• The basic margin requirement for security futures is 20% of the underlying value of the contract (initial and maintenance margin).
• This 20% minimum may be reduced for certain types of futures market positions, such as calendar and basket spreads, and for certain offsetting positions in stock options and cash securities, provided the security futures are held in securities accounts.
• Margin requirements can be satisfied with cash, margin securities, and open trade equity in other futures accounts.
• Certain industry professionals (such as qualified market makers) are exempt from these requirements.
• Portfolio-based margining (e.g. SPAN margining) is not yet permitted for customer positions in security futures. Firms will nonetheless continue to receive SPAN files that reflect the appropriate minimum margin requirements.

The margin requirements applicable to a particular investor's account may vary. For example, a brokerage firm may choose to require higher margin deposits than the minimums permitted under the rules. Investors, therefore, are encouraged to discuss the margin requirements for their accounts directly with their broker.

Click here to view the final SEC/CFTC rules in PDF format.