An investment in financial assets that is partly financed by borrowed money. A margin account with a broker allows for limited borrowing to purchase assets. The initial margin requirement is the minimum proportion of the investment that has to be provided from the investor’s own funds. A margin account is marked to market at the end of each trading day to determine the actual margin. If the actual margin falls below the maintenance margin requirement the investor is obliged to add cash or securities to the margin account. Trading on the margin raises the return on a successful investment compared to a straight cash purchase but also magnifies losses. This increases the risk of the investment.