May 4, 2005

Exhibit 10.24

Xxxxxxx X. Xxxxx

Chairman of the Board

                                         May 4, 2005

Xx. Xxxxxxx X. Xxx

Chicago Board of Trade

000 X. Xxxxxxx Xxxx

Suite 600-A

Chicago, Illinois 60604

RE: Employment Agreement dated September 1, 2003 between CBOT and Xxxxxxx Xxx – Extension Notice

Dear Mr. Xxx:

Pursuant to paragraph 4(a) of the Employment Agreement dated September 1, 2003 between the Board of Trade of the City of Chicago, Inc (CBOT) and Xxxxxxx Xxx, please consider this as notice from the CBOT to extend the term of the Agreement from December 31, 2006 to and including December 31, 2008. As provided in paragraph 4(a), your Base Salary for each of the two additional years (i.e., 2007 and 2008) shall be $1,200,000.00 per year and the your minimum Performance Bonus for each of the two additional years shall be $500,000.00 per year. This extension is made with the parties’ understanding that, subject to their subsequent agreement, the minimum guaranty aspect of the Bonus may be replaced or modified by a long term incentive compensation component to the Employment Agreement.

Please indicate your acceptance of this two year extension by affixing your signature on the line provided below. After you have signed this notice, kindly return it to me. I have enclosed a duplicate original for your records.

BOARD OF TRADE OF THE CITY OF CHICAGO, INC.

By:		/s/ Xxxxxxx X. Xxxxx
		Xxxxxxx X. Xxxxx, Chairman

Accepted:

/s/ Xxxxxxx X. Xxx

Xxxxxxx W. Xxx, CEO & President

000 X. Xxxxxxx Xxxx.

Chicago, Illinois 60604 -2994

000 000-0000

Fax: 000 000-0000

Email: xxxx00@xxxx.xxx