- ORCU — Direxion Daily ORCL Bull 2X ETF
- ORCX — Daily Target 2X Long ORCL ETF
- ORE.TO — Orezone Gold Corporation
- OREA.TO — Orea Mining Corp.
- ORECX — Invesco Oppenheimer Real Estate Fund Class C
- ORENX — Invesco Oppenheimer Real Estate Fund Class R
- OREX — Orexigen Therapeutics, Inc.
- ORFN — Constrained Capital ESG Orphans ETF
- ORG — The Organics ETF
- ORGN — Origin Materials, Inc.
- ORGNW — Origin Materials, Inc.
- ORGO — Organogenesis Holdings Inc.
- ORI — Old Republic International Corporation
- ORIA — Orion Biotech Opportunities Corp.
- ORIAU — Orion Biotech Opportunities Corp.
- ORIAW — Orion Biotech Opportunities Corp.
- ORIC — ORIC Pharmaceuticals, Inc.
- ORIG — Ocean Rig UDW Inc.
- ORIO — Orion Digital Corp. Common Shares
- ORIO.TO — Orion Digital Corp.
- ORIQ — Origin Investment Corp I Ordinary Shares
- ORIQU — Origin Investment Corp I Units
- ORIQW — Origin Investment Corp I Warrant.
- ORIS — ORIENTAL RISE HOLDINGS Ltd
- ORKA — Oruka Therapeutics, Inc.
- ORKT — Orangekloud Technology Inc.
- ORL.TO — Allkem Limited
- ORLA — Orla Mining Ltd.
- ORLG — Leverage Shares 2x Long ORLY Daily ETF
- ORLY — O'Reilly Automotive, Inc.
- ORM.V — Orford Mining Corporation
- ORMP — Oramed Pharmaceuticals Inc.
- ORN — Orion Group Holdings, Inc.
- ORPH — Orphazyme A/S
- ORR — Militia Long/Short Equity ETF
- ORRF — Orrstown Financial Services, Inc.
- ORS.V — Orestone Mining Corp.
- ORSTX — Invesco Short Term Municipal A
- ORTX — Orchard Therapeutics plc
- ORV.TO — Orvana Minerals Corp.
- ORX.V — Orefinders Resources Inc.
- OS — OneStream, Inc. Class A Common Stock
- OSA — ProSomnus, Inc.
- OSAAW — ProSomnus, Inc.
- OSBC — Old Second Bancorp, Inc.
- OSCG — Leverage Shares 2x Long OSCR Daily ETF
- OSCR — Oscar Health, Inc.
- OSCX — Defiance Daily Target 2X Long OSCR ETF
- OSEA — Harbor International Compounders ETF (OSEA)
- OSG — Octave Specialty Group, Inc.
- OSGIX — JPMorgan Mid Cap Growth A
- OSH — Oak Street Health, Inc.
- OSI — Osiris Acquisition Corp.
- OSI-UN — Osiris Acquisition Corp.
- OSI.V — Osino Resources Corp.
- OSIS — OSI Systems, Inc.
- OSK — Oshkosh Corporation
- OSK.TO — Osisko Mining Inc.
- OSLE — Oaktree Specialty Lending Corpo
- OSMT — RVL Pharmaceuticals plc
- OSN — Ossen Innovation Co., Ltd.
- OSP.TO — Brompton Oil Split Corp.
- OSPN — OneSpan Inc.
- OSPRU — Osprey Acquisition Corp. III
- OSRH — OSR Holdings, Inc.
- OSRHW — OSR Holdings, Inc.
- OSS — One Stop Systems, Inc.
- OSS.V — OneSoft Solutions Inc.
- OST — Ostin Technology Group Co., Ltd.
- OSTK — Overstock.com, Inc.
- OSTR — Oyster Enterprises Acquisition Corp.
- OSTRU — Oyster Enterprises Acquisition Corp.
- OSTRW — Oyster Enterprises Acquisition Corp.
- OSTX — OS Therapies Incorporated
- OSUR — OraSure Technologies, Inc.
- OSW — OneSpaWorld Holdings Limited
- OTAI — Starlink Ai Acquisition Corp.
- OTC.V — Ocumetics Technology Corp.
- OTCFX — T. Rowe Price Small-Cap Stock Fund
- OTCIX — MFS Mid Cap Growth I
- OTCKX — MFS Mid Cap Growth Fund Class R6
- OTCNX — Invesco Discovery Large Cap R
- OTCRX — Otter Creek Long/Short Opportunity Fund - Investor Class
- OTEC — OceanTech Acquisitions I Corp.
- OTECU — OceanTech Acquisitions I Corp.
- OTECW — OceanTech Acquisitions I Corp.
- OTEX — Open Text Corporation
- OTEX.TO — Open Text Corporation
- OTF — Blue Owl Technology Finance Corp.
- OTGA — OTG Acquisition Corp. I Class A Ordinary Share
- OTGAU — OTG Acquisition Corp. I Unit
- OTGAW — OTG Acquisition Corp. I Warrants
- OTGL — OTG Latin America ETF
- OTH — Off The Hook YS Inc.
- OTIC — Otonomy, Inc.
- OTIIX — T. Rowe Price Small-Cap Stock Fund
- OTIS — Otis Worldwide Corporation
- OTLK — Outlook Therapeutics, Inc.
- OTLKW — Outlook Therapeutics, Inc. - Se
- OTLY — Oatly Group AB
