LIMITED POWER OF ATTORNEY 
FOR SECTION 16 REPORTING OBLIGATIONS
The undersigned hereby constitutes and appoints each of Annemarie Tierney and 
Steven Vigliotti, and their designees, severally, as the undersigned's true and lawful 
attorneys-in-fact and agents, with full power of substitution or revocation, for the 
undersigned and in the undersigned's name, place and stead, to: 
(1)        execute for and on behalf of the undersigned, in the undersigned's capacity as an 
officer and/or director of NYFIX, Inc. (the "Company"), Forms 3, 4, and 5 
(including any amendments thereto) in accordance with Section 16(a) of the 
Securities Exchange Act of 1934, as amended, and the rules promulgated 
thereunder (the "Exchange Act"); 
(2)        do and perform any and all acts for and on behalf of the undersigned which may 
be necessary or desirable to prepare, complete and execute any such Form 3, 4, or 
5 or any amendment or amendments thereto, and timely deliver and file any such 
Form with the United States Securities and Exchange Commission and any stock 
exchange or similar authority; and 
      
(3)        seek or obtain, as the undersigned's representative and on the undersigned's 
behalf, information regarding transactions in the Company's securities from any 
third party, including brokers, employee benefit plan administrators and trustees, 
and the undersigned hereby authorizes any such person to release any such 
information to such attorney-in-fact and approves and ratifies any such release of 
information; and
(4)        take any other action of any type whatsoever in connection with the foregoing 
which, in the opinion of such attorney-in-fact, may be of benefit to, in the best 
interest of, or legally required by, the undersigned, it being understood that the 
documents executed by such attorney-in-fact on behalf of the undersigned 
pursuant to this Power of Attorney shall be in such form and shall contain such 
terms and conditions as such attorney-in-fact may approve in such attorney-in-
fact's discretion. 
      
      The undersigned hereby grants to each such attorney-in-fact full power and 
authority to do and perform each and every act and thing requisite, necessary, or proper 
to be done in the exercise of any of the rights and powers herein granted, as fully to all 
intents and purposes as the undersigned might or could do in person, with full power of 
substitution and revocation, hereby ratifying and confirming all that such attorney-in-fact, 
or such attorney-in-fact's substitute, substitutes, designee or designees shall lawfully do 
or cause to be done by virtue of this Power of Attorney and the rights and powers herein 
granted. 
      
      The undersigned acknowledges that the foregoing attorneys-in-fact, in serving in 
such capacity at the request of the undersigned, are not assuming nor relieving, nor is the 
Company assuming nor relieving, any of the undersigned's responsibilities to comply 
with Section 16 of the Exchange Act.  The undersigned acknowledges that neither the 
Company nor the foregoing attorneys-in-fact assume (i) any liability for the 
undersigned's responsibility to comply with the requirements of the Exchange Act, (ii) 
any liability of the undersigned for any failure to comply with such requirements, or (iii) 
any obligation or liability of the undersigned for profit disgorgement under Section 16(b) 
of the Exchange Act. 
      
      This Power of Attorney shall remain in full force and effect until the undersigned 
is no longer required to file Forms 3, 4, and 5 under Section 16 of the Exchange Act with 
respect to the undersigned's holdings of and transactions in securities issued by the 
Company, unless earlier revoked by the undersigned in a signed writing delivered to the 
foregoing attorneys-in-fact. 
      
      IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to 
be executed as of this 4th day of February, 2008. 
      
      
      /s/ Mitchel Lenson