethereum PoS validation (variable, subject to slashing) rather than a contractual money-market rate; redemption is subject to on-chain unstake queues and smart-contract risk rather than a regulated custodian.