| OAP3 | Octopus Apollo Vct PLC | 45.20 | 45.20 | 46.70 | 1.1K | -1.50 | | 3.21 | |
| OAUE | UBS Etf | 125.6 | 125.6 | 125.6 | 333 | 0.0 | | 0.00 | |
| OBD | Oxford Biodynamics PLC | 0.2100 | 0.1800 | 0.2000 | 5.44M | 0.0050 | | 2.63 | |
| OBI | Ondine Biomedical Inc. | 11.45 | 10.75 | 11.00 | 378.1K | 0.50 | | 4.76 | |
| OCDO | Ocado Group PLC | 205.0 | 191.7 | 194.2 | 4.84M | 5.7 | | 3.10 | |
| OCI | Oakley Capital Investments Limited | 502.0 | 484.8 | 494.0 | 729.0K | 14.0 | | 2.95 | |
| OCTF | First Trust Global Funds Public Limited | 2,014 | 2,014 | 2,032 | 150 | -8 | | 0.40 | |
| OE08 | Bank Of Montreal | 100.4 | 100.4 | 100.4 | 1.0M | 0.0 | | 0.00 | |
| OE61 | The Kingdom Of Morocco | 105.7 | 105.7 | 105.7 | 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 | 8.200 | 8.200 | 8.200 | 120 | 0.000 | | 0.00 | |
| OGG9 | Gold Bullion Securities LD | 376.9 | 376.9 | 376.9 | 0 | -31.4 | | 8.58 | |
| OGLD | Deutsche Boerse Commodities Gmbh | 131.9 | 131.8 | 131.9 | 1.1K | -11.4 | | 8.81 | |
| OGN | Origin Enterprises PLC | 400.0 | 398.1 | 412.5 | 3.2K | -394.9 | | 104.60 | |
| OGOL | Global X Metal Securities | 56.35 | 56.35 | 56.35 | 16 | 5.12 | | 9.09 | |
| OGZU | Wisdomtree Metal Securities Limited | 394.0 | 390.9 | 391.0 | 14 | -33.8 | | 8.73 | |
| OHGR | One Health Group PLC | 249.5 | 240.0 | 246.0 | 8.8K | 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 | 1,194 | 1,230 | 31.9K | 30 | | 2.50 | |
| OIGB | Vaneck Ucits Etfs PLC | 24.85 | 23.33 | 24.76 | 41.2K | -0.25 | | 0.98 | |
| OIH | Orascom Investment Holding S.A.E | 0.0150 | 0.0140 | 0.0140 | 1.8K | 0.0000 | | 0.00 | |
| OIHV | Vaneck Ucits Etfs PLC | 33.32 | 32.14 | 33.27 | 131.5K | 0.12 | | 0.36 | |
| OIL2 | Wisdomtree Commodity Securities Limited | 1,473 | 1,328 | 1,461 | 13.1K | 184 | | 10.37 | |
| OIL3 | UBS AG | 112.2 | 109.7 | 132.1 | 128 | 0.0 | | 0.00 | |
| OILG | UBS AG | 7,466 | 7,466 | 10,408 | 0 | 0 | | 0.00 | |
| OILU | UBS AG | 161.2 | 161.2 | 164.9 | 102 | 9.0 | | 5.49 | |
| OIP9 | Shell International Finance B.V | 97.08 | 97.08 | 97.08 | 0 | 0.00 | | 0.00 | |
| OIT | Odyssean Investment Trust PLC | 185.0 | 173.6 | 181.0 | 405.0K | 6.5 | | 3.74 | |
| OM9S | Yorkshire Water Finance PLC | 77.40 | 77.40 | 77.40 | 0 | 0.00 | | 0.00 | |
| OMG | Oxford Metrics PLC | 47.00 | 44.20 | 46.70 | 313.7K | 1.60 | | 3.61 | |
| OMI | Orosur Mining INC | 20.50 | 17.60 | 19.50 | 3.84M | 1.25 | | 6.76 | |
| OMIP | One Media Ip Group PLC | 3.200 | 3.000 | 3.100 | 8.4K | 0.000 | | 0.00 | |
| OMU | Old Mutual Limited | 68.40 | 63.60 | 66.40 | 352.4K | 3.60 | | 5.59 | |
| OMXS | Ishares Iv PLC | 825.8 | 816.0 | 819.5 | 13.8K | 40.9 | | 5.18 | |
| ONDO | Ondo Insurtech PLC | 14.50 | 14.25 | 14.50 | 235.5K | 0.40 | | 2.76 | |
| ONT | Oxford Nanopore Technologies PLC | 122.8 | 114.5 | 114.5 | 2.06M | -0.7 | | 0.58 | |
| ONWD | Onward Opportunities Limited | 124.6 | 121.8 | 123.0 | 40.9K | 1.0 | | 0.82 | |
| OOA | Octopus Aim Vct PLC | 38.60 | 38.60 | 37.20 | 2.3K | 0.00 | | 0.00 | |
