Notice No. 586
November 14, 2008

Performance Bond Requirement Changes -- Margins for CY, BB and BZ

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As per the normal review of market volatility to ensure adequate collateral coverage, the Chicago Mercantile Exchange Inc., Clearing House Risk Management staff approved the performance bond requirements for the following products listed below. The rates are effective at the close of business on Monday, November 17th, 2008.

NEW TIER STRUCTURE AND MARGIN RATE CHANGES FOR THE CLEARPORT BRENT CLENDAR SWAP FUTURES (CY), BRENT BULLET SWAP FUTURES (BB) AND BRENT CRUDE OIL-LAST DAY FUTURES (BZ)

Note: The revised margins are in bold

NYMEX Division Outright (Scan) Margins on CY, BB and BZ

	Clearing Member / Maintenance Margin		Member Customer Initial Margin		Non-Member Customer Initial Margin
	*New*	Old	*New*	Old	*New*	Old
CY	$8,500	$9,500	$9,350	$10,450	$11,475	$12,825
BB	$8,500	$9,500	$9,350	$10,450	$11,475	$12,825
BZ	$8,500	$9,500	$9,350	$10,450	$11,475	$12,825

Should you have any questions or require any further information, please contact ExchangeInformation@cmegroup.com