| Date | Name | Symbol | Type | Security | Shares | Price | Value | Ownership | Reported |
| 10/01/2023 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.4k | $0.00 | $0 | | 10/01/2023 |
| 07/01/2023 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.4k | $0.00 | $0 | | 07/01/2023 |
| 04/01/2023 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.5k | $0.00 | $0 | | 04/01/2023 |
| 01/03/2023 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.7k | $0.00 | $0 | | 01/03/2023 |
| 10/01/2022 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.6k | $0.00 | $0 | | 10/01/2022 |
| 07/01/2022 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.5k | $0.00 | $0 | | 07/01/2022 |
| 04/01/2022 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.5k | $0.00 | $0 | | 04/01/2022 |
| 10/01/2021 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 10/01/2021 |
| 08/09/2021 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 8.8k | $77.69 | $679.8k | | 08/09/2021 |
| 01/01/2021 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 01/01/2021 |
| 10/01/2020 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 10/01/2020 |
| 07/01/2020 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 07/01/2020 |
| 04/01/2020 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 04/01/2020 |
| 03/05/2020 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 5.5k | $86.45 | $475.5k | | 03/05/2020 |
| 01/01/2020 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 01/01/2020 |
| 12/05/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 200 | $62.45 | $12.5k | | 12/04/2019 |
| 12/05/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 200 | $62.45 | $12.5k | | 12/04/2019 |
| 12/04/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 3.8k | $62.31 | $236.8k | | 12/04/2019 |
| 12/04/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 3.8k | $62.31 | $236.8k | | 12/04/2019 |
| 10/01/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 10/01/2019 |
| 07/01/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 07/01/2019 |
| 05/09/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 10k | $57.88 | $578.8k | | 05/09/2019 |
| 04/01/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 04/01/2019 |
| 01/01/2019 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 01/01/2019 |
| 10/01/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 10/01/2018 |
| 09/13/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 3.6k | $54.94 | $197.2k | | 09/13/2018 |
| 09/12/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 7.4k | $55.03 | $407.9k | | 09/11/2018 |
| 09/11/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Sale | common stock | 11k | $54.86 | $603.4k | | 09/11/2018 |
| 07/01/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 07/01/2018 |
| 04/01/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 04/01/2018 |
| 01/01/2018 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 01/01/2018 |
| 07/01/2017 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 07/01/2017 |
| 01/01/2017 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.8k | $0.00 | $0 | | 01/01/2017 |
| 10/01/2015 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.9k | $0.00 | $0 | | 10/01/2015 |
| 07/01/2015 | COGENT COMMUNICATIONS HOLDINGS, INC. | CCOI | Grant | common stock | 1.9k | $0.00 | $0 | | 07/01/2015 |
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