Cross Margining
Cross margining is a risk management feature that allows a trader to use the collateral from one position to offset the margin requirements of another. This system is highly capital efficient because it prevents the need for excess collateral to be locked up in individual isolated accounts.
If one position makes a profit, that gain can be used to cover the margin requirements of a losing position, reducing the likelihood of liquidation. However, it also means that a loss in one area can deplete the collateral for the entire account, potentially leading to cascading liquidations.
It is a common feature in advanced derivatives exchanges, designed to improve liquidity and trading flexibility. Users must understand the implications of shared collateral pools.