# Force Close
Passive liquidation is a crucial mechanism in futures trading aimed at maintaining market stability and safeguarding traders from significant losses. In SubstanceX, there are two mechanisms that trigger passive liquidation of a user's position:
### Liquidation
When a user's net position value falls below the minimum maintenance margin, liquidation is triggered.
1. Net value = Collateral + PNL after fees.
2. Minimum maintenance margin = Size \* Mark Price \* MaintenanceMarginRatio + Est. Liq. fees.
3. For Long: Est. Liq. price = (Collateral + Fees - Entry price \* Size) / (Size \* (MaintenanceMarginRatio + Est.LiquidateFeeRatio - 1)\
For Short: Est. Liq. price = (Collateral + Fees + Entry price \* Size) / (Size \* (MaintenanceMarginRatio + Est.LiquidateFeeRatio + 1)
* Typically, the Est.LiquidateFeeRatio for each pair is equal to its TradingFee.
* Liquidation will only result in the user losing all the collateral associated with that position. The balance in the user's Exchange Wallet will not be affected.
\
**Case Study:**
| Pairs | BTC/USD |
|---|
| Long / Short | Long |
| Collateral （$） | 10,000.00 |
| Entry Price（$） | 30,000.00 |
| Leverage | 30.00 x |
| Size | 10.00 |
| Mark Price（$） | 31,000.00 |
| Fees（$） | -200.00 |
| MaintenanceMarginRatio | 0.5% |
| TradingFeeRate | 0.08% |
| Est. Liq. Price（$） | 29,165.95 |
### MaxProfit Liquidation
When a user's PNL on a position reaches ten times the collateral, a maxprofit liquidation is triggered, and the system will close the perpetual position at market price.
1. Max Profit = Collateral \* MaxProfitRatio
2. For Long : Max Profit Price = Entry Price + Max Profit / Size
3. For Short : Max Profit Price = Entry Price - Max Profit / Size
* Please note that max profit does not represent actual earnings. Actual earnings need to account for pending fees.
* The MaxProfitRatio may vary for different trading pairs. You can find specific details in [perpetual-specifications](https://docs.substancex.io/perpetual/perpetual-specifications "mention").
**Case Study：**
| Perps | BTC/USD |
| ------------------- | ---------: |
| Collateral （$） | 10,000.00 |
| Entry Price（$） | 30,000.00 |
| Leverage | 30.00 x |
| Size | 10.00 |
| MaxProfitRatio | 10 |
| Max Profit（$） | 100,000.00 |
| Max Profit Price（$） | 40,000.00 |
| Close Price（$） | 40,000.00 |
| Fees（$） | -100.00 |
| PnL（$） | 99,900.00 |