| OPEN | Ishares Iv PLC | 10.41 | 10.41 | 10.32 | 2 | 0.40 | | 4.00 | |
| OPT | Optima Health PLC | 183.0 | 180.0 | 180.5 | 53.7K | 0.0 | | 0.00 | |
| OPTI | Optibiotix Health PLC | 5.500 | 5.000 | 5.250 | 232.7K | 0.050 | | 0.96 | |
| OQ12 | Standard Chartered PLC | 91.00 | 91.00 | 91.00 | 0 | 0.00 | | 0.00 | |
| ORC1 | Orchard Bond Finance PLC | 100.1 | 100.0 | 100.8 | 0 | 2.2 | | 2.21 | |
| ORCA | Orcadian Energy PLC | 15.00 | 13.40 | 14.00 | 60.3K | -0.50 | | 3.57 | |
| ORCH | Orchard Funding Group PLC | 56.88 | 54.56 | 56.00 | 80.2K | 1.50 | | 2.75 | |
| ORCP | Oracle Power PLC | 0.0480 | 0.0400 | 0.0440 | 77.27M | 0.0000 | | 0.00 | |
| ORIT | Octopus Renewables Infrastructure Trust | 57.80 | 54.10 | 57.40 | 1.4M | 1.40 | | 2.64 | |
| ORNT | Orient Telecoms PLC | 3.200 | 3.200 | 4.000 | 5.0K | 0.000 | | 0.00 | |
| ORR | Oriole Resources PLC | 0.2960 | 0.2700 | 0.2850 | 13.06M | 0.0050 | | 1.82 | |
| OS73 | Toyota Finance Australia Limited | 95.17 | 95.17 | 95.17 | 0 | 0.00 | | 0.00 | |
| OSB | Osb Group PLC | 550.5 | 536.0 | 542.5 | 1.61M | 22.5 | | 4.39 | |
| OSEC | Octopus Aim Vct 2 PLC | 30.60 | 30.60 | 29.60 | 1.1K | 0.00 | | 0.00 | |
| OSX5 | Source Markets Public Limited Company | 57.56 | 57.56 | 57.56 | 0 | 2.00 | | 3.75 | |
| OT06 | Derwent London PLC | 72.10 | 72.10 | 72.10 | 9.6K | 0.00 | | 0.00 | |
| OT1 | Oxford Technology 2 Venture Capital | 12.00 | 12.00 | 14.50 | 2.5K | 0.00 | | 0.00 | |
| OT3 | Oxford Technology 2 Venture Capital | 5.500 | 5.500 | 7.500 | 33.0K | 0.000 | | 0.00 | |
| OT4 | Oxford Technology 2 Venture Capital | 8.500 | 8.500 | 7.500 | 10.0K | 0.000 | | 0.00 | |
| OTB | On The Beach Group PLC | 180.0 | 171.2 | 173.4 | 1.08M | 11.6 | | 7.05 | |
| OTES | Hellenic Telecommunications Organization | 10.45 | 10.45 | 10.45 | 0 | 0.00 | | 0.00 | |
| OTPD | Otp Bank PLC | 17.00 | 17.00 | 17.00 | 1 | 0.00 | | 0.00 | |
| OTV2 | Octopus Titan Vct PLC | 22.00 | 22.00 | 20.50 | 447 | 0.00 | | 0.00 | |
| OVCT | Oberon Aim Vct PLC | 20.00 | 20.00 | 23.50 | 1.0K | 0.00 | | 0.00 | |
| OVZA | Wisdomtree Metal Securities Limited | 162.7 | 158.4 | 159.6 | 54 | -7.1 | | 4.52 | |
| OVZB | Wisdomtree Metal Securities Limited | 125.3 | 119.1 | 123.5 | 37 | -5.8 | | 4.87 | |
| OVZC | Wisdomtree Metal Securities Limited | 60.26 | 58.10 | 58.66 | 7.1K | -2.42 | | 4.24 | |
| OXA1 | Db Etc PLC | 273.4 | 272.3 | 272.8 | 1.1K | 8.2 | | 3.13 | |
| OXA2 | Db Etc PLC | 378.6 | 378.6 | 378.6 | 21 | -11.5 | | 2.95 | |
| OXA5 | Db Etc PLC | 393.4 | 392.9 | 392.9 | 76 | -28.2 | | 7.18 | |
| OXA6 | Db Etc PLC | 562.0 | 545.4 | 547.9 | 62 | 0.6 | | 0.10 | |
| OXB | Oxford Biomedica PLC | 589.0 | 550.0 | 574.0 | 213.3K | 24.0 | | 4.29 | |
| OXH | Oxford Technology 2 Venture Capital | 8.000 | 8.000 | 7.000 | 20.0K | 0.000 | | 0.00 | |
| OXIG | Oxford Instruments PLC | 2,626 | 2,522 | 2,592 | 192.2K | 126 | | 5.04 | |
| OZ76 | Nationwide Building Society | 98.25 | 98.25 | 98.25 | 578.0K | 0.00 | | 0.00 | |