A Margin Call is a demand, usually resulting from the price decline of a security bought on margin, that a customer deposit enough money or securities to bring a margin account up to the initial margin or minimum maintenance requirements. If a customer fails to respond, securities in the account may be liquidated.
Mark to Market (MTM) is a financial accounting method where the value of an asset is adjusted to reflect its current market value rather than its book value. It's used in margin accounts to ensure compliance and by mutual funds to report daily net asset values.
