| OBGRF | Orbit Garant Drilling Inc | 0.9730 | 0.7000 | 0.8500 | 52.0K | -0.1455 | | 14.62 | |
| OFED | Oconee Federal Fincl Corp | 17.51 | 17.51 | 17.51 | 400 | -1.49 | | 7.83 | |
| OLVI | Oliveda International Inc | 0.3880 | 0.3302 | 0.3800 | 13.1K | 0.0198 | | 5.50 | |
| OLYFF | Olympia Financial Group Inc | 72.64 | 72.62 | 72.64 | 500 | -5.36 | | 6.88 | |
| OMHI | Om Holdings International Inc | 0.0007 | 0.0007 | 0.0007 | 1.1K | 0.0005 | | 250.00 | |
| ONVC | Online Vacation Ctr Hldgs | 1.980 | 1.980 | 1.980 | 500 | -0.020 | | 1.00 | |
| OPIRQ | Office Properties Income Trust 6.375% | 0.3100 | 0.3100 | 0.3100 | 400 | -0.7200 | | 69.90 | |
| OPITQ | Office Properties Income Trust | 0.0021 | 0.0010 | 0.0015 | 151.7K | -0.0010 | | 40.00 | |
| OPMXF | Operadora DE Sites Mexicn | 0.9800 | 0.8209 | 0.8209 | 24.5K | -0.1691 | | 17.08 | |
| ORLCF | Oracle Commodity Hldg Crp | 0.0244 | 0.0125 | 0.0230 | 2.0K | 0.0018 | | 8.49 | |
| OROVY | Orient Overseas Inr U/Adr | 78.40 | 78.20 | 78.20 | 1.1K | -11.51 | | 12.83 | |
| ORWHF | Oriental Watch Holdings Ltd | 0.4250 | 0.4171 | 0.4250 | 200 | 0.0802 | | 18.66 | |
| OTLC | Oncotelic Therapeutcs Inc | 0.0441 | 0.0369 | 0.0396 | 485.1K | -0.0023 | | 5.49 | |
| OTMCF | Romios Gold Resources Inc | 0.3093 | 0.3093 | 0.3093 | 5.0K | -0.0267 | | 7.95 | |
| OXFYY | Oxford Nanopre Tech U/Adr | 6.500 | 6.500 | 6.500 | 200 | -0.880 | | 11.92 | |
| OZSC | Ozop Energy Solutions Inc | 0.1525 | 0.0900 | 0.1147 | 424.6K | -0.0503 | | 30.48 | |