| OC | Olive Resource Capital Inc | 0.1000 | 0.1000 | 0.1000 | 21.0K | 0.0050 | | 5.26 | |
| ODV.WT.V | Osisko Development Corp WT V USD | 1.380 | 1.380 | 1.380 | 15.0K | -0.320 | | 18.82 | |
| OML | Omni-Lite Industries Canada Inc | 1.440 | 1.440 | 1.440 | 3.8K | -0.060 | | 4.00 | |
| OMM | Omineca Mining and Metals Ltd | 0.1000 | 0.0900 | 0.1000 | 351.5K | 0.0100 | | 11.11 | |
| ORCL | Oracle Commodity Holding Corp | 0.0650 | 0.0550 | 0.0650 | 923.7K | 0.0100 | | 18.18 | |
| OTC | Ocumetics Technology Corp | 0.5500 | 0.5300 | 0.5500 | 36.8K | 0.0100 | | 1.85 | |