Technical Specifications

Wrapped M Specification

Low-level technical specification for Wrapped M (wM) - function signatures, events, errors, and storage layout.

Contract overview

WrappedMToken (wM) is a non-rebasing ERC-20 wrapper for the rebasing $M token. It maintains yield-earning capabilities while providing compatibility with DeFi protocols that require standard ERC-20 tokens.

Decimals: 6 (matches $M)
Index: Derived from the underlying $M token's index
Yield realization: Explicit claiming (not automatic rebasing)

Key functions

Wrapping and Unwrapping

Function	Description
`wrap(address recipient, uint256 amount)`	Deposit `$M` tokens, receive equivalent wM
`unwrap(address recipient, uint256 amount)`	Burn wM tokens, receive equivalent `$M`
`wrapWithPermit(address recipient, uint256 amount, uint256 deadline, uint8 v, bytes32 r, bytes32 s)`	Wrap with gasless `$M` approval

ERC20 Standard

Function	Description
`transfer(address to, uint256 amount)`	Transfer wM tokens
`transferFrom(address from, address to, uint256 amount)`	Transfer wM on behalf of another address
`approve(address spender, uint256 amount)`	Approve a spender allowance
`balanceOf(address account)`	Returns stored balance (excludes unclaimed yield)
`totalSupply()`	Returns total wM in circulation

Earning Management

Function	Description
`startEarningFor(address account)`	Activate earning mode for an approved account
`stopEarningFor(address account)`	Deactivate earning mode (claims outstanding yield)
`enableEarning()`	Enable earning for the wM contract itself on `$M`
`disableEarning()`	Disable earning for the wM contract on `$M`

Yield Management

Function	Description
`claimFor(address account)`	Claim accrued yield for an account
`setClaimRecipient(address recipient)`	Set a custom address to receive claimed yield

Balance and Yield Queries

Function	Returns
`balanceOf(address account)`	Stored balance (excludes unclaimed yield)
`accruedYieldOf(address account)`	Unclaimed yield for an earning account
`balanceWithYieldOf(address account)`	`balanceOf` + `accruedYieldOf`
`isEarning(address account)`	Whether the account is in earning mode
`totalNonEarningSupply()`	Sum of all non-earning balances
`totalEarningSupply()`	Sum of all earning balances (excluding yield)
`projectedEarningSupply()`	Total earning supply if all yield were claimed
`excess()`	`$M` held by contract minus total wM liabilities

Excess Management

Function	Description
`claimExcess()`	Transfer accumulated excess `$M` to `excessDestination`
`excessDestination()`	Returns the address that receives claimed excess (typically Distribution Vault)

Admin Operations (via EarnerManager)

Function	Description
`setEarnerDetails(address account, bool status, uint16 feeRate)`	Set earning status and fee rate for an account
`setEarnerDetails(address[] accounts, bool[] statuses, uint16[] feeRates)`	Bulk set earning details
`earnerStatusFor(address account)`	Check earner status for an account
`getEarnerDetails(address account)`	Get full earner details including admin and fee rate

Account storage model

struct Account {
    bool isEarning;           // Whether the account is in earning mode
    uint240 balance;          // Current token balance (excluding yield)
    uint112 earningPrincipal; // Principal amount for earning accounts
    bool hasClaimRecipient;   // Whether a custom recipient is set
    bool hasEarnerDetails;    // Whether admin fee settings exist
}

Events

Event	Description
`Transfer(address indexed from, address indexed to, uint256 value)`	Standard ERC20 transfer
`Approval(address indexed owner, address indexed spender, uint256 value)`	Standard ERC20 approval
`StartedEarning(address indexed account)`	Account entered earning mode
`StoppedEarning(address indexed account)`	Account exited earning mode
`Claimed(address indexed account, address indexed recipient, uint256 yield)`	Yield claimed
`ExcessClaimed(uint240 amount)`	Excess `$M` claimed to destination

Errors

Error	Condition
`NotApprovedEarner()`	Account is not approved for earning
`EarningIsEnabled()`	Operation not permitted while earning is enabled
`EarningIsDisabled()`	Operation requires earning to be enabled
`InsufficientBalance(address account, uint256 balance, uint256 amount)`	Transfer, unwrap, or burn exceeds balance

Index mechanism

The wM index is derived from the underlying $M token's index:

When earning is enabled:

wM_{\text{index}} = \frac{M_{\text{currentIndex}}}{enableMIndex} \times disableIndex

When earning is disabled:

wM_{\text{index}} = disableIndex

Yield claim recipient priority

When determining where to send claimed yield:

User-specified recipient (via setClaimRecipient)
Governance-specified override (via Registrar)
The account itself (default)

Solvency invariant

\text{M Balance}_{(\text{wM contract})} \ge \text{totalNonEarningSupply} + \text{projectedEarningSupply}

The excess above this threshold accumulates from yield on $M backing non-earning wM holders and minor rounding effects.

Wrapped M overview - Full conceptual documentation
M Token specification - $M token spec
Distribution Vault - Where excess is typically directed

Wrapped M (wM)

Complete documentation of Wrapped M (wM), the non-rebasing ERC-20 wrapper that maintains yield-earning capabilities while providing DeFi compatibility.

Deployments

Contract addresses for M0, TTG, and Wrapped M across all supported chains.