EX-32.2 5 y57778exv32w2.htm EX-32.2: CERTIFICATION EX-32.2
Exhibit 32.2
Certification Under Section 906 of the Sarbanes-Oxley Act of 2002
(United States Code, Title 18, Chapter 63, Section 1350)
Accompanying Quarterly Report on Form 10-Q of
MarketAxess Holdings Inc. for the Quarter Ended March 31, 2008
     In connection with the Quarterly Report on Form 10-Q of MarketAxess Holdings Inc. (the “Company”) for the quarter ended March 31, 2008 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, James N.B. Rucker, Chief Financial Officer of the Company, hereby certify, pursuant to 18 U.S.C. Section 1350, that:
(1)   The Report fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934; and
 
(2)   The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.
         
     
  /s/ JAMES N.B. RUCKER    
  James N.B. Rucker    
  Chief Financial Officer   
 
May 12, 2008
     This certification shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, or otherwise subject to the liability of that section, nor shall it be deemed to be incorporated by reference into any filing under the Securities Act of 1933 or the Securities Exchange Act of 1934, except to the extent the Company specifically incorporates it by reference.

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