CORPORATE EVENT: Alexion Pharmaceuticals, Inc. 2 for 1 Stock Split.

Clearing House Advisory Notices

To	Clearing Member Firms
From	CME Clearing
Subject	CORPORATE EVENT: Alexion Pharmaceuticals, Inc. 2 for 1 Stock Split.
Notice Date	2008-08-22
Notice Number	08-194
Effective Date	2008-08-25
Alexion Pharmaceuticals, Inc. (“ALXN") has announced a 2 for 1 stock split. The Ex-distribution Date is Monday, August 25, 2008. The Payable Date is August 22, 2008. The Record Date is August 12, 2008. This corporate action will be coordinated with the Options Clearing Corporation. If you have any questions regarding the information provided in the document, please call CME Clearing risk management hotline at (312) 648-3888. For the full-text of this advisory, please click here.