Is a Margin Call an Indication That the Trader Has Realized a Loss?

Yes, a margin call is a direct indication that the trader has incurred a realized loss that has reduced their account equity below the maintenance margin level. The MTM process daily converts paper (unrealized) losses into realized cash losses (variation margin outflow), and the margin call is the demand to replenish the account after those realized losses have been deducted.

Can an Unrealized Loss Trigger a Margin Call?
What Is the “Margin Call” Process and How Does It Relate to Maintenance Margin?
How Does a Margin Call Work in a Leveraged Futures Position?
What Is the Trigger for a Maintenance Margin Call?
What Is the Difference between ‘Maintenance Margin’ and ‘Variation Margin’?
What Is the Practical Difference between a Maintenance Margin Call and a Variation Margin Call?
What Is the Difference between a Variation Margin and a Maintenance Margin?
What Is Maintenance Margin and What Happens If an Account Falls below It?

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