Date:                           October 30, 2007

Recipients:                 Members and Independent Software Vendors

Authorized by:            Jeffrey S. Hersh

Title:                           Central Standard Time (CST)

Action Date:               November 4, 2007 (trade date November 5)

Recommended for:    All Departments

Related Bulletins:      Bulletin #16/2007

Attachment:                N/A

SUMMARY:

Central Standard Time begins in Chicago at 2:00 a.m. on Sunday, November 4, 2007.  In accordance with Rule 1007.00 – Hours for Trading, the Exchange will conform to Chicago time. 

All trading schedules will be on Central Standard Time beginning with the overnight electronic session on Sunday, November 4, 2007.

The e-cbot API does not require any changes.  In addition, the CBOT-provided hardware at your site will not require any changes.  However, Trading Applications and related user support applications that are time-dependent may be affected by this CST change.  Please be certain to consult with your Independent Software Vendor (ISV) or your internal application development team to ensure that the CST change will be addressed before November 4, 2007.

Please ensure that your systems will be available and operating for the opening of trading Sunday, November 4, 2007 at 6:00 p.m. Chicago time. 

If you have any questions about this Bulletin, please contact Market Operations at 312-347-4600 or your Key Account Manager.