Morpho blue
Morpho blue liquidations use LLTV and oracle-priced collateral to determine when a liquidator can repay debt
Morpho blue liquidations become possible when a position's borrowed amount exceeds its oracle-priced collateral value multiplied by the market's liquidation loan-to-value threshold (LLTV). A borrower can move away from that boundary by repaying debt or adding the market's collateral asset before another transaction liquidates the position. Once liquidation executes, debt and collateral both change, so the next step must use the updated onchain position rather than an earlier interface preview.
In short: Repaying debt or adding collateral before a liquidation confirms can restore health or increase the position's margin.
Market isolation contains losses, while health checks enforce LLTV
Isolation keeps each market's loan asset, collateral asset, oracle, interest rate model, and LLTV inside its own accounting boundary.
Isolation contains market losses
A liquidation in one market changes positions and balances in that market. It doesn't draw collateral from another market or automatically spread bad debt to unrelated suppliers. The boundary has limits, however. Two markets may still depend on the same token or oracle design, so a shared failure can affect them separately at the same time.
Health checks enforce the selected threshold
Before a borrow or collateral withdrawal succeeds, the contract checks whether the resulting position remains healthy. The position becomes eligible for liquidation when accrued debt exceeds the LLTV-adjusted collateral value. This protection relies on the oracle output and the debt calculated during execution. It can't reserve time for the borrower or make a pending correction count as confirmed state.
Those safeguards contain accounting effects, but they don't remove transaction-ordering or oracle risk near the boundary.
Read the liquidation boundary from live state
The maximum supported debt equals the collateral amount multiplied by the oracle price and LLTV. Health factor expresses the same relationship as maximum supported debt divided by borrowed assets. A value above one has room before liquidation, while a value below one means the contract's health condition has failed. At the exact boundary, contract arithmetic and rounding matter, so a rounded display of 1.00 isn't enough evidence.
Debt must be read after interest accrual because borrow shares convert into an asset amount which grows over time. Collateral value can move when the market's oracle output changes. A useful check therefore combines the market ID, position owner, collateral balance, borrow shares, accrued market totals, oracle price, and fixed LLTV at one observation point.
Which action creates more distance from LLTV?
First check which asset is available: repayment needs the market's loan asset, while adding collateral needs its designated collateral asset. Either action can improve health, but the better option depends on the confirmed amount it changes. Repayment reduces the denominator of the health-factor calculation. Additional collateral raises its numerator after the oracle converts that collateral into the loan asset's unit of account.
Repayment reduces debt
If the position has collateral amount C, oracle price P, LLTV L, and debt D, repaying an amount R changes health factor to C × P × L divided by (D - R). The repayment must target the correct market and position owner. An approval, signature, or pending transaction doesn't reduce D until the repayment itself confirms.
Additional collateral raises supported debt
Adding collateral amount A changes the numerator to (C + A) × P × L. This route depends on having the correct collateral asset available and getting the transaction confirmed before liquidation changes the position. It also leaves the original debt and its interest accrual in place, so the restored margin may shrink again.
Comparing both formulas with the same current state shows which available action creates the larger verified margin.
Four stages from early signal to confirmed outcome
Assume a position begins healthy with debt D, oracle-priced collateral value C, and threshold L. It remains healthy while D is no greater than C × L. A collateral decline reduces C, while accrued interest increases D. The response remains under the borrower's control only until a liquidator's transaction changes the position first.
| Stage | Boundary and observable state |
|---|---|
| Starting record | D is no greater than C × L; record the market and owner with that state. |
| Adverse change | C falls or D rises; recalculate after interest accrual and the current oracle reading. |
| Selected response | Repay debt or add collateral; a pending transaction hasn't changed the threshold test. |
| Exit condition | Confirm the updated position; if liquidation landed first, use its remaining debt and collateral. |
If the asset needed for the chosen action is unavailable, don't submit it. Re-read the onchain position before choosing another route, because a separate transaction may already have updated it.
Can an oracle recovery prevent liquidation?
Yes, if the contract sees a healthy position when the liquidation transaction executes. The liquidation call accrues interest, reads the market's oracle, and checks health against LLTV. If the refreshed state satisfies the health condition, the call can't proceed. A price shown elsewhere doesn't control this check because the selected market uses its configured oracle output.
If liquidation confirms before the market's oracle reflects the recovery or a borrower correction takes effect, the later change doesn't reverse the collateral seizure. If the oracle reflects the recovery first and the refreshed position is healthy, the liquidation call reverts. The position remains unchanged except for separate updates already confirmed.
Debt, collateral, and losses settle in separate records
A confirmed liquidation updates the borrower's position rather than closing every unhealthy loan in the same way. The size chosen by the liquidator determines how much debt is repaid and how much collateral is seized.
A successful liquidation reduces both the borrower's debt and the collateral recorded in that market.
Residual positions need a fresh health check
After a partial liquidation, remaining debt and collateral form a new ratio. The new ratio may be healthy, or the position may remain liquidatable after the update. Reading only the debt reduction misses the collateral transferred to the liquidator. Recalculate from the updated borrow shares, collateral balance, accrued totals, and oracle output.
A partial liquidation isn't proof the position has returned above the threshold.
Exhausted collateral can expose bad debt
If all available collateral is seized and debt remains, the unrecovered amount becomes bad debt in that isolated market. Its accounting loss is borne by that market's suppliers rather than suppliers in every Morpho blue market. This is the limit of liquidation as a lender safeguard: collateral can't repay value it no longer covers.
For the borrower, the position records no collateral and no remaining debt after the bad debt is realized. For suppliers, the market's total supply assets fall by the realized loss.
LLTV links the trigger to seizure economics
LLTV sets both the health boundary and an input to the liquidation incentive factor (LIF). In the Morpho blue core formula, LIF is the lower of 1.15 and 1 divided by (1 - 0.3 × (1 - LLTV)). The factor converts repaid debt into a larger oracle-valued collateral amount for the liquidator. Lower LLTV settings therefore produce a larger incentive under this formula, up to its cap.
The core liquidation call can repay part or all of a borrower's debt, provided the corresponding collateral calculation can be satisfied. A full repayment can close the debt when collateral supports the seizure. A partial repayment leaves a residual position which must be tested again. Liquidators also compare the incentive with execution, funding, and asset-conversion costs, so eligibility doesn't ensure an immediate transaction.
Choose the next action from the updated position
A healthy residual position can become liquidatable again as interest accrues or the oracle price moves. Remaining debt can be repaid before collateral is withdrawn. If collateral has already been seized, adding funds later affects only the position which remains; it doesn't recover the completed transfer. Record the market, owner, debt, collateral, and health calculation before choosing the next transaction.
Useful questions about Morpho blue liquidations
Does the borrower receive a grace period after the LLTV boundary is exceeded?
No protocol-level grace period delays eligibility once debt exceeds the oracle-priced collateral value multiplied by LLTV. An external account can submit a liquidation immediately. Whether it executes depends on the position state and transaction ordering when the contract processes the call, not on how long an interface has displayed a warning.
Can a pending repayment prevent another account from liquidating first?
No, a pending repayment hasn't changed the onchain debt. If a liquidation is processed first while the position is unhealthy, it can alter the debt and collateral before the repayment executes. The later transaction may then produce a different result or revert because its assumptions no longer match the updated position.
Why can an interface show a different health factor from the liquidation check?
The interface may use an earlier block, estimated accrued interest, a rounded display, or an oracle reading captured at another moment. The contract makes its decision from the market state available during execution and applies its own integer rounding. Compare values from the same market, owner, and observation point before treating a displayed health factor as current.
Can supplying the loan asset reduce a borrower's debt automatically?
No, supplying the loan asset creates or increases a lender position in the selected market. It doesn't repay the borrower's debt unless a separate repayment operation uses those assets for that position. Confirm the borrow shares or current debt amount decreased; a new supply balance alone isn't evidence the liquidation margin improved.
When can remaining collateral be withdrawn after a full repayment?
Remaining collateral can be withdrawn after the debt repayment confirms and the position records no outstanding borrow. Repayment and collateral withdrawal are separate state changes, even when an interface prepares them together. Check the final position owner and market before withdrawing, especially if a liquidation or another repayment was processed during the same period.
Which costs determine whether a liquidator acts on an eligible position?
A liquidator compares the LLTV-based collateral incentive with transaction execution, funding, asset-conversion, and slippage costs. Eligibility only permits the call; it doesn't prove the transaction is profitable or will arrive before another liquidator. A small available incentive or difficult conversion path can leave an unhealthy position unresolved for longer.
Can a third party repay debt without triggering liquidation?
Yes, another account can repay debt on behalf of a borrower without using the liquidation path. That repayment reduces the selected position's debt but doesn't give the payer the borrower's collateral or a liquidation incentive. The payer must use the market's loan asset and identify the intended market and borrower correctly.
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