| 2013-06-13 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 2,500 0.0054% | $27.95 | $69,875 | +27.77% | |
| 2013-02-27 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 5,000 0.0109% | $24.98 | $124,899 | +26.76% | |
| 2013-02-26 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 15,500 0.0338% | $24.96 | $386,880 | +26.68% | |
| 2011-12-15 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 13,000 0.0298% | $16.97 | $220,605 | +15.74% | |
| 2011-11-30 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 8,700 0.0187% | $16.55 | $143,976 | +10.46% | |
| 2010-01-07 | Cogent Communications Holdings, Inc. CCOI | director | 8,700 0.0266% | $14.18 | $123,366 | -2.88% | ||
| 2010-01-06 | Cogent Communications Holdings, Inc. CCOI | director | 7,140 0.016% | $10.50 | $74,946 | -3.71% | ||
| 2009-01-05 | Cogent Communications Holdings, Inc. CCOI | director | 11,360 0.0261% | $6.60 | $74,976 | +25.45% | ||
| 2008-02-29 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 15,000 0.0319% | $19.14 | $287,066 | -52.93% | |
| 2007-03-23 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 592,938 1.1833% | $23.41 | $13.88M | +0.77% | |
| 2007-01-22 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 200,002 0.4105% | $19.69 | $3.94M | +23.5% | |
| 2007-01-19 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.6105% | $19.74 | $5.92M | +22.14% | |
| 2007-01-18 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.6196% | $19.93 | $5.98M | +22.59% | |
| 2007-01-17 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.6161% | $20.40 | $6.12M | +19.05% | |
| 2007-01-16 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.614% | $20.39 | $6.12M | +18.7% | |
| 2007-01-12 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.6111% | $20.35 | $6.1M | +18.85% | |
| 2007-01-11 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 300,000 0.5842% | $19.12 | $5.74M | +20.69% | |
| 2006-11-14 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 3.2M 5.9362% | $14.64 | $46.85M | +49.57% | |
| 2006-06-06 | Sale | Cogent Communications Holdings, Inc. CCOI | director | 1.8M 3.7034% | $8.53 | $15.35M | +73.45% |