The Exchange uses Mark Price as a means to help avoid unnecessary liquidations and to manage user position risk. Moreover, Forced Liquidation will be a progressive liquidation and not a full liquidation of the position; however, there may be cases where the position will be liquidated in full for traders who hold relatively small positions.
Margin Balance is calculated as follows
Margin Balance = Deposits - Withdrawals + Realized PnL - Fees
What happens if the Margin Balance falls below the Initial Margin?
If the Margin Balance is lower than the Initial Margin, then
All open Orders that would increase the position will be automatically cancelled, and new orders that would increase the position will be rejected
Only Orders that would decrease the position will be allowed (e.g. you can only place sell Orders if you hold a long position)
An email will be sent as a warning to monitor your position closely, to add more Collateral, or to close your position
What happens if the Margin Balance falls below the Maintenance Margin?
If the Margin Balance is lower than the Maintenance Margin, then
All open Orders will be automatically cancelled, and all new Orders will be rejected
Withdrawals will be suspended during this time
The position will be progressively liquidated so that the Margin Balance is greater than the Initial Margin and Maintenance Margin
An email will be sent as a confirmation that the position has been progressively liquidated
All liquidation Orders will be subject to a liquidation fee contributing to the Insurance Fund. Liquidation fees can be found here.