| OAP3 | Octopus Apollo Vct Plc | 46.70 | 46.70 | 46.70 | 0 | 0.00 | | 0.00 | |
| OAUE | UBS Etf | 125.6 | 125.6 | 125.6 | 333 | 0.0 | | 0.00 | |
| OBD | Oxford Biodynamics Plc | 0.2200 | 0.1800 | 0.2150 | 14.27M | 0.0200 | | 10.26 | |
| OBI | Ondine Biomedical Inc | 11.59 | 11.25 | 11.50 | 44.1K | 0.00 | | 0.00 | |
| OCDO | Ocado Group Plc | 204.9 | 190.3 | 197.0 | 7.76M | 5.6 | | 2.90 | |
| OCI | Oakley Capital Investments Limited | 501.7 | 492.0 | 496.0 | 349.8K | 4.0 | | 0.81 | |
| OCTF | First Trust Global Funds Public Limited | 2,069 | 2,069 | 2,069 | 0 | 11 | | 0.55 | |
| OE08 | Bank Of Montreal | 100.4 | 100.4 | 100.4 | 1.0M | 0.0 | | 0.00 | |
| OE61 | The Kingdom Of Morocco | 107.4 | 107.4 | 107.4 | 0 | 0.0 | | 0.00 | |
| OFG | Octopus Future Generations Vct Plc | 77.00 | 77.00 | 77.00 | 0 | 0.00 | | 0.00 | |
| OGDC | Oil and Gas Development Company Limited | 8.000 | 8.000 | 8.000 | 0 | 0.000 | | 0.00 | |
| OGG9 | Gold Bullion Securities | 373.7 | 371.9 | 371.9 | 3.5K | 2.7 | | 0.74 | |
| OGLD | Deutsche Boerse Commodities Gmbh | 131.5 | 129.0 | 129.0 | 2.4K | -2.2 | | 1.69 | |
| OGN | Origin Enterprises Plc | 397.5 | 397.5 | 397.5 | 0 | -7.5 | | 1.85 | |
| OGOL | Global X Metal Securities | 56.35 | 56.35 | 56.35 | 42 | 0.00 | | 0.00 | |
| OGZU | Wisdomtree Metal Securities Limited | 391.3 | 384.2 | 384.2 | 100 | -7.3 | | 1.85 | |
| OHGR | One Health Group Plc | 245.1 | 241.6 | 244.0 | 2.5K | -1.0 | | 0.41 | |
| OI20 | Kingdom Of Saudi Arabia (The) | 101.5 | 101.5 | 101.5 | 0 | 0.0 | | 0.00 | |
| OIG | Oryx International Growth Fund Ltd | 1,300 | 1,228 | 1,295 | 51.8K | 73 | | 5.93 | |
| OIGB | Vaneck Oil Services Ucits ETF | 24.76 | 23.97 | 24.73 | 7.3K | 0.41 | | 1.67 | |
| OIH | Orascom Investment Holding S.A.E | 0.0150 | 0.0140 | 0.0140 | 1.8K | 0.0000 | | 0.00 | |
| OIHV | Vaneck Oil Services Ucits ETF | 33.43 | 32.93 | 33.36 | 7.0K | 0.25 | | 0.76 | |
| OIL2 | Wisdomtree WTI Crude Oil 2X Daily Lev | 1,575 | 1,508 | 1,575 | 401 | 31 | | 1.97 | |
| OIL3 | UBS Etc [Cmci WTI 3M] USD | 132.1 | 132.1 | 132.1 | 0 | 0.0 | | 0.00 | |
| OILG | UBS Etc [Cmci Wti] GBP | 10,408 | 10,408 | 10,408 | 0 | 0 | | 0.00 | |
| OILU | UBS Etc [Ubs BBG CMCI WTI Crude Idx] USD | 173.5 | 173.5 | 173.5 | 0 | 1.0 | | 0.57 | |
| OIP9 | Shell International Finance B.V | 97.40 | 97.40 | 97.40 | 0 | 0.00 | | 0.00 | |
| OIT | Odyssean Investment Trust Plc | 189.0 | 186.3 | 187.0 | 610.2K | -1.3 | | 0.66 | |
| OM9S | Yorkshire Water Finance PLC | 77.40 | 77.40 | 77.40 | 0 | 0.00 | | 0.00 | |
| OMG | Oxford Metrics Plc | 51.00 | 47.10 | 51.00 | 304.3K | 1.70 | | 3.45 | |
| OMI | Orosur Mining Inc | 24.00 | 21.00 | 23.00 | 3.2M | 1.50 | | 6.98 | |
| OMIP | One Media Ip Group Plc | 3.200 | 3.100 | 3.100 | 100 | -0.100 | | 3.13 | |
| OMU | Old Mutual Limited | 62.20 | 60.51 | 61.60 | 169.6K | 0.80 | | 1.32 | |
| OMXS | Ishares Omx Stockholm Capped Ucits ETF | 840.3 | 832.2 | 839.0 | 15.4K | 6.0 | | 0.72 | |
| ONDO | Ondo Insurtech Plc | 15.00 | 14.50 | 14.75 | 267.1K | -0.25 | | 1.67 | |
| ONT | Oxford Nanopore Technologies Plc | 120.9 | 115.4 | 120.0 | 1.48M | 3.8 | | 3.27 | |
| ONWD | Onward Opportunities Limited | 129.0 | 126.0 | 126.0 | 32.2K | 0.0 | | 0.00 | |
| OOA | Octopus Aim Vct Plc | 38.60 | 37.60 | 37.60 | 7.7K | 0.40 | | 1.08 | |
| OPEN | Ish Re Incl / Diversity ETF | 10.61 | 10.58 | 10.58 | 10.6K | 0.02 | | 0.15 | |
| OPT | Optima Health Plc | 182.0 | 178.0 | 180.0 | 63.7K | 0.0 | | 0.00 | |
| OPTI | Optibiotix Health Plc | 5.400 | 5.200 | 5.300 | 619.7K | 0.000 | | 0.00 | |
| OQ12 | Standard Chartered PLC | 91.02 | 91.02 | 91.02 | 0 | 0.00 | | 0.00 | |
| ORC1 | Orchard Bond Finance PLC | 100.0 | 100.0 | 100.8 | 0 | 2.2 | | 2.21 | |
| ORCA | Orcadian Energy Plc | 18.00 | 15.00 | 17.00 | 90.9K | 1.00 | | 6.25 | |
| ORCH | Orchard Funding Group Plc | 59.00 | 56.00 | 57.50 | 16.7K | 0.00 | | 0.00 | |
| ORCP | Oracle Power Plc | 0.0650 | 0.0550 | 0.0640 | 434.83M | 0.0010 | | 1.59 | |
| ORIT | Octopus Renewables Infrastructure Trust | 61.70 | 59.70 | 60.70 | 2.8M | 1.00 | | 1.68 | |
| ORNT | Orient Telecoms Plc | 4.000 | 4.000 | 4.000 | 0 | 0.000 | | 0.00 | |
| ORR | Oriole Resources Plc | 0.3600 | 0.3200 | 0.3450 | 76.03M | 0.0150 | | 4.55 | |
| OS73 | Toyota Finance Australia Limited | 95.17 | 95.17 | 95.17 | 0 | 0.00 | | 0.00 | |
| OSB | Osb Group Plc | 564.5 | 553.5 | 554.5 | 381.3K | 0.5 | | 0.09 | |
| OSEC | Octopus Aim Vct 2 Plc | 30.00 | 30.00 | 30.00 | 0 | 0.40 | | 1.35 | |
| OSX5 | Source Markets Public Limited Company | 57.44 | 57.14 | 57.44 | 0 | 0.00 | | 0.00 | |
| OT06 | Derwent London PLC | 72.10 | 72.10 | 72.10 | 9.6K | 0.00 | | 0.00 | |
| OT1 | Oxford Technology 2 Venture Capital | 14.50 | 14.50 | 14.50 | 0 | 0.00 | | 0.00 | |
| OT3 | Oxford Technology 2 Venture Capital | 7.500 | 7.500 | 7.500 | 0 | 0.000 | | 0.00 | |
| OT4 | Oxford Technology 2 Venture Capital | 7.500 | 7.500 | 7.500 | 0 | 0.000 | | 0.00 | |
| OTB | On The Beach Group Plc | 181.6 | 172.6 | 176.0 | 664.8K | 0.2 | | 0.11 | |
| OTES | Hellenic Telecommunications Organization | 10.85 | 10.20 | 10.72 | 2 | 0.00 | | 0.00 | |
| OTPD | Gdr [Each Repr 1/2 Ord Huf100][Reg S] | 17.00 | 17.00 | 17.00 | 0 | 0.00 | | 0.00 | |
| OTV2 | Octopus Titan Vct Plc | 22.00 | 20.50 | 20.50 | 50.0K | 0.00 | | 0.00 | |
| OVCT | Oberon Aim Vct Plc | 23.50 | 20.00 | 23.50 | 1.0K | 0.00 | | 0.00 | |
| OVZA | Wisdomtree Metal Securities Limited | 166.3 | 161.0 | 162.1 | 100 | 3.8 | | 2.43 | |
| OVZB | Wisdomtree Metal Securities Limited | 123.3 | 120.7 | 120.9 | 0 | -0.3 | | 0.26 | |
| OVZC | Wisdomtree Metal Securities Limited | 62.00 | 60.26 | 60.26 | 925 | 1.92 | | 3.29 | |
| OXA1 | Physical Gold Euro Hdg Etc | 273.6 | 273.4 | 273.6 | 738 | 2.4 | | 0.88 | |
| OXA2 | Physical Silver Euro Hdg Etc | 415.3 | 415.3 | 415.3 | 100 | 7.9 | | 1.93 | |
| OXA5 | Physical Gold Etc 27/08/60 | 392.3 | 390.2 | 390.2 | 100 | -2.2 | | 0.55 | |
| OXA6 | Physical Silver Etc 27/08/60 | 568.7 | 568.7 | 568.7 | 100 | -36.5 | | 6.02 | |
| OXB | Oxford Biomedica Plc | 626.0 | 600.0 | 620.0 | 140.2K | -1.0 | | 0.16 | |
| OXH | Oxford Technology 2 Venture Capital | 7.000 | 7.000 | 7.000 | 0 | 0.000 | | 0.00 | |
| OXIG | Oxford Instruments Plc | 2,832 | 2,728 | 2,812 | 118.1K | 68 | | 2.48 | |
| OZ76 | Nationwide Building Society | 98.25 | 98.25 | 98.25 | 578.0K | 0.00 | | 0.00 | |