SEC Form 4 · Updated Daily
CCOI
— COGENT COMMUNICATIONS HOLDINGS, INC. OwnershipInsider and institutional ownership derived from SEC Form 4 filings. Click any owner to see their holdings across every company they’ve filed on, and how their position has changed over time.
Current Reporting Owners
| Owner | Role | Shares Owned | As Of | Last Activity |
|---|---|---|---|---|
| OAK INVESTMENT PARTNERS IX L P | Reporting Owner | 3,711,469 | 2006-06-07 | S |
| OAK IX AFFILIATES FUND LP | Reporting Owner | 3,711,469 | 2006-06-07 | S |
| OAK IX AFFILIATES FUND A LP | Reporting Owner | 3,711,469 | 2006-06-07 | S |
| OAK MANAGEMENT CORP | 10%+ Owner | 3,711,469 | 2006-06-07 | S |
| SCHAEFFER DAVE | Director · Officer | 1,609,143 | 2026-05-04 | A |
| WEED THADDEUS GERARD | Officer | 193,050 | 2026-09-02 | S |
| Chang John B. | Officer | 188,847 | 2025-12-31 | A |
| Harris Mark Andrew | Officer | 110,168 | 2025-12-31 | A |
| Montagner Marc | Officer | 103,287 | 2026-09-30 | A |
| Karnes Jeffrey | Officer | 72,218 | 2013-05-01 | S |
| LIEBHABER RICHARD | Director | 67,845 | 2019-10-01 | A |
| BROOKS STEVEN D | Director | 62,138 | 2026-09-30 | A |
| KUMMER RAYMOND B | Officer | 60,000 | 2023-01-03 | A |
| BUBECK JAMES | Officer | 55,142 | 2025-06-04 | S |
| Harrison R Reed | Officer | 55,000 | 2009-09-10 | M |
| BEURY ROBERT N JR | Officer | 41,440 | 2019-05-01 | A |
| Ortega Ernest | Officer | 38,800 | 2015-09-16 | S |
| de Sa Paul | Director | 37,237 | 2026-09-30 | A |
| KILMER HENRY W | Officer | 36,200 | 2026-09-15 | S |
| Howell Deneen C | Director | 35,775 | 2026-09-30 | A |
| ONEILL TIMOTHY G | Officer | 33,600 | 2021-06-02 | S |
| Howard Eve N | Director | 30,751 | 2026-09-30 | A |
| Wallace Sean R. | Officer | 29,225 | 2022-03-02 | S |
| WEINGARTEN TIM | Reporting Owner | 28,111 | 2019-10-01 | A |
| FERGUSON Lewis H | Director | 27,984 | 2026-09-30 | A |
| Kennedy Sheryl Lynn | Director | 17,135 | 2026-09-30 | A |
| Danielson Jeffrey S | Officer | 16,000 | 2023-08-02 | — |
| O'Connor Greg W | Officer | 16,000 | 2023-05-03 | A |
| KATZ CAROLYN | Director | 15,750 | 2021-10-01 | A |
| Bath Blake | Director | 12,606 | 2025-03-31 | A |
| GLASSMEYER EDWARD F | Director | 11,250 | 2007-01-08 | A |
| Kapp David Allen | Officer | 10,600 | 2023-08-10 | S |
| Slagmuylder Jean-Michel F.F. | Officer | 9,141 | 2020-03-17 | — |
| SCHLEIFER MARK A | Officer | 3,125 | 2011-12-02 | M |
| MARGALIT EREL N | Director | 2,500 | 2013-07-01 | A |
| PETERSON KENNETH D JR | Director | 0 | 2007-03-23 | D |
| General Business Finance & Investments, Ltd. | 10%+ Owner | 0 | 2007-03-23 | S |
| BERTRAND JEAN JACQUES | Director | 0 | 2007-03-23 | S |
| BNP EUROPE TE LECOM & MEDIA FUND II LP | 10%+ Owner | 0 | 2007-03-23 | S |
Recent Filings
| Date | Owner | Activity | Shares | Price | Owned After |
|---|---|---|---|---|---|
| 2026-09-30 | BROOKS STEVEN D | Grant / award | 3,445 | $0.00 | 62,138 |
| 2026-09-30 | de Sa Paul | Grant / award | 3,445 | $0.00 | 37,237 |
