Sec Form 4 Filing - MARGALIT EREL N @ COGENT COMMUNICATIONS GROUP INC - 2005-02-15

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person MARGALIT EREL N 2. Issuer Name and Ticker or Trading Symbol COGENT COMMUNICATIONS GROUP INC [ COI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner _____ Officer (give title below) X __ Other (specify below) DIRECTOR & 10% OWNER (Last) (First) (Middle) 41 MADISON AVENUE, 25TH FLOOR 3. Date of Earliest Transaction (MM/DD/YY) 02/15/2005 (Street) NEW YORK, NY10010 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 02/15/2005 C 43,902,631 A 45,490,129 D ( 1 ) Common Stock 02/15/2005 C 3,374,970 A 3,497,000 D ( 3 ) Common Stock 02/15/2005 C 1,230,464 A 1,274,884 D ( 2 )

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Series M Participating Convertible Preferred Stock ( 4 ) 02/15/2005 C 90.5 ( 4 ) ( 4 ) Common Stock 2,805,332 ( 4 ) 0 D ( 1 ) Series M Participating Convertible Preferred Stock ( 4 ) 02/15/2005 C 7 ( 4 ) ( 4 ) Common Stock 216,987 ( 4 ) 0 D ( 3 ) Series M Participating Convertible Preferred Stock ( 4 ) 02/15/2005 C 2.5 ( 4 ) ( 4 ) Common Stock 77,495 ( 4 ) 0 D ( 2 ) Series J Participating Convertible Preferred Stock ( 6 ) 02/15/2005 C 45.2 ( 6 ) ( 6 ) Common Stock 1,401,116 ( 6 ) 0 D ( 1 ) Series J Participating Convertible Preferred Stock ( 6 ) 02/15/2005 C 3.4 ( 6 ) ( 6 ) Common Stock 105,394 ( 6 ) 0 D ( 3 ) Series J Participating Convertible Preferred Stock ( 6 ) 02/15/2005 C 1.4 ( 6 ) ( 6 ) Common Stock 43,397 ( 6 ) 0 D ( 2 ) Series G Participating Convertible Preferred Stock ( 7 ) 02/15/2005 C 2,263 ( 7 ) ( 7 ) Common Stock 39,696,183 ( 7 ) 0 D ( 1 ) Series G Participating Convertible Preferred Stock ( 7 ) 02/15/2005 C 174 ( 7 ) ( 7 ) Common Stock 3,052,589 ( 7 ) 0 D ( 3 ) Series G Participating Convertible Preferred Stock ( 7 ) 02/15/2005 C 63 ( 7 ) ( 7 ) Common Stock 1,109,572 ( 7 ) 0 D ( 2 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other MARGALIT EREL N 41 MADISON AVENUE 25TH FLOOR NEW YORK, NY10010 DIRECTOR & 10% OWNER JERUSALEM VENTURE PARTNERS III LP 41 MADISON AVENUE 25TH FLOOR NEW YORK, NY10010 X JERUSALEM VENTURE PARTNERS ENTREPRENEUR FUND III LP 41 MADISON AVENUE 25TH FLOOR NEW YORK, NY10010 X JERUSALEM VENTURE PARTNERS III ISRAEL LP JERUSALEM TECHNOLOGY PARK BUILDING 1 MALHA, JERUSALEM, L391487 X JERUSALEM PARTNERS II I LP 41 MADISON AVENUE 25TH FLOOR NEW YORK, NY10010 X JERUSALEM VENTURE PARTNERS III ISRAEL MANAGEMENT CO LTD JERUSALEM TECHNOLOGY PARK BUILDING 1 MALHA, JERUSALEM, L391487 X JERUSALEM VENTURE PARTNERS CORP C/O MAPLES & CALDER P.O. BOX 309 GT, GRAND CAYMAN, E9 X Signatures Jerusalem Venture Partners III, L.P., by Jerusalem Partners III, L.P., its general partner, by Jerusalem Venture Partners Corporation, its general partner, by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Jerusalem Venture Partners Entrepreneur Fund III, L.P., by Jerusalem Partners III, L.P., its general partner, by Jerusalem Venture Partners Corporation, its general partner, by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Jerusalem Venture Partners III (Israel), L.P., by Jerusalem Venture Partners (Israel) III Management Company Ltd., its general partner, by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Jerusalem Venture Partners (Israel) III Management Company Ltd., by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Jerusalem Partners III, L.P., by Jerusalem Venture Partners Corporation, its general partner, by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Jerusalem Venture Partners Corporation, by Erel Margalit, its officer 02/15/2005 Signature of Reporting Person Date Erel Margalit 02/15/2005 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Shares are owned directly by Jerusalem Venture Partners III, L.P. Erel N. Margalit, the Designated Filer, is a director of the Issuer and an officer of Jerusalem Venture Partners Corporation, which serves as the general partner to Jerusalem Partners III, L.P. (the general partner of Jerusalem Venture Partners III, L.P.), and may be deemed the indirect beneficial owner of the reported shares of such entity but disclaims beneficial ownership in the shares held by the other joint filers, except to the extent of his pecuniary interest therein. ( 2 )Shares are owned directly by Jerusalem Venture Partners III (Israel), L.P. Erel N. Margalit, the Designated Filer, is a director of the Issuer and an officer of Jerusalem Venture Partners (Israel) III Management Company, Ltd., which serves as the general partner to Jerusalem Venture Partners III (Israel), L.P., and may be deemed the indirect beneficial owner of the reported shares of such entity but disclaims beneficial ownership in the shares held by the other joint filers, except to the extent of his pecuniary interest therein. ( 3 )Shares are owned directly by Jerusalem Venture Partners Entrepreneur Fund III, L.P. Erel N. Margalit, the Designated Filer, is a director of the Issuer and an officer of Jerusalem Venture Partners Corporation, which serves as the general partner to Jerusalem Partners III, L.P. (the general partner of Jerusalem Venture Partners Entrepreneur Fund III, L.P.), and may be deemed the indirect beneficial owner of the reported shares of such entity but disclaims beneficial ownership in the shares held by the other joint filers, except to the extent of his pecuniary interest therein. ( 4 )Each share of Series M Participating Convertible Preferred Stock converted into the number of shares of Common Stock indicated in column 7. ( 5 )Converted into Common Stock pursuant to Conversion and Lock-Up Letter Agreement. ( 6 )Series J Participating Convertible Preferred Stock converted into the number of shares of Common Stock indicated in column 7. ( 7 )Series G Participating Convertible Preferred Stock converted into the number of shares of Common Stock indicated in column 7.

Remarks: Erel N. Margalit, the Designated Filer, is a director of the issuer and an officer of both Jerusalem Venture Partners Corporation and Jerusalem Venture Partners (Israel) III Management Company, Ltd. Jerusalem Venture Partners Corporation serves as the general partner to Jerusalem Partners III, L.P. Jerusalem Partners III, L.P. serves as the general partner to Jerusalem Venture Partners III, L.P. and Jerusalem Venture Partners Entrepreneur Fund III, L.P. Jerusalem Venture Partners (Israel) III Management Company Ltd. serves as the general partner to Jerusalem Venture Partners III (Israel), L.P. Each Reporting Person disclaims the existence of a "group" and disclaims beneficial ownership of any securities (except to the extent of such Reporting Person's pecuniary interest in such securities) other than any securities reported herein as being directly owned by such Reporting Person, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of any securities for purposes of Section 16 or for any other purpose.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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