| OFSSO | OFS Capital Corporation - 7.50% Notes due 2028 | | |
| OGGWZ | Osisko Gold Group Inc. - Warrant | | |
| OGI | Organigram Global Inc. - Common Shares | | |
| OHAC | Oceanhawk Acquisition Corp. - Class A Ordinary Shares | | |
| OHACR | Oceanhawk Acquisition Corp. - Rights | | |
| OHACU | Oceanhawk Acquisition Corp. - Units | | |
| OIG | Orion180 Insurance Group Inc. - Class A Common Stock | | |
| OIM | OneIM Acquisition Corp. - Class A Ordinary Shares | | |
| OIMAU | OneIM Acquisition Corp. - Units | | |
| OIMAW | OneIM Acquisition Corp. - Warrant | | |
| OIO | OIO Group - Ordinary Shares | | |
| OIOWW | OIO Group - Warrants | | |
| OKTA | Okta, Inc. - Class A Common Stock | | |
| OKUR | OnKure Therapeutics, Inc. - Class A Common Stock | | |
| OKYO | OKYO Pharma Limited - Ordinary Shares | | |
| OLB | The OLB Group, Inc. - Common Stock | D | |
| OLED | Universal Display Corporation - Common Stock | | |
| OLLI | Ollie's Bargain Outlet Holdings, Inc. - Common Stock | | |
| OLMA | Olema Pharmaceuticals, Inc. - Common Stock | | |
| OLOX | Olenox Industries Inc. - Common Stock | | |
| OM | Outset Medical, Inc. - Common Stock | | |
| OMAB | Grupo Aeroportuario del Centro Norte S.A.B. de C.V. - American Depositary Shares each representing 8 Series B shares | | |
| OMCL | Omnicell, Inc. - Common Stock | | |
| OMDA | Omada Health, Inc. - Common Stock | | |
| OMER | Omeros Corporation - Common Stock | | |
| OMEX | Odyssey Marine Exploration, Inc. - Common Stock | D | |
| OMH | Ohmyhome Limited - Class A Ordinary Shares | | |
| OMSE | OMS Energy Technologies Inc. - Ordinary Shares | | |
| ON | ON Semiconductor Corporation - Common Stock | | SP500 |
| ONB | Old National Bancorp - Common Stock | | |
| ONBPO | Old National Bancorp - Depositary Shares, Each Representing a 1/40th Interest in a Share of Series C Preferred Stock | | |
| ONBPP | Old National Bancorp - Depositary Shares, Each Representing a 1/40th Interest in a Share of Series A Preferred Stock | | |
| ONC | BeOne Medicines Ltd. - American Depositary Shares | | |
| ONCH | 1RT Acquisition Corp. - Class A Ordinary Share | | |
| ONCHU | 1RT Acquisition Corp. - Units | | |
| ONCHW | 1RT Acquisition Corp. - Warrant | | |
| ONCO | Onconetix, Inc. - Common Stock | | |
| ONCY | Oncolytics Biotech Inc. - Common Stock | D | |
| ONDS | Ondas Inc - Common Stock | | |
| ONEG | OneConstruction Group Limited - Ordinary Shares | | |
| ONEN | ONE Nuclear Energy Inc. - Common Stock | | |
| ONEW | OneWater Marine Inc. - Class A Common Stock | | |
| ONFO | Onfolio Holdings Inc. - Common Stock | D | |
| ONFOW | Onfolio Holdings Inc. - Warrant | D | |
| ONMD | OneMedNet Corp - Class A Common Stock | | |
| ONMDW | OneMedNet Corp - Warrant | | |
| OPAD | Offerpad Solutions Inc. - Class A Common Stock | | |
| OPAL | OPAL Fuels Inc. - Class A Common Stock | | |
| OPBK | OP Bancorp - Common Stock | | |
| OPCH | Option Care Health, Inc. - Common Stock | | |