SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 ---------- SCHEDULE 13G (RULE 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1(b) (c), AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(b) (AMENDMENT NO.__1___)(1) Cogent Communications Group, Inc. ------------------------------------------------------------- (Name of Issuer) Common Stock, Par Value $0.001 per share ------------------------------------------------------------- (Title of Class of Securities) 19239V104 ------------------------------------------------------------- (CUSIP Number) December 31, 2002 ------------------------------------------------------------- (Date of Event which requires filing of this Statement) Check the appropriate box to designate the Rule pursuant to which this Schedule is filed: / / Rule 13d-1(b) / / Rule 13d-1(c) /X/ Rule 13d-1(d) ---------- (1) The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). Cusip No. 19239V104 13G Page 2 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak Investment Partners IX, Limited Partnership 06-1556218 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power 1,960,865 Shares of Common Stock Number of 6. Shared Voting Power Shares Not applicable Beneficially Owned by Each 7. Sole Dispositive Power Reporting 1,960,865 Shares of Common Stock Person With: 8. Shared Dispositive Power Not applicable 9. Aggregate Amount Beneficially Owned by Each Reporting Person 1,960,865 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.4% 12. Type of Reporting Person* PN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 3 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak Associates IX, LLC 06-1556230 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 1,960,865 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 1,960,865 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 1,960,865 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.4% 12. Type of Reporting Person* OO-LLC SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 4 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak IX Affiliates Fund - A, Limited Partnership 06-1571899 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power 47,066 Shares of Common Stock Number of 6. Shared Voting Power Shares Not applicable Beneficially Owned by Each 7. Sole Dispositive Power Reporting 47,066 Shares of Common Stock Person With: 8. Shared Dispositive Power Not applicable 9. Aggregate Amount Beneficially Owned by Each Reporting Person 47,066 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 0.3% 12. Type of Reporting Person* PN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 5 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak IX Affiliates Fund, Limited Partnership 06-1556229 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power 20,900 Shares of Common Stock Number of 6. Shared Voting Power Shares Not applicable Beneficially Owned by Each 7. Sole Dispositive Power Reporting 20,900 Shares of Common Stock Person With: 8. Shared Dispositive Power Not applicable 9. Aggregate Amount Beneficially Owned by Each Reporting Person 20,900 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 0.2% 12. Type of Reporting Person* PN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 6 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak IX Affiliates, LLC 06-1556233 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 67,966 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 67,966 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 67,966 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 0.5% 12. Type of Reporting Person* OO-LLC SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 7 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Oak Management Corporation 06-0990851 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization Delaware 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* CO SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 8 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Bandel L. Carano 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization United States 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* IN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 9 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Gerald R. Gallagher 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization United States 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* IN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 10 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Edward F. Glassmeyer 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization United States 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* IN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 11 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Fredric W. Harman 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization United States 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* IN SEE INSTRUCTIONS BEFORE FILLING OUT! Cusip No. 19239V104 13G Page 12 of 24 1. Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (entities only) Ann H. Lamont 2. Check the Appropriate Box if a Member of a Group* (a) / / (b) /X/ 3. SEC Use Only 4. Citizenship or Place of Organization United States 5. Sole Voting Power Not applicable Number of 6. Shared Voting Power Shares 2,028,831 Shares of Common Stock Beneficially Owned by Each 7. Sole Dispositive Power Reporting Not applicable Person With: 8. Shared Dispositive Power 2,028,831 Shares of Common Stock 9. Aggregate Amount Beneficially Owned by Each Reporting Person 2,028,831 Shares of Common Stock 10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares* / / 11. Percent of Class Represented by Amount in Row (9) 14.9% 12. Type of Reporting Person* IN SEE INSTRUCTIONS BEFORE FILLING OUT! Page 13 of 24 Schedule 13G Amendment No. 1* Common Stock Par Value $0.001 CUSIP No. 19239V104 ITEM 1(a) NAME OF ISSUER: Cogent Communications Group, Inc. ITEM 1(b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES: 1015 31st Street N.W., Suite 330 Washington, DC 20007 ITEM 2(a) NAME OF PERSON FILING: Oak Investment Partners IX, Limited Partnership Oak Associates IX, LLC Oak IX Affiliates Fund - A, Limited Partnership Oak IX Affiliates Fund, Limited Partnership Oak IX Affiliates, LLC Oak Management Corporation Bandel L. Carano Gerald R. Gallagher Edward F. Glassmeyer Fredric W. Harman Ann H. Lamont ITEM 2(b) ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE: c/o Oak Management Corporation One Gorham Island Westport, Connecticut 06880 ITEM 2(c) CITIZENSHIP: Please refer to Item 4 on each cover sheet for each filing person. ITEM 2(d) TITLE OF CLASS OF SECURITIES: Common stock, par value $0.001 per share ITEM 2(e) CUSIP NUMBER: 19239V104 ITEM 3 Not applicable ITEM 4 OWNERSHIP. The approximate percentages of shares of Common Stock reported as beneficially owned by the Reporting Persons is based upon 3,483,898 shares of Common Stock outstanding as of November 8, 2002, as reported in the Issuer's Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2002, plus 2,600,000 shares of Common Stock issuable upon conversion of the Issuer's issued and Page 14 of 24 outstanding Series A Preferred Stock (the "Series A Preferred"), 2,514,046 shares of Common Stock issuable upon conversion of the Issuer's issued and outstanding Series B Preferred Stock (the "Series B Preferred"), and 4,977,340 shares of Common Stock issuable upon conversion of the Issuer's issued and outstanding Series C Preferred Stock (the "Series C Preferred"), all as reported in the Issuer's Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2002. For all computations with respect to this Schedule 13G, the percentage beneficially owned by each reporting person was calculated on a fully diluted, as converted basis of all of the Issuer's issued and outstanding Series A Preferred, Series B Preferred and Series C Preferred, including shares held by third parties. Amounts shown as beneficially owned by each of Oak Investment Partners IX, Limited Partnership ("Oak Investment IX") and Oak Associates IX, LLC, Oak Management Corporation ("Oak Management"), Bandel L. Carano, Edward F. Glassmeyer, Gerald R. Gallagher, Fredric W. Harman, and Ann H. Lamont include the (i) 483,250 shares of Common Stock into which the shares of Series A Preferred held by Oak Investment IX may be converted, (ii) 551,389 shares of Common Stock into which the shares of Series B Preferred held by Oak Investment IX may be converted, and (iii) 926,226 shares of Common Stock into which the shares of Series C Preferred held by Oak Investment IX may be converted. Amounts shown as beneficially owned by each of Oak IX Affiliates Fund-A, Limited Partnership ("Oak Affiliates-A IX"), Oak IX Affiliates, LLC, Oak Management, Bandel L. Carano, Edward F. Glassmeyer, Gerald R. Gallagher, Fredric W. Harman, and Ann H. Lamont include the (i) 11,599 shares of Common Stock into which the shares of Series A Preferred held by Oak Affiliates-A IX may be converted, (ii) 13,235 shares of Common Stock into which the shares of Series B Preferred held by Oak Affiliates-A IX may be converted, and (iii) 22,232 shares of Common Stock into which the shares of Series C Preferred held by Oak Affiliates-A IX may be converted. Amounts shown as beneficially owned by each of Oak IX Affiliates Fund, Limited Partnership ("Oak Affiliates IX"), Oak IX Affiliates, LLC, Oak Management, Bandel L. Carano, Edward F. Glassmeyer, Gerald R. Gallagher, Fredric W. Harman, and Ann H. Lamont include the (i) 5,151 shares of Common Stock into which the shares of Series A Preferred held by Oak Affiliates IX may be converted, (ii) 5,877 shares of Common Stock into which the shares of Series B Preferred held by Oak Affiliates IX may be converted, and (iii) 9,872 shares of Common Stock into which the shares of Series C Preferred held by Oak Affiliates IX may be converted. By making this filing, the Reporting Persons acknowledge that they may be deemed to constitute a "group" within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended, in connection with the securities of the Issuer. Each Reporting Person disclaims the existence of a "group" and disclaims beneficial ownership of all shares of Common Stock or securities convertible into or exercisable for Common Stock other than any shares or other securities reported herein as being owned by it, him or her, as the case may be. Please see Items 5, 6, 7, 8, 9 and 11 for each cover sheet for each filing entity. ITEM 5 OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS. If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: [ ] ITEM 6 OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON. Not applicable Page 15 of 24 ITEM 7 IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY. Not applicable ITEM 8 IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP. Not applicable ITEM 9 NOTICE OF DISSOLUTION OF GROUP. Not applicable ITEM 10 CERTIFICATIONS. Not applicable Page 16 of 24 After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. SIGNATURE: Dated: February 7, 2003 Entities: Oak Investment Partners IX, Limited Partnership Oak Associates IX, LLC Oak IX Affiliates Fund - A, Limited Partnership Oak IX Affiliates Fund, Limited Partnership Oak IX Affiliates, LLC Oak Management Corporation By: /s/ Edward F. Glassmeyer --------------------------------- Edward F. Glassmeyer, as General Partner or Managing Member or as Attorney-in-fact for the above-listed entities Individuals: Bandel L. Carano Gerald R. Gallagher Edward F. Glassmeyer Fredric W. Harman Ann H. Lamont By: /s/ Edward F. Glassmeyer --------------------------------- Edward F. Glassmeyer, Individually and as Attorney-in-fact for the above-listed individuals Page 17 of 24 INDEX TO EXHIBITS Page ---- EXHIBIT A Agreement of Reporting Persons 18 EXHIBIT B Power of Attorney 19