Please be advised that this Friday, December 15, 2006, we are implementing a new system for creating the daily CBOT-CME SPAN files.  We have worked extensively with the service bureaus to verify that the switch will be transparent to firms, but wish to call your attention to the fact of the switch and to several insignificant differences:

• For combined commodities without intracommodity spread charges, the new files provide the "intracommodity spread charge method" value on the type "3" record as "01", meaning no charge, rather than as method "10", the table-driven method.  Both methods produce an equivalent zero value for intracommodity spread charge.
• The new files will always contain combined commodity-level data for active products, even if contracts are not yet eligible to trade or are currently not eligible.  We think firms will find this convenient.
• Within blocks of records, for example the type "8" records, data is sorted in ascii rather than ebcdic.

The new files have been produced in production parallel with the existing ones for several months, and, like the existing ones, are produced five times daily.  If you wish to test with the new files, they are available at ftp.cme.com/pub/span/data/ccl/test.

Beginning this Friday December 15, 2006 with the a.m. SPAN file, the files in the main directory at ftp.cme.com/pub/span/data/ccl will be the new ones.  The old ones will temporarily be available in the "test" directory at ftp.cme.com/pub/span/data/ccl/test.  On the Firm FTP Server, on the morning of the 15th, the files in the pub/span directory will be the new ones.

If you have any questions or concerns, please contact CME Clearing's Risk Department at 312-648-3888 or CME Clearing's main number at 312-207-2525.