| 2026-09-30 | FERGUSON Lewis H | Grant / award | 3,445 | $0.00 | 27,984 |
| 2026-09-30 | Howard Eve N | Grant / award | 3,445 | $0.00 | 30,751 |
| 2026-09-30 | Howell Deneen C | Grant / award | 3,445 | $0.00 | 35,775 |
| 2026-09-30 | Kennedy Sheryl Lynn | Grant / award | 3,445 | $0.00 | 17,135 |
| 2026-09-30 | Montagner Marc | Grant / award | 3,445 | $0.00 | 103,287 |
| 2026-09-15 | KILMER HENRY W | Open-market sale | 2,400 | $9.21 | 36,200 |
| 2026-09-02 | WEED THADDEUS GERARD | Open-market sale | 4,850 | $9.37 | 193,050 |
| 2026-06-30 | Montagner Marc | Grant / award | 3,445 | $0.00 | 99,842 |
| 2026-06-30 | Kennedy Sheryl Lynn | Grant / award | 3,445 | $0.00 | 13,690 |
| 2026-06-30 | FERGUSON Lewis H | Grant / award | 3,445 | $0.00 | 24,539 |
| 2026-06-30 | Howard Eve N | Grant / award | 3,445 | $0.00 | 27,306 |
| 2026-06-30 | de Sa Paul | Grant / award | 3,445 | $0.00 | 33,792 |
| 2026-06-30 | BROOKS STEVEN D | Grant / award | 3,445 | $0.00 | 58,693 |
| 2026-06-30 | Howell Deneen C | Grant / award | 3,445 | $0.00 | 32,330 |
| 2026-06-16 | WEED THADDEUS GERARD | Open-market sale | 4,850 | $16.79 | 197,900 |
| 2026-06-15 | KILMER HENRY W | Open-market sale | 2,400 | $17.01 | 38,600 |
| 2026-05-28 | FERGUSON Lewis H | Open-market sale | 2,800 | $20.36 | 21,094 |
| 2026-05-14 | Kennedy Sheryl Lynn | Open-market sale | 3,300 | $16.22 | 10,245 |
| 2026-05-04 | SCHAEFFER DAVE | Gift | 1,000,000 | $0.00 | 1,258,990 |
| 2026-05-04 | SCHAEFFER DAVE | Gift | 1,000,000 | $0.00 | 609,143 |
| 2026-05-04 | SCHAEFFER DAVE | Grant / award | 1,000,000 | $0.00 | 1,609,143 |
| 2026-04-01 | SCHAEFFER DAVE | Gift | 29,333 | $0.00 | 258,990 |
| 2026-04-01 | SCHAEFFER DAVE | Gift | 29,333 | $0.00 | 609,143 |
| 2026-04-01 | SCHAEFFER DAVE | Disposition to issuer | 58,667 | $0.00 | 638,476 |
| 2026-03-31 | BROOKS STEVEN D | Grant / award | 3,445 | $0.00 | 55,248 |
| 2026-03-31 | de Sa Paul | Grant / award | 3,445 | $0.00 | 30,347 |
| 2026-03-31 | FERGUSON Lewis H | Grant / award | 3,445 | $0.00 | 23,894 |
| 2026-03-31 | Howard Eve N | Grant / award | 3,445 | $0.00 | 23,861 |
| 2026-03-31 | Howell Deneen C | Grant / award | 3,445 | $0.00 | 28,885 |
| 2026-03-31 | Kennedy Sheryl Lynn | Grant / award | 3,445 | $0.00 | 13,545 |
| 2026-03-31 | Montagner Marc | Grant / award | 3,445 | $0.00 | 96,397 |
| 2026-03-06 | KILMER HENRY W | Open-market sale | 2,400 | $23.35 | 41,000 |
| 2026-03-05 | WEED THADDEUS GERARD | Open-market sale | 4,850 | $22.63 | 202,750 |
| 2026-03-05 | Kennedy Sheryl Lynn | Open-market sale | 3,300 | $22.99 | 10,100 |
| 2026-03-05 | FERGUSON Lewis H | Open-market sale | 2,206 | $23.03 | 20,449 |
| 2025-12-31 | Chang John B. | Grant / award | 100,000 | $0.00 | 188,847 |
| 2025-12-31 | Chang John B. | Grant / award | 9,600 | $0.00 | 88,847 |
| 2025-12-31 | Harris Mark Andrew | Grant / award | 100,000 | $0.00 | 110,168 |
Source: SEC EDGAR Form 4 filings. For informational purposes only — not investment advice.