USFE uses The Clearing Corporation, which has set the market standard for clearing U.S. Treasury derivative products, to provide its clearing services. For more information, please visit www.clearingcorp.com. Margin Rates The following initial and maintenance margin levels are in effect for USFE. Members must collect margin from their customers in accordance with USFE Rule 506. For margin rates on USFE products, please visit The Clearing Corporation’s website here. Daily Span For access to the SPAN array files for USFE, please click on the link below: http://www.clearingcorp.com/Span/index.cgi