| OBSJF | Obrascon Huarte Lain Brasil S.A. | 0.5100 | 0.5100 | 0.5100 | 8.0K | 0.0392 | | 8.33 | |
| OERLY | Oc Oerlikon Corp Unsp/Adr | 10.15 | 10.15 | 10.15 | 300 | -0.19 | | 1.84 | |
| OFED | Oconee Federal Fincl Corp | 15.71 | 15.71 | 15.71 | 300 | 0.61 | | 4.04 | |
| OLVI | Oliveda International Inc | 0.4250 | 0.3500 | 0.4250 | 1.4K | 0.0750 | | 21.43 | |
| OMHI | Om Holdings International Inc | 0.0004 | 0.0004 | 0.0004 | 40.0K | 0.0002 | | 100.00 | |
| OMMSF | Omineca Mining & Mtls Ord | 0.0590 | 0.0544 | 0.0544 | 34.0K | 0.0001 | | 0.18 | |
| ONVC | Online Vacation Ctr Hldgs | 2.175 | 2.025 | 2.025 | 600 | -0.075 | | 3.57 | |
| OPIRQ | Office Properties Income Trust 6.375% | 0.2600 | 0.2600 | 0.2600 | 200 | 0.2090 | | 409.80 | |
| OPITQ | Office Properties Income Trust | 0.0130 | 0.0001 | 0.0005 | 61.8K | -0.0115 | | 95.83 | |
| OPMXF | Operadora DE Sites Mexicn | 0.8142 | 0.8142 | 0.8142 | 200 | 0.0247 | | 3.13 | |
| ORLCF | Oracle Commodity Hldg Crp | 0.0368 | 0.0345 | 0.0345 | 10.4K | 0.0023 | | 7.14 | |
| OROVY | Orient Overseas Inr U/Adr | 91.00 | 91.00 | 91.00 | 100 | -6.91 | | 7.05 | |
| OTLC | Oncotelic Therapeutcs Inc | 0.0384 | 0.0334 | 0.0368 | 165.1K | 0.0020 | | 5.75 | |
| OTMCF | Romios Gold Resources Inc | 0.4800 | 0.4800 | 0.4800 | 10.0K | -0.0150 | | 3.03 | |
| OXFYY | Oxford Nanopre Tech U/Adr | 6.900 | 6.900 | 6.900 | 200 | -0.240 | | 3.36 | |
| OZSC | Ozop Energy Solutions Inc | 0.1200 | 0.0800 | 0.1162 | 130.7K | 0.0362 | | 45.25 | |
| OZSCD | Ozop Energy Solutions New | 0.1700 | 0.1100 | 0.1248 | 28.4K | -0.0091 | | 6.80 | |