1.   As the margin account falls below a particular threshold, it has to be topped up with additional payments known as variation margin.

2.   In the case where the long elects for cash settlement, he simply receives the sum of money in his margin account as final settlement.

3.   And as stocks have rallied, the value of holdings in margin accounts has risen in lockstep.

4.   Are there any risks I should be aware of in margin accounts?

5.   Because investors must repay the money within five months, the margin accounts create short-term selling pressure.

6.   Brokerages make money on the loan, and they typically require customers who hold margin accounts to give the firm the right to lend shares held in those accounts.

7.   Employees with options also benefited until the stock began to fall and the consequences of the margin accounts became apparent.

8.   Instead, the brokers called the loans a credit line rather than a margin account, the former customers said.

9.   Many analysts also expect the government to ease regulations on margin accounts to allow brokerages to increase the amount of loans they can extend to investors.

10.   Margin accounts are set up for investors who borrow from a brokerage firm and pledge cash or securities as collateral.