Margin Call

In finance, a margin is collateral that the holder of a financial instrument has to deposit to cover some or all of the credit risk of their counterparty (most often their broker or an exchange). This risk can arise if the holder has done any of the following:

The collateral can be in the form of cash or securities, and it is deposited in a margin account. On United States futures exchanges, "margin" was formerly called performance bond. Most of the exchanges today use SPAN (Standard Portfolio Analysis of Risk) methodology for calculation of margin in 'Options' and 'Futures'. SPAN was developed by the Chicago Mercantile Exchange in 1988.

Margin buying

Jane buys a share in a company for $100, using $20 of her own money, and $80 borrowed from her broker.