The margin requirement for accounts holding concentrated positions in low cap stocks is as follows:

• An alternative stress test will be considered following the margin calculation currently in place. Here, each stock and its derivatives will be subject to a stress test which simulates a price change reflective of a $500 million decrease in capitalization (e.g., 25% in the case of a stock with a market capitalization of $2 billion; 30% for a stock with a market capitalization of $1.5 billion; etc.). Stocks with a market capitalization of $500 million or below will be subject to a stress test as if the price has fallen to $0.
• For the stock which projects the greatest loss assuming a $500 million decrease in capitalization, that loss will be compared to the initial margin as determined under the preceding calculation for the aggregate portfolio and, if greater, will become the initial margin requirement.
• If the initial margin requirement is increased, the maintenance margin for that same stock and its derivatives will increase to approximately 90% of the initial requirement for the aggregate portfolio.