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EXHIBIT 10.3

6715 Kenilworth Avenue Partnership
1015 31st Street, NW
Washington, DC 20007

Reference: Lease Agreement dated Sept. 1, 2000
Extension of Lease Agreement dated August 1, 2001
Amendment to Lease Agreement dated Oct. 29, 2001
Amendment to Lease Agreement dated May 1, 2002

July 24, 2002 Amendment to Lease Agreement

        Cogent Communications, Inc. (Tenant) and 6715 Kenilworth Avenue
Partnership (Landlord) hereby agree to extend the Lease Term of the Lease
Agreement dated September 1, 2001, as amended (Lease Agreement) for an
additional 12 months commencing September 1, 2002 and expiring August 31, 2003
for 17,692 square feet at a Fixed Annual Rent of $24 per square foot ($424,608),
payable in twelve (12) equal monthly installments of $35,384, as indicated
below:

Rent Payment

        
      
1015 31st St

Floor

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  Square Feet

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    3     2,323     4     5,123     5     5,123     6     5,123        

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Total Sq. Feet         17,692        

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Total Annual Rent       $ 424,608        

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Total Monthly Rent       $ 35,384        

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        Except as amended herein, the Lease Agreement, as amended, shall remain
in full force and effect.

 
 
  TENANT: Cogent Communications, Inc
 
 
  /s/Thaddeus G. Weed

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Thaddeus G. Weed
Vice President, Controller    
 
 
  LANDLORD: 6715 Kenilworth Avenue Partnership
 
 
  /s/Dave Schaeffer

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Dave Schaeffer
General Partner
   

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EXHIBIT 10.3