- ONIT — Onity Group Inc.
- ONL — Orion Properties Inc.
- ONLN — ProShares - Online Retail ETF
- ONMBF — Onamba Co., Ltd.
- ONMD — OneMedNet Corporation
- ONMDW — OneMedNet Corporation
- ONOF — Global X - Adaptive U.S. Risk Management ETF
- ONON — On Holding AG
- ONPH — Oncology Pharma Inc.
- ONT — Onterris, Inc.
- ONTO — Onto Innovation Inc.
- ONTTF — Oxford Nanopore Technologies plc
- ONVC — Online Vacation Center Holdings Corp.
- ONVVF — Oneview Healthcare PLC
- ONXXF — Ontex Group N.V.
- ONXYY — Ontex Group N.V.
- OOAG — OMDA Oil and Gas, Inc.
- OOBHF — On the Beach Group plc
- OODH — Orion Diversified Holding Co. Inc.
- OOGI — C2E Energy, Inc.
- OOMA — Ooma, Inc.
- OONEF — 01 Quantum Inc.
- OOO.AX — BetaShares Crude Oil Index ETF-Currency Hedged (Synthetic)
- OOSP — Obra Opportunistic Structured Products ETF
- OPAD — Offerpad Solutions Inc.
- OPAL — OPAL Fuels Inc.
- OPBK — OP Bancorp
- OPCH — Option Care Health, Inc.
- OPEG — Leverage Shares 2x Long OPEN Daily ETF
- OPEN — Opendoor Technologies Inc.
- OPER — ClearShares Ultra-Short Maturity ETF
- OPESF — Otello Corporation ASA
- OPFI — OppFi Inc.
- OPHC — OptimumBank Holdings, Inc.
- OPHLF — Ono Pharmaceutical Co., Ltd.
- OPHLY — Ono Pharmaceutical Co., Ltd.
- OPHR.V — Ophir Gold Corp.
- OPI — Office Properties Income Trust
- OPK — OPKO Health, Inc.
- OPLN — OPENLANE Inc. Common Stock
- OPMG — Options Media Group Holdings, Inc.
- OPMXF — Operadora de Sites Mexicanos, S.A.B. de C.V.
- OPMZ — 1PM Industries, Inc.
- OPNDF — OpenDoor Inc.
- OPORF — hVIVO plc
- OPPE — WisdomTree European Opportunities Fund
- OPPG — WisdomTree GeoAlpha Opportunities Fund
- OPPJ — WisdomTree Japan Opportunities Fund
- OPPS.NE — MANULIFE ALTERNATIVE OPPORTUNITIES FUND
- OPRA — Opera Limited
- OPRT — Oportun Financial Corporation
- OPRX — OptimizeRx Corporation
- OPST — OPT-Sciences Corporation
- OPTH — Optimi Health Corp.
- OPTI — Optec International, Inc.
- OPTI.CN — Optimi Health Corp.
- OPTL — Optimum Interactive USA Ltd.
- OPTT — Ocean Power Technologies, Inc.
- OPTU — Optimum Communications, Inc.
- OPTX — Syntec Optics Holdings, Inc.
- OPTXW — Syntec Optics Holdings, Inc.
- OPTZ — Optimize Strategy Index ETF
- OPUS — Opus Magnum Ameris, Inc.
- OPVS — NanoFlex Power Corporation
- OPW.V — Opawica Explorations Inc.
- OPWEF — Opawica Explorations Inc.
- OPXS — Optex Systems Holdings, Inc
- OPY — Oppenheimer Holdings Inc.
- OQLGF — Olympique Lyonnais Groupe S.A.
- OR — OR Royalties Inc.
- OR.TO — OR Royalties Inc.
- OR3.AX — Ore Resources Limited
- ORA — Ormat Technologies, Inc.
- ORA.AX — Orora Limited
- ORAGF — Monarca Minerals Inc.
- ORANY — Orange S.A.
- ORBN — Oregon Bancorp, Inc.
- ORBS — Eightco Holdings Inc.
- ORBT — Orbit International Corp.
- ORBX — Global X Space Tech ETF
- ORC — Orchid Island Capital, Inc.
- ORC-B.V — Orca Energy Group Inc.
- ORCL — Oracle Corporation
- ORCS — Direxion Daily ORCL Bear 1X ETF
- ORCU — Direxion Daily ORCL Bull 2X ETF
- ORCX — Daily Target 2X Long ORCL ETF
- ORD.AX — Ordell Minerals Limited
- ORE.AX — Orezone Gold Corporation
- ORE.TO — Orezone Gold Corporation
- OREAF — Orea Mining Corp.
- ORENF — Origin Enterprises plc
- ORESF — Orestone Mining Corp.
- ORFDF — Orecap Invest Corp.
- ORG.AX — Origin Energy Limited
- ORGH — OrgHarvest, Inc.
- ORGJF — Organo Corporation
- ORGN.CN — Origen Resources Inc.
- ORGO — Organogenesis Holdings Inc.
- ORGS — Orgenesis Inc.
- ORHB — ORHub, Inc.
