Exhibit
10.18

    


    December
31, 2008

    


    PERSONAL
& CONFIDENTIAL

    


    C. Thomas
Richardson

    [Home
address redacted]

    


    
      	
              Re:

            	
              Employment
      Agreement dated January 4, 2008 between you and NYFIX,
  Inc.

            


    

    (the
“Agreement”).

    


    Dear
Tom:

    


    You and
NYFIX, Inc. agree to the following amendments to the Agreement.

    


    
      	
            	
              1.

            	
              The
      sixth sentence of the last full paragraph (such paragraph beginning with
      the words “While we certainly hope”) beginning on Page 4 of your agreement
      (such sentence beginning with the words “Notwithstanding the above, in the
      event you terminate your employment for ‘Good Reason’”) is amended as
      follows:

            


    

    


    
      	
               
      

            	
              a.

            	
              The
      words “provided you sign a Release containing generally the release
      language attached as Attachment E to this Agreement (the “Release”)” are
      deleted;

            


    

    
      	
               
      

            	
              b.

            	
              The
      words ” , subject to Attachment C,” are inserted prior to the words “(i)
      twelve (12) months’ Base Salary”;

            


    

    
      	
               
      

            	
              c.

            	
              Subparagraph
      (i) of such sentence is amended by adding the words “and commencing 30
      days following the termination of employment” prior to the
      semicolon;

            


    

    
      	
               
      

            	
              d.

            	
              Subparagraph
      (ii) of such sentence is amended by adding the words “payable in a lump
      sum within 30 days of your termination” prior to the
      semicolon;

            


    

    
      	
               
      

            	
              e.

            	
              The
      words “but not later than March 15 of the applicable following year”
      appearing at the end of such sentence are deleted and replaced by the
      words “but not later than March 15 of the year following
      termination.”

            


    

    


    
      	
            	
              2.

            	
              The
      seventh sentence of the last full paragraph beginning on Page 4 of your
      agreement (such sentence beginning with the words “Alternatively, in the
      event you terminate your employment for Good Reason”) is amended as
      follows:

            


    


    
      
         


      

      
        Page 1 of
5

        
          

        

      

      
         


      

    


    
      	
               
      

            	
              a.

            	
              The
      words “payable in accordance with the Company’s normal payroll practices
      and commencing 30 days following termination of your employment,” are
      inserted before the words “less required
  withholdings”;

            


    

    
      	
               
      

            	
              b.

            	
              The
      words “provided you execute a Release containing generally the release
      language attached as Attachment E to this Agreement” appearing after the
      words “less required withholdings” are
deleted.

            


    

    


    
      	
            	
              3.

            	
              A
      new (eighth) sentence is inserted after the seventh sentence of such
      paragraph, to read in full as
follows:

            


    

    


    “Your
severance payments and benefits provided above shall be made or shall commence
according to the terms of this Agreement on the 30th day
after your termination, provided that you execute a release containing the
general release language attached as Attachment E to this Agreement (the
“Release”), and that Release has become binding and any applicable revocation
period has lapsed as of such date.”

    


    
      	
            	
              4.

            	
              A
      new (tenth) sentence is inserted at the end of such paragraph, to read in
      full as follows:

            


    

    


    “The
distribution of the payments and benefits you receive upon your termination of
employment with the Company shall be subject to the terms and conditions set
forth in Attachment C.”

    


    
      	
            	
              5.

            	
              Attachment
      C is amended to read in its entirety as set forth in the attachment
      hereto.

            


    

    


    If you
are in agreement with the foregoing, kindly execute a copy of this letter and
return it to the undersigned.


    
      
         


      

      
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                NYFIX,
      Inc.

              
	 
      	 
      	 
      
	 
      	 
      	
                Very
      truly yours,

              
	 
      	 
      	
                /s/ Steven Vigliotti

              
	 
      	 
      	
                Steven
      Vigliotti

              
	 
      	 
      	
                Chief
      Financial Officer

              
	
                Accepted
      and Agreed:

              	 
      	 
      
	 
      	 
      	 
      
	
                /s/ C. Thomas Richardson

              	 
      	 
      
	
                C.
      Thomas Richardson

              	 
      	 
      
	
                December 31, 2008

              	 
      	 
      


      

    


    
      
         


      

      
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    Attachment
C

    


    Payments Subject to Section
409A

     

    The
parties mutually agree to cooperate on the application of 409A to the
agreement.  Subject to the provisions in this Attachment C, severance
payments or benefits under this offer letter shall begin only upon the date of
your “separation from service” (determined as set forth below) which occurs on
or after the date of termination of employment.  The following rules
shall apply with respect to distribution of the payments and benefits, if any,
to be provided to you under this offer letter:

     

    
      	
              (a)

            	
              It
      is intended that each installment of the severance payments and benefits
      provided under this offer letter shall be treated as a separate “payment”
      for purposes of Section 409A of the Internal Revenue Code and the guidance
      issued thereunder (“Section 409A”).  Neither you nor the Company
      shall have the right to accelerate or defer the delivery of any such
      payments or benefits except to the extent specifically permitted or
      required by Section 409A.

            


    

     

    
      	
              (b)

            	
              If,
      as of the date of your “separation from service” from the Company, you are
      not a “specified employee” (within the meaning of Section 409A), then each
      installment of the severance payments and benefits shall be made on the
      dates and terms set forth in this offer
letter.

            


    

     

    
      	
              (c)

            	
              If,
      as of the date of your  “separation from service” from the
      Company, you are a “specified employee” (within the meaning of Section
      409A), then:

            


    

     

    
      	
            	
              (i)

            	
              Each
      installment of the severance payments and benefits due under this offer
      letter that, in accordance with the dates and terms set forth herein, will
      in all circumstances, regardless of when the separation from service
      occurs, be paid within the short-term deferral period (as defined under
      Section 409A) shall be treated as a short-term deferral within the meaning
      of Treasury Regulation Section 1.409A-1(b)(4) to the maximum extent
      permissible under Section 409A; and

            


    

     

    
      	
            	
              (ii)

            	
              Each
      installment of the severance payments and benefits due under this offer
      letter that is not described in paragraph (i) above and that would, absent
      this subsection, be paid within the six-month period following your
      “separation from service” from the Company shall not be paid until the
      date that is six months and one day after such separation from service
      (or, if earlier, your death), with any such installments that are required
      to be delayed being accumulated during the six-month period and paid in a
      lump sum on the date that is six months and one day following your
      separation from service and any subsequent installments, if any, being
      paid in accordance with the dates and terms set forth herein; provided,
      however, that the preceding provisions of this sentence shall not apply to
      any installment of severance payments and benefits if and to the maximum
      extent that that such installment is deemed to be paid under a separation
      pay plan that does not provide for a deferral of compensation by reason of
      the application of Treasury Regulation 1.409A-1(b)(9)(iii) (relating to
      separation pay upon an involuntary separation from
      service).  Any installments that qualify for the exception under
      Treasury Regulation Section 1.409A-1(b)(9)(iii) must be paid no later than
      the last day of your second taxable year following the taxable year in
      which the separation from service
occurs.

            


    


    
      
         


      

      
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              (d)

            	
              The
      determination of whether and when your separation from service from the
      Company has occurred shall be made and in a manner consistent with, and
      based on the presumptions set forth in, Treasury Regulation Section
      1.409A-1(h).  Solely for purposes of this paragraph (d),
      “Company” shall include all persons with whom the Company would be
      considered a single employer as determined under Treasury Regulation
      Section 1.409A-(h)(3).

            


    

     

    
      	
              (e)

            	
              All
      reimbursements and in-kind benefits provided under this offer letter shall
      be made or provided in accordance with the requirements of Section 409A to
      the extent that such reimbursements or in-kind benefits are subject to
      Section 409A, including, where applicable, the requirement that (i) any
      reimbursement is for expenses incurred during your lifetime (or during a
      shorter period of time specified in this offer letter), (ii) the amount of
      expenses eligible for reimbursement during a calendar year may not affect
      the expenses eligible for reimbursement in any other calendar year, (iii)
      the reimbursement of an eligible expense will be made on or before the
      last day of the calendar year following the year in which the expense is
      incurred and (iv) the right to reimbursement is not subject to set off or
      liquidation or exchange for any other
benefit.

            


    

     

    
      	
              (f)

            	
              The
      Company may withhold (or cause to be withheld) from any payments made
      under this offer letter, all federal, state, city or other taxes as shall
      be required to be withheld pursuant to any law or governmental regulation
      or ruling.

            


    

     

    
      
         


      

      